diff --git a/.github/workflows/runtime-tests.yml b/.github/workflows/runtime-tests.yml
index d189f0c1728..56f0cf895f4 100644
--- a/.github/workflows/runtime-tests.yml
+++ b/.github/workflows/runtime-tests.yml
@@ -6,6 +6,9 @@ on:
     branches: [ master, main-* ]
   merge_group:
 
+env:
+  dotnet-version: 6.0.x # SDK Version for building Dafny
+  
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}
   cancel-in-progress: true
@@ -25,6 +28,10 @@ jobs:
         uses: actions/checkout@v4
         with:
           submodules: true
+      - name: Setup dotnet
+        uses: actions/setup-dotnet@v4
+        with:
+          dotnet-version: ${{env.dotnet-version}}
       - name: Set up JDK 18
         uses: actions/setup-java@v4
         with:
diff --git a/Source/DafnyCore.Test/ClonerTest.cs b/Source/DafnyCore.Test/ClonerTest.cs
index 67d6023266e..dcf80afe369 100644
--- a/Source/DafnyCore.Test/ClonerTest.cs
+++ b/Source/DafnyCore.Test/ClonerTest.cs
@@ -27,11 +27,11 @@ public void ClonerKeepsBodyStartTok() {
     var rangeToken = new RangeToken(Token.NoToken, Token.NoToken);
     var specificationFrame = new LiteralExpr(Microsoft.Dafny.Token.NoToken, 1);
     var formal1 = new Formal(Token.NoToken, "a", Microsoft.Dafny.Type.Bool, true, false, null) {
-      RangeToken = new RangeToken(tokenBodyStart, tokenBodyStart),
+      RangeOrigin = new RangeToken(tokenBodyStart, tokenBodyStart),
       IsTypeExplicit = true
     };
     var formal2 = new Formal(Token.NoToken, "b", Microsoft.Dafny.Type.Bool, true, false, null) {
-      RangeToken = new RangeToken(tokenBodyStart, tokenBodyStart),
+      RangeOrigin = new RangeToken(tokenBodyStart, tokenBodyStart),
       IsTypeExplicit = false
     };
     var dummyDecl = new Method(rangeToken, new Name(rangeToken, "hello"),
@@ -45,9 +45,9 @@ public void ClonerKeepsBodyStartTok() {
     var cloner = new Cloner();
     var dummyDecl2 = cloner.CloneMethod(dummyDecl);
     Assert.Equal(2, dummyDecl2.BodyStartTok.line);
-    Assert.Equal(2, dummyDecl2.Ins[0].RangeToken.StartToken.line);
+    Assert.Equal(2, dummyDecl2.Ins[0].Origin.StartToken.line);
     Assert.True(dummyDecl2.Ins[0].IsTypeExplicit);
-    Assert.Equal(2, dummyDecl2.Ins[1].RangeToken.StartToken.line);
+    Assert.Equal(2, dummyDecl2.Ins[1].Origin.StartToken.line);
     Assert.False(dummyDecl2.Ins[1].IsTypeExplicit);
   }
 }
\ No newline at end of file
diff --git a/Source/DafnyCore.Test/NodeTests.cs b/Source/DafnyCore.Test/NodeTests.cs
index a5cab96ec0c..842833b02ee 100644
--- a/Source/DafnyCore.Test/NodeTests.cs
+++ b/Source/DafnyCore.Test/NodeTests.cs
@@ -6,13 +6,20 @@ namespace DafnyCore.Test;
 public class NodeTests {
 
   class ConcreteNode : Node {
-    public ConcreteNode(RangeToken rangeOrigin, IEnumerable<INode>? children = null) {
-      RangeToken = rangeOrigin;
+    private IOrigin origin;
+
+    public ConcreteNode(IOrigin rangeToken, IEnumerable<INode>? children = null) {
+      origin = rangeToken;
       Children = children ?? Enumerable.Empty<INode>();
     }
 
-    public override RangeToken RangeToken { get; set; }
-    public override IOrigin Tok => RangeToken.StartToken;
+    public override IOrigin Origin => origin;
+
+    public override IOrigin RangeOrigin {
+      set => origin = value;
+    }
+
+    public override IOrigin Tok => origin.StartToken;
     public override IEnumerable<INode> Children { get; }
     public override IEnumerable<INode> PreResolveChildren => Children;
   }
diff --git a/Source/DafnyCore/AST/Attributes.cs b/Source/DafnyCore/AST/Attributes.cs
index 89be3e915b6..f493e074b82 100644
--- a/Source/DafnyCore/AST/Attributes.cs
+++ b/Source/DafnyCore/AST/Attributes.cs
@@ -306,7 +306,7 @@ public static Attributes ExpandAtAttribute(Program program, UserSuppliedAtAttrib
     var bindings = atAttribute.UserSuppliedPreResolveBindings;
 
     if (name == null) {
-      program.Reporter.Error(MessageSource.Resolver, atAttribute.RangeToken, "Attribute not recognized: " + atAttribute.ToString());
+      program.Reporter.Error(MessageSource.Resolver, atAttribute.Origin, "Attribute not recognized: " + atAttribute.ToString());
       return null;
     }
 
@@ -316,7 +316,7 @@ public static Attributes ExpandAtAttribute(Program program, UserSuppliedAtAttrib
     }
 
     if (!builtinSyntax.CanBeApplied(attributeHost)) {
-      program.Reporter.Error(MessageSource.Resolver, atAttribute.RangeToken, UserSuppliedAtAttribute.AtName + atAttribute.UserSuppliedName + " attribute cannot be applied to " + attributeHost.WhatKind);
+      program.Reporter.Error(MessageSource.Resolver, atAttribute.Origin, UserSuppliedAtAttribute.AtName + atAttribute.UserSuppliedName + " attribute cannot be applied to " + attributeHost.WhatKind);
     }
 
     var resolver = new ModuleResolver(new ProgramResolver(program), program.Options) {
@@ -614,7 +614,7 @@ private static void ResolveLikeDatatypeConstructor(Program program, Formal[] for
     // Verify that provided arguments are given literally
     foreach (var binding in bindings.ArgumentBindings) {
       if (binding.Actual is not LiteralExpr) {
-        program.Reporter.Error(MessageSource.Resolver, binding.Actual.RangeToken, $"Argument to attribute {attrName} must be a literal");
+        program.Reporter.Error(MessageSource.Resolver, binding.Actual.Origin, $"Argument to attribute {attrName} must be a literal");
       }
     }
   }
diff --git a/Source/DafnyCore/AST/Cloner.cs b/Source/DafnyCore/AST/Cloner.cs
index 8ce07333688..fddec9b207b 100644
--- a/Source/DafnyCore/AST/Cloner.cs
+++ b/Source/DafnyCore/AST/Cloner.cs
@@ -66,7 +66,7 @@ public virtual TopLevelDecl CloneDeclaration(TopLevelDecl d, ModuleDefinition ne
 
       if (d is AbstractTypeDecl) {
         var dd = (AbstractTypeDecl)d;
-        return new AbstractTypeDecl(Range(dd.RangeToken), dd.NameNode.Clone(this), newParent,
+        return new AbstractTypeDecl(Origin(dd.Origin), dd.NameNode.Clone(this), newParent,
           CloneTPChar(dd.Characteristics), dd.TypeArgs.ConvertAll(CloneTypeParam),
           dd.ParentTraits.ConvertAll(CloneType),
           dd.Members.ConvertAll(d => CloneMember(d, false)), CloneAttributes(dd.Attributes), dd.IsRefining);
@@ -75,23 +75,23 @@ public virtual TopLevelDecl CloneDeclaration(TopLevelDecl d, ModuleDefinition ne
           !(d is NonNullTypeDecl)); // don't clone the non-null type declaration; close the class, which will create a new non-null type declaration
         var dd = (SubsetTypeDecl)d;
         var tps = dd.TypeArgs.ConvertAll(CloneTypeParam);
-        return new SubsetTypeDecl(Range(dd.RangeToken), dd.NameNode.Clone(this), CloneTPChar(dd.Characteristics), tps,
+        return new SubsetTypeDecl(Origin(dd.Origin), dd.NameNode.Clone(this), CloneTPChar(dd.Characteristics), tps,
           newParent, CloneBoundVar(dd.Var, false), CloneExpr(dd.Constraint), dd.WitnessKind, CloneExpr(dd.Witness),
           CloneAttributes(dd.Attributes));
       } else if (d is TypeSynonymDecl) {
         var dd = (TypeSynonymDecl)d;
         var tps = dd.TypeArgs.ConvertAll(CloneTypeParam);
-        return new TypeSynonymDecl(Range(dd.RangeToken), dd.NameNode.Clone(this), CloneTPChar(dd.Characteristics), tps,
+        return new TypeSynonymDecl(Origin(dd.Origin), dd.NameNode.Clone(this), CloneTPChar(dd.Characteristics), tps,
           newParent, CloneType(dd.Rhs), CloneAttributes(dd.Attributes));
       } else if (d is NewtypeDecl) {
         var dd = (NewtypeDecl)d;
         if (dd.Var == null) {
-          return new NewtypeDecl(Range(dd.RangeToken), dd.NameNode.Clone(this), dd.TypeArgs.ConvertAll(CloneTypeParam), newParent,
+          return new NewtypeDecl(Origin(dd.Origin), dd.NameNode.Clone(this), dd.TypeArgs.ConvertAll(CloneTypeParam), newParent,
             CloneType(dd.BaseType), dd.WitnessKind, CloneExpr(dd.Witness),
             dd.ParentTraits.ConvertAll(CloneType),
             dd.Members.ConvertAll(d => CloneMember(d, false)), CloneAttributes(dd.Attributes), dd.IsRefining);
         } else {
-          return new NewtypeDecl(Range(dd.RangeToken), dd.NameNode.Clone(this), dd.TypeArgs.ConvertAll(CloneTypeParam), newParent,
+          return new NewtypeDecl(Origin(dd.Origin), dd.NameNode.Clone(this), dd.TypeArgs.ConvertAll(CloneTypeParam), newParent,
             CloneBoundVar(dd.Var, false), CloneExpr(dd.Constraint), dd.WitnessKind, CloneExpr(dd.Witness),
             dd.ParentTraits.ConvertAll(CloneType),
             dd.Members.ConvertAll(d => CloneMember(d, false)), CloneAttributes(dd.Attributes), dd.IsRefining);
@@ -104,7 +104,7 @@ public virtual TopLevelDecl CloneDeclaration(TopLevelDecl d, ModuleDefinition ne
         var dd = (IndDatatypeDecl)d;
         var tps = dd.TypeArgs.ConvertAll(CloneTypeParam);
         var ctors = dd.Ctors.ConvertAll(CloneCtor);
-        var dt = new IndDatatypeDecl(Range(dd.RangeToken), dd.NameNode.Clone(this), newParent, tps, ctors,
+        var dt = new IndDatatypeDecl(Origin(dd.Origin), dd.NameNode.Clone(this), newParent, tps, ctors,
           dd.ParentTraits.ConvertAll(CloneType),
           dd.Members.ConvertAll(d => CloneMember(d, false)), CloneAttributes(dd.Attributes), dd.IsRefining);
         return dt;
@@ -112,7 +112,7 @@ public virtual TopLevelDecl CloneDeclaration(TopLevelDecl d, ModuleDefinition ne
         var dd = (CoDatatypeDecl)d;
         var tps = dd.TypeArgs.ConvertAll(CloneTypeParam);
         var ctors = dd.Ctors.ConvertAll(CloneCtor);
-        var dt = new CoDatatypeDecl(Range(dd.RangeToken), dd.NameNode.Clone(this), newParent, tps, ctors,
+        var dt = new CoDatatypeDecl(Origin(dd.Origin), dd.NameNode.Clone(this), newParent, tps, ctors,
           dd.ParentTraits.ConvertAll(CloneType),
           dd.Members.ConvertAll(d => CloneMember(d, false)), CloneAttributes(dd.Attributes), dd.IsRefining);
         return dt;
@@ -129,7 +129,7 @@ public virtual TopLevelDecl CloneDeclaration(TopLevelDecl d, ModuleDefinition ne
         var ens = dd.Ensures.ConvertAll(CloneAttributedExpr);
         var yens = dd.YieldEnsures.ConvertAll(CloneAttributedExpr);
         var body = CloneBlockStmt(dd.Body);
-        var iter = new IteratorDecl(Range(dd.RangeToken), dd.NameNode.Clone(this), newParent,
+        var iter = new IteratorDecl(Origin(dd.Origin), dd.NameNode.Clone(this), newParent,
           tps, ins, outs, reads, mod, decr,
           req, ens, yreq, yens,
           body, CloneAttributes(dd.Attributes), dd.SignatureEllipsis);
@@ -138,7 +138,7 @@ public virtual TopLevelDecl CloneDeclaration(TopLevelDecl d, ModuleDefinition ne
         var dd = (TraitDecl)d;
         var tps = dd.TypeArgs.ConvertAll(CloneTypeParam);
         var mm = dd.Members.ConvertAll(member => CloneMember(member, false));
-        var cl = new TraitDecl(Range(dd.RangeToken), dd.NameNode.Clone(this), newParent, tps, mm,
+        var cl = new TraitDecl(Origin(dd.Origin), dd.NameNode.Clone(this), newParent, tps, mm,
           CloneAttributes(dd.Attributes), dd.IsRefining, dd.ParentTraits.ConvertAll(CloneType));
         return cl;
       } else if (d is DefaultClassDecl) {
@@ -150,7 +150,7 @@ public virtual TopLevelDecl CloneDeclaration(TopLevelDecl d, ModuleDefinition ne
         var dd = (ClassDecl)d;
         var tps = dd.TypeArgs.ConvertAll(CloneTypeParam);
         var mm = dd.Members.ConvertAll(member => CloneMember(member, false));
-        return new ClassDecl(Range(dd.RangeToken), dd.NameNode.Clone(this), newParent, tps, mm,
+        return new ClassDecl(Origin(dd.Origin), dd.NameNode.Clone(this), newParent, tps, mm,
           CloneAttributes(dd.Attributes), dd.IsRefining, dd.ParentTraits.ConvertAll(CloneType));
       } else if (d is ModuleDecl) {
         if (d is LiteralModuleDecl moduleDecl) {
@@ -188,13 +188,13 @@ public TypeParameter.TypeParameterCharacteristics CloneTPChar(
     }
 
     public DatatypeCtor CloneCtor(DatatypeCtor ct) {
-      return new DatatypeCtor(Range(ct.RangeToken), ct.NameNode.Clone(this), ct.IsGhost,
+      return new DatatypeCtor(Origin(ct.Origin), ct.NameNode.Clone(this), ct.IsGhost,
         ct.Formals.ConvertAll(bv => CloneFormal(bv, false)), CloneAttributes(ct.Attributes));
     }
 
     public TypeParameter CloneTypeParam(TypeParameter tp) {
       return (TypeParameter)typeParameterClones.GetOrCreate(tp,
-        () => new TypeParameter(Range(tp.RangeToken), tp.NameNode.Clone(this), tp.VarianceSyntax,
+        () => new TypeParameter(Origin(tp.Origin), tp.NameNode.Clone(this), tp.VarianceSyntax,
           CloneTPChar(tp.Characteristics), tp.TypeBounds.ConvertAll(CloneType)));
     }
 
@@ -237,7 +237,7 @@ public virtual Type CloneType(Type t) {
         return new MapType(this, mapType);
       } else if (t is ArrowType) {
         var tt = (ArrowType)t;
-        return new ArrowType(Tok(tt.tok), tt.Args.ConvertAll(CloneType), CloneType(tt.Result));
+        return new ArrowType(Origin(tt.tok), tt.Args.ConvertAll(CloneType), CloneType(tt.Result));
       } else if (t is UserDefinedType) {
         var tt = (UserDefinedType)t;
 #if TEST_TYPE_SYNONYM_TRANSPARENCY
@@ -269,10 +269,10 @@ public virtual Type CloneType(Type t) {
     public virtual Formal CloneFormal(Formal formal, bool isReference) {
       return (Formal)clones.GetOrCreate(formal, () => isReference
        ? formal
-       : new Formal(Tok(formal.tok), formal.Name, CloneType(formal.Type), formal.InParam, formal.IsGhost,
+       : new Formal(Origin(formal.tok), formal.Name, CloneType(formal.Type), formal.InParam, formal.IsGhost,
          CloneExpr(formal.DefaultValue), CloneAttributes(formal.Attributes),
          formal.IsOld, formal.IsNameOnly, formal.IsOlder, formal.NameForCompilation) {
-         RangeToken = formal.RangeToken,
+         RangeOrigin = formal.Origin,
          IsTypeExplicit = formal.IsTypeExplicit
        });
     }
@@ -283,7 +283,7 @@ public virtual BoundVar CloneBoundVar(BoundVar bv, bool isReference) {
           return bv;
         }
 
-        var bvNew = new BoundVar(Tok(bv.tok), bv.Name, CloneType(bv.SyntacticType));
+        var bvNew = new BoundVar(Origin(bv.tok), bv.Name, CloneType(bv.SyntacticType));
         bvNew.IsGhost = bv.IsGhost;
         return bvNew;
       });
@@ -335,9 +335,9 @@ public Attributes CloneAttributes(Attributes attrs) {
         // skip this attribute, since it would have been produced during resolution
         return CloneAttributes(attrs.Prev);
       } else if (attrs is UserSuppliedAttributes usa) {
-        return new UserSuppliedAttributes(Tok(usa.tok), Tok(usa.OpenBrace), Tok(usa.CloseBrace),
+        return new UserSuppliedAttributes(Origin(usa.tok), Origin(usa.OpenBrace), Origin(usa.CloseBrace),
           attrs.Args.ConvertAll(CloneExpr), CloneAttributes(attrs.Prev)) {
-          RangeToken = Tok(usa.RangeToken)
+          RangeOrigin = Origin(usa.Origin)
         };
       } else if (attrs is UserSuppliedAtAttribute usaa) {
         var arg = CloneExpr(usaa.Arg);
@@ -345,27 +345,27 @@ public Attributes CloneAttributes(Attributes attrs) {
           arg.Type = usaa.Arg.Type;
           arg.PreType = usaa.Arg.PreType;
         }
-        return new UserSuppliedAtAttribute(Tok(usaa.tok), arg, CloneAttributes(usaa.Prev)) {
-          RangeToken = Tok(usaa.RangeToken),
+        return new UserSuppliedAtAttribute(Origin(usaa.tok), arg, CloneAttributes(usaa.Prev)) {
+          RangeOrigin = Origin(usaa.Origin),
           Builtin = usaa.Builtin
         };
       } else {
         return new Attributes(attrs.Name, attrs.Args.ConvertAll(CloneExpr), CloneAttributes(attrs.Prev)) {
-          RangeToken = Tok(attrs.RangeToken)
+          RangeOrigin = Origin(attrs.Origin)
         };
       }
     }
 
     public AttributedExpression CloneAttributedExpr(AttributedExpression expr) {
-      var mfe = new AttributedExpression(CloneExpr(expr.E),
-        expr.Label == null ? null : new AssertLabel(Tok(expr.Label.Tok), expr.Label.Name),
+      var mfe = new AttributedExpression(Origin(expr.Origin), CloneExpr(expr.E),
+        expr.Label == null ? null : new AssertLabel(Origin(expr.Label.Tok), expr.Label.Name),
         CloneAttributes(expr.Attributes));
       mfe.Attributes = CloneAttributes(expr.Attributes);
       return mfe;
     }
 
     public virtual ActualBinding CloneActualBinding(ActualBinding binding) {
-      return new ActualBinding(binding.FormalParameterName == null ? null : Tok(binding.FormalParameterName),
+      return new ActualBinding(binding.FormalParameterName,
         CloneExpr(binding.Actual));
     }
 
@@ -384,13 +384,13 @@ public virtual Expression CloneExpr(Expression expr) {
     public MatchCaseExpr CloneMatchCaseExpr(MatchCaseExpr c) {
       Contract.Requires(c != null);
       Contract.Requires(c.Arguments != null);
-      return new MatchCaseExpr(Tok(c.tok), c.Ctor, c.FromBoundVar,
+      return new MatchCaseExpr(Origin(c.tok), c.Ctor, c.FromBoundVar,
         c.Arguments.ConvertAll(bv => CloneBoundVar(bv, false)), CloneExpr(c.Body), CloneAttributes(c.Attributes));
     }
 
     public NestedMatchCaseExpr CloneNestedMatchCaseExpr(NestedMatchCaseExpr c) {
       Contract.Requires(c != null);
-      return new NestedMatchCaseExpr(Tok(c.Tok), CloneExtendedPattern(c.Pat), CloneExpr(c.Body),
+      return new NestedMatchCaseExpr(Origin(c.Tok), CloneExtendedPattern(c.Pat), CloneExpr(c.Body),
         CloneAttributes(c.Attributes));
     }
 
@@ -418,7 +418,7 @@ public virtual BlockStmt CloneBlockStmt(BlockStmt stmt) {
       if (stmt == null) {
         return null;
       } else {
-        return new BlockStmt(Tok(stmt.RangeToken), stmt.Body.ConvertAll(stmt1 => CloneStmt(stmt1, false)));
+        return new BlockStmt(Origin(stmt.Origin), stmt.Body.ConvertAll(stmt1 => CloneStmt(stmt1, false)));
       }
     }
 
@@ -426,8 +426,8 @@ public virtual DividedBlockStmt CloneDividedBlockStmt(DividedBlockStmt stmt) {
       if (stmt == null) {
         return null;
       } else {
-        return new DividedBlockStmt(Tok(stmt.RangeToken), stmt.BodyInit.ConvertAll(stmt1 => CloneStmt(stmt1, false)),
-          stmt.SeparatorTok == null ? null : Tok(stmt.SeparatorTok), stmt.BodyProper.ConvertAll(stmt1 => CloneStmt(stmt1, false)));
+        return new DividedBlockStmt(Origin(stmt.Origin), stmt.BodyInit.ConvertAll(stmt1 => CloneStmt(stmt1, false)),
+          stmt.SeparatorTok == null ? null : Origin(stmt.SeparatorTok), stmt.BodyProper.ConvertAll(stmt1 => CloneStmt(stmt1, false)));
       }
     }
 
@@ -461,7 +461,7 @@ public virtual Statement CloneStmt(Statement stmt, bool isReference) {
     public MatchCaseStmt CloneMatchCaseStmt(MatchCaseStmt c) {
       Contract.Requires(c != null);
       Contract.Assert(c.Arguments != null);
-      return new MatchCaseStmt(Tok(c.RangeToken), c.Ctor, c.FromBoundVar,
+      return new MatchCaseStmt(Origin(c.Origin), c.Ctor, c.FromBoundVar,
         c.Arguments.ConvertAll(v => CloneBoundVar(v, false)),
         c.Body.ConvertAll(stmt => CloneStmt(stmt, false)), CloneAttributes(c.Attributes));
     }
@@ -505,26 +505,26 @@ public void AddStmtLabels(Statement s, LList<Label> node) {
         if (node.Data.Name == null) {
           // this indicates an implicit-target break statement that has been resolved; don't add it
         } else {
-          s.Labels = new LList<Label>(new Label(Tok(node.Data.Tok), node.Data.Name), s.Labels);
+          s.Labels = new LList<Label>(new Label(Origin(node.Data.Tok), node.Data.Name), s.Labels);
         }
       }
     }
 
     public GuardedAlternative CloneGuardedAlternative(GuardedAlternative alt) {
-      return new GuardedAlternative(Tok(alt.Tok), alt.IsBindingGuard, CloneExpr(alt.Guard),
+      return new GuardedAlternative(Origin(alt.Tok), alt.IsBindingGuard, CloneExpr(alt.Guard),
         alt.Body.ConvertAll(stmt => CloneStmt(stmt, false)), CloneAttributes(alt.Attributes));
     }
 
     public virtual Field CloneField(Field f) {
       Contract.Requires(f != null);
       return f switch {
-        ConstantField c => new ConstantField(Range(c.RangeToken), c.NameNode.Clone(this), CloneExpr(c.Rhs),
+        ConstantField c => new ConstantField(Origin(c.Origin), c.NameNode.Clone(this), CloneExpr(c.Rhs),
           c.HasStaticKeyword, c.IsGhost, c.IsOpaque, CloneType(c.Type), CloneAttributes(c.Attributes)),
         // We don't expect a SpecialField to ever be cloned. However, it can happen for malformed programs, for example if
         // an iterator in a refined module is replaced by a class in the refining module.
-        SpecialField s => new SpecialField(Range(s.RangeToken), s.Name, s.SpecialId, s.IdParam, s.IsGhost, s.IsMutable,
+        SpecialField s => new SpecialField(Origin(s.Origin), s.Name, s.SpecialId, s.IdParam, s.IsGhost, s.IsMutable,
           s.IsUserMutable, CloneType(s.Type), CloneAttributes(s.Attributes)),
-        _ => new Field(Range(f.RangeToken), f.NameNode.Clone(this), f.HasStaticKeyword, f.IsGhost, f.IsMutable,
+        _ => new Field(Origin(f.Origin), f.NameNode.Clone(this), f.HasStaticKeyword, f.IsGhost, f.IsMutable,
           f.IsUserMutable, CloneType(f.Type), CloneAttributes(f.Attributes))
       };
     }
@@ -544,34 +544,34 @@ public virtual Function CloneFunction(Function f, string newName = null) {
         newName = f.Name;
       }
 
-      var newNameNode = new Name(Range(f.NameNode.RangeToken), newName);
+      var newNameNode = new Name(Origin(f.NameNode.Origin), newName);
 
       if (f is Predicate) {
-        return new Predicate(Range(f.RangeToken), newNameNode, f.HasStaticKeyword, f.IsGhost, f.IsOpaque, tps, formals,
+        return new Predicate(Origin(f.Origin), newNameNode, f.HasStaticKeyword, f.IsGhost, f.IsOpaque, tps, formals,
           result,
           req, reads, ens, decreases, body, Predicate.BodyOriginKind.OriginalOrInherited,
-          f.ByMethodTok == null ? null : Tok(f.ByMethodTok), byMethodBody,
+          f.ByMethodTok == null ? null : Origin(f.ByMethodTok), byMethodBody,
           CloneAttributes(f.Attributes), null);
       } else if (f is LeastPredicate) {
-        return new LeastPredicate(Range(f.RangeToken), newNameNode, f.HasStaticKeyword, f.IsOpaque,
+        return new LeastPredicate(Origin(f.Origin), newNameNode, f.HasStaticKeyword, f.IsOpaque,
           ((LeastPredicate)f).TypeOfK, tps, formals, result,
           req, reads, ens, body, CloneAttributes(f.Attributes), null);
       } else if (f is GreatestPredicate greatestPredicate) {
-        return new GreatestPredicate(Range(f.RangeToken), newNameNode, f.HasStaticKeyword, f.IsOpaque,
+        return new GreatestPredicate(Origin(f.Origin), newNameNode, f.HasStaticKeyword, f.IsOpaque,
           ((GreatestPredicate)f).TypeOfK, tps, formals, result,
           req, reads, ens, body, CloneAttributes(f.Attributes), null);
       } else if (f is TwoStatePredicate) {
-        return new TwoStatePredicate(Range(f.RangeToken), newNameNode, f.HasStaticKeyword, f.IsOpaque, tps, formals,
+        return new TwoStatePredicate(Origin(f.Origin), newNameNode, f.HasStaticKeyword, f.IsOpaque, tps, formals,
           result,
           req, reads, ens, decreases, body, CloneAttributes(f.Attributes), null);
       } else if (f is TwoStateFunction) {
-        return new TwoStateFunction(Range(f.RangeToken), newNameNode, f.HasStaticKeyword, f.IsOpaque, tps, formals,
+        return new TwoStateFunction(Origin(f.Origin), newNameNode, f.HasStaticKeyword, f.IsOpaque, tps, formals,
           result, CloneType(f.ResultType),
           req, reads, ens, decreases, body, CloneAttributes(f.Attributes), null);
       } else {
-        return new Function(Range(f.RangeToken), newNameNode, f.HasStaticKeyword, f.IsGhost, f.IsOpaque, tps, formals,
+        return new Function(Origin(f.Origin), newNameNode, f.HasStaticKeyword, f.IsGhost, f.IsOpaque, tps, formals,
           result, CloneType(f.ResultType),
-          req, reads, ens, decreases, body, f.ByMethodTok == null ? null : Tok(f.ByMethodTok), byMethodBody,
+          req, reads, ens, decreases, body, f.ByMethodTok == null ? null : Origin(f.ByMethodTok), byMethodBody,
           CloneAttributes(f.Attributes), null);
       }
     }
@@ -596,21 +596,13 @@ public virtual BlockStmt CloneMethodBody(Method m) {
       }
     }
 
-    public virtual RangeToken Range(RangeToken range) {
-      if (range == null) {
+    public virtual IOrigin Origin(IOrigin origin) {
+      if (origin == null) {
         return null;
       }
-      return new RangeToken(Tok(range.StartToken), Tok(range.EndToken));
-    }
-
-    public virtual IOrigin Tok(IOrigin tok) {
-      Contract.Requires(tok != null);
-      return tok;
-    }
 
-    public RangeToken Tok(RangeToken tok) {
-      Contract.Requires(tok != null);
-      return new RangeToken(Tok(tok.StartToken), Tok(tok.EndToken));
+      Contract.Requires(origin != null);
+      return origin;
     }
 
     public virtual AttributedToken AttributedTok(AttributedToken tok) {
@@ -618,14 +610,14 @@ public virtual AttributedToken AttributedTok(AttributedToken tok) {
         return null;
       }
 
-      return new AttributedToken(Tok(tok.Token), CloneAttributes(tok.Attrs));
+      return tok with { Attrs = CloneAttributes(tok.Attrs) };
     }
   }
 
   public class ClonerKeepParensExpressions : Cloner {
     public override Expression CloneExpr(Expression expr) {
       if (expr is ParensExpression parensExpression) {
-        return new ParensExpression(Tok(parensExpression.tok), CloneExpr(parensExpression.E));
+        return new ParensExpression(Origin(parensExpression.tok), CloneExpr(parensExpression.E));
       }
 
       return base.CloneExpr(expr);
diff --git a/Source/DafnyCore/AST/DafnyInterface.dfy b/Source/DafnyCore/AST/DafnyInterface.dfy
index c39e496bf8b..daf14ecfec7 100644
--- a/Source/DafnyCore/AST/DafnyInterface.dfy
+++ b/Source/DafnyCore/AST/DafnyInterface.dfy
@@ -1,6 +1,6 @@
 include "System.dfy"
 
-// Interface with existing Dafny code (IOrigin)
+// Interface with existing Dafny code (Token)
 @Compile(false)
 @Options("-functionSyntax:4")
 module {:extern "Microsoft.Dafny"} MicrosoftDafny {
diff --git a/Source/DafnyCore/AST/Expressions/Applications/ActualBindings.cs b/Source/DafnyCore/AST/Expressions/Applications/ActualBindings.cs
index 0005ef862d4..7bb20e0fdf5 100644
--- a/Source/DafnyCore/AST/Expressions/Applications/ActualBindings.cs
+++ b/Source/DafnyCore/AST/Expressions/Applications/ActualBindings.cs
@@ -14,7 +14,7 @@ public ActualBindings(List<ActualBinding> argumentBindings) {
 
   public ActualBindings(Cloner cloner, ActualBindings original) {
     ArgumentBindings = original.ArgumentBindings.Select(actualBinding => new ActualBinding(
-      actualBinding.FormalParameterName == null ? null : cloner.Tok((IOrigin)actualBinding.FormalParameterName),
+      actualBinding.FormalParameterName,
       cloner.CloneExpr(actualBinding.Actual))).ToList();
     if (cloner.CloneResolvedFields) {
       arguments = original.Arguments?.Select(cloner.CloneExpr).ToList();
@@ -44,7 +44,7 @@ public void AcceptArgumentExpressionsAsExactParameterList(List<Expression> args
 }
 
 public class ActualBinding : TokenNode {
-  public readonly IOrigin /*?*/ FormalParameterName;
+  public readonly Token /*?*/ FormalParameterName;
   public readonly Expression Actual;
   public readonly bool IsGhost;
 
@@ -52,7 +52,7 @@ public class ActualBinding : TokenNode {
 
   public override IEnumerable<INode> PreResolveChildren => Children;
 
-  public ActualBinding(IOrigin /*?*/ formalParameterName, Expression actual, bool isGhost = false) {
+  public ActualBinding(Token /*?*/ formalParameterName, Expression actual, bool isGhost = false) {
     Contract.Requires(actual != null);
     FormalParameterName = formalParameterName;
     Actual = actual;
diff --git a/Source/DafnyCore/AST/Expressions/Applications/ApplyExpr.cs b/Source/DafnyCore/AST/Expressions/Applications/ApplyExpr.cs
index 5ef507ad35a..e1a9f3c481d 100644
--- a/Source/DafnyCore/AST/Expressions/Applications/ApplyExpr.cs
+++ b/Source/DafnyCore/AST/Expressions/Applications/ApplyExpr.cs
@@ -18,15 +18,15 @@ public override IEnumerable<Expression> SubExpressions {
     }
   }
 
-  public IOrigin CloseParen;
+  public Token CloseParen;
 
   public ApplyExpr(Cloner cloner, ApplyExpr original) : base(cloner, original) {
     Function = cloner.CloneExpr(original.Function);
     Args = original.Args.ConvertAll(cloner.CloneExpr);
-    CloseParen = cloner.Tok(original.CloseParen);
+    CloseParen = original.CloseParen;
   }
 
-  public ApplyExpr(IOrigin tok, Expression fn, List<Expression> args, IOrigin closeParen)
+  public ApplyExpr(IOrigin tok, Expression fn, List<Expression> args, Token closeParen)
     : base(tok) {
     Function = fn;
     Args = args;
diff --git a/Source/DafnyCore/AST/Expressions/Applications/ApplySuffix.cs b/Source/DafnyCore/AST/Expressions/Applications/ApplySuffix.cs
index f31f267f7ed..d4ffd7f61a8 100644
--- a/Source/DafnyCore/AST/Expressions/Applications/ApplySuffix.cs
+++ b/Source/DafnyCore/AST/Expressions/Applications/ApplySuffix.cs
@@ -9,7 +9,7 @@ namespace Microsoft.Dafny;
 /// </summary>
 public class ApplySuffix : SuffixExpr, ICloneable<ApplySuffix>, ICanFormat {
   public readonly IOrigin/*?*/ AtTok;
-  public readonly IOrigin CloseParen;
+  public readonly Token CloseParen;
   public readonly ActualBindings Bindings;
   public List<Expression> Args => Bindings.Arguments;
   [FilledInDuringResolution] public MethodCallInformation MethodCallInfo = null; // resolution will set to a non-null value if ApplySuffix makes a method call
@@ -29,13 +29,13 @@ public ApplySuffix Clone(Cloner cloner) {
 
   public ApplySuffix(Cloner cloner, ApplySuffix original) :
     base(cloner, original) {
-    AtTok = original.AtTok == null ? null : cloner.Tok(original.AtTok);
-    CloseParen = cloner.Tok(original.CloseParen);
+    AtTok = original.AtTok == null ? null : cloner.Origin(original.AtTok);
+    CloseParen = original.CloseParen;
     FormatTokens = original.FormatTokens;
     Bindings = new ActualBindings(cloner, original.Bindings);
   }
 
-  public ApplySuffix(IOrigin tok, IOrigin/*?*/ atLabel, Expression lhs, List<ActualBinding> args, IOrigin closeParen)
+  public ApplySuffix(IOrigin tok, IOrigin/*?*/ atLabel, Expression lhs, List<ActualBinding> args, Token closeParen)
     : base(tok, lhs) {
     Contract.Requires(tok != null);
     Contract.Requires(lhs != null);
@@ -69,7 +69,7 @@ public override IEnumerable<Expression> PreResolveSubExpressions {
   public static Expression MakeRawApplySuffix(IOrigin tok, string name, List<Expression> args) {
     var nameExpr = new NameSegment(tok, name, null);
     var argBindings = args.ConvertAll(arg => new ActualBinding(null, arg));
-    return new ApplySuffix(tok, null, nameExpr, argBindings, tok);
+    return new ApplySuffix(tok, null, nameExpr, argBindings, Token.NoToken);
   }
 
   public bool SetIndent(int indentBefore, TokenNewIndentCollector formatter) {
diff --git a/Source/DafnyCore/AST/Expressions/Applications/FunctionCallExpr.cs b/Source/DafnyCore/AST/Expressions/Applications/FunctionCallExpr.cs
index e60bd648a9e..24dfbbf8db1 100644
--- a/Source/DafnyCore/AST/Expressions/Applications/FunctionCallExpr.cs
+++ b/Source/DafnyCore/AST/Expressions/Applications/FunctionCallExpr.cs
@@ -7,8 +7,8 @@ namespace Microsoft.Dafny;
 public class FunctionCallExpr : Expression, IHasReferences, ICloneable<FunctionCallExpr> {
   public string Name;
   public readonly Expression Receiver;
-  public readonly IOrigin OpenParen;  // can be null if Args.Count == 0
-  public readonly IOrigin CloseParen;
+  public readonly Token OpenParen;  // can be null if Args.Count == 0
+  public readonly Token CloseParen;
   public readonly Label/*?*/ AtLabel;
   public readonly ActualBindings Bindings;
   public List<Expression> Args => Bindings.Arguments;
@@ -74,7 +74,7 @@ void ObjectInvariant() {
 
   [FilledInDuringResolution] public Function Function;
 
-  public FunctionCallExpr(IOrigin tok, string fn, Expression receiver, IOrigin openParen, IOrigin closeParen, [Captured] List<ActualBinding> args, Label/*?*/ atLabel = null)
+  public FunctionCallExpr(IOrigin tok, string fn, Expression receiver, Token openParen, Token closeParen, [Captured] List<ActualBinding> args, Label/*?*/ atLabel = null)
     : this(tok, fn, receiver, openParen, closeParen, new ActualBindings(args), atLabel) {
     Contract.Requires(tok != null);
     Contract.Requires(fn != null);
@@ -84,7 +84,7 @@ public FunctionCallExpr(IOrigin tok, string fn, Expression receiver, IOrigin ope
     Contract.Ensures(type == null);
   }
 
-  public FunctionCallExpr(IOrigin tok, string fn, Expression receiver, IOrigin openParen, IOrigin closeParen, [Captured] ActualBindings bindings, Label/*?*/ atLabel = null)
+  public FunctionCallExpr(IOrigin tok, string fn, Expression receiver, Token openParen, Token closeParen, [Captured] ActualBindings bindings, Label/*?*/ atLabel = null)
     : base(tok) {
     Contract.Requires(tok != null);
     Contract.Requires(fn != null);
@@ -106,7 +106,7 @@ public FunctionCallExpr(IOrigin tok, string fn, Expression receiver, IOrigin ope
   /// This constructor is intended to be used when constructing a resolved FunctionCallExpr. The "args" are expected
   /// to be already resolved, and are all given positionally.
   /// </summary>
-  public FunctionCallExpr(IOrigin tok, string fn, Expression receiver, IOrigin openParen, IOrigin closeParen, [Captured] List<Expression> args,
+  public FunctionCallExpr(IOrigin tok, string fn, Expression receiver, Token openParen, Token closeParen, [Captured] List<Expression> args,
     Label /*?*/ atLabel = null)
     : this(tok, fn, receiver, openParen, closeParen, args.ConvertAll(e => new ActualBinding(null, e)), atLabel) {
     Bindings.AcceptArgumentExpressionsAsExactParameterList();
@@ -119,8 +119,8 @@ public FunctionCallExpr Clone(Cloner cloner) {
   public FunctionCallExpr(Cloner cloner, FunctionCallExpr original) : base(cloner, original) {
     Name = original.Name;
     Receiver = cloner.CloneExpr(original.Receiver);
-    OpenParen = original.OpenParen == null ? null : cloner.Tok(original.OpenParen);
-    CloseParen = original.CloseParen == null ? null : cloner.Tok(original.CloseParen);
+    OpenParen = original.OpenParen == null ? null : original.OpenParen;
+    CloseParen = original.CloseParen == null ? null : original.CloseParen;
     Bindings = new ActualBindings(cloner, original.Bindings);
     AtLabel = original.AtLabel;
 
diff --git a/Source/DafnyCore/AST/Expressions/Applications/SeqSelectExpr.cs b/Source/DafnyCore/AST/Expressions/Applications/SeqSelectExpr.cs
index 0b489c622fe..434ebbd70ae 100644
--- a/Source/DafnyCore/AST/Expressions/Applications/SeqSelectExpr.cs
+++ b/Source/DafnyCore/AST/Expressions/Applications/SeqSelectExpr.cs
@@ -8,14 +8,14 @@ public class SeqSelectExpr : Expression, ICloneable<SeqSelectExpr> {
   public readonly Expression Seq;
   public readonly Expression E0;
   public readonly Expression E1;
-  public readonly IOrigin CloseParen;
+  public readonly Token CloseParen;
 
   public SeqSelectExpr(Cloner cloner, SeqSelectExpr original) : base(cloner, original) {
     SelectOne = original.SelectOne;
     Seq = cloner.CloneExpr(original.Seq);
     E0 = cloner.CloneExpr(original.E0);
     E1 = cloner.CloneExpr(original.E1);
-    CloseParen = cloner.Tok(original.CloseParen);
+    CloseParen = original.CloseParen;
   }
 
   [ContractInvariantMethod]
@@ -24,7 +24,7 @@ void ObjectInvariant() {
     Contract.Invariant(!SelectOne || E1 == null);
   }
 
-  public SeqSelectExpr(IOrigin tok, bool selectOne, Expression seq, Expression e0, Expression e1, IOrigin closeParen)
+  public SeqSelectExpr(IOrigin tok, bool selectOne, Expression seq, Expression e0, Expression e1, Token closeParen)
     : base(tok) {
     Contract.Requires(tok != null);
     Contract.Requires(seq != null);
diff --git a/Source/DafnyCore/AST/Expressions/AttributedExpression.cs b/Source/DafnyCore/AST/Expressions/AttributedExpression.cs
index b6b9fdeb0c9..f6db1aac057 100644
--- a/Source/DafnyCore/AST/Expressions/AttributedExpression.cs
+++ b/Source/DafnyCore/AST/Expressions/AttributedExpression.cs
@@ -4,7 +4,7 @@
 
 namespace Microsoft.Dafny;
 
-public class AttributedExpression : TokenNode, IAttributeBearingDeclaration {
+public class AttributedExpression : RangeNode, IAttributeBearingDeclaration {
   public readonly Expression E;
   public readonly AssertLabel/*?*/ Label;
 
@@ -25,26 +25,24 @@ public Attributes Attributes {
 
   string IAttributeBearingDeclaration.WhatKind => "expression";
 
-  public override RangeToken RangeToken => E.RangeToken;
-
   public bool HasAttributes() {
     return Attributes != null;
   }
 
-  public AttributedExpression(Expression e)
-    : this(e, null) {
+  public AttributedExpression(IOrigin origin, Expression e)
+    : this(origin, e, null) {
     Contract.Requires(e != null);
   }
 
-  public AttributedExpression(Expression e, Attributes attrs) : this(e, null, attrs) {
+  public AttributedExpression(IOrigin origin, Expression e, Attributes attrs) : this(origin, e, null, attrs) {
   }
 
-  public AttributedExpression(Expression e, AssertLabel/*?*/ label, Attributes attrs) {
+  public AttributedExpression(IOrigin origin, Expression e, AssertLabel/*?*/ label, Attributes attrs)
+   : base(origin) {
     Contract.Requires(e != null);
     E = e;
     Label = label;
     Attributes = attrs;
-    this.tok = e.Tok;
   }
 
   public void AddCustomizedErrorMessage(IOrigin tok, string s) {
diff --git a/Source/DafnyCore/AST/Expressions/Comprehensions/ComprehensionExpr.cs b/Source/DafnyCore/AST/Expressions/Comprehensions/ComprehensionExpr.cs
index 4c3d88b6e68..e49371e7024 100644
--- a/Source/DafnyCore/AST/Expressions/Comprehensions/ComprehensionExpr.cs
+++ b/Source/DafnyCore/AST/Expressions/Comprehensions/ComprehensionExpr.cs
@@ -54,7 +54,7 @@ public List<BoundVar> UncompilableBoundVars() {
     return BoundedPool.MissingBounds(BoundVars, Bounds, v);
   }
 
-  public ComprehensionExpr(IOrigin tok, RangeToken rangeOrigin, List<BoundVar> bvars, Expression range, Expression term, Attributes attrs)
+  public ComprehensionExpr(IOrigin tok, IOrigin rangeOrigin, List<BoundVar> bvars, Expression range, Expression term, Attributes attrs)
     : base(tok) {
     Contract.Requires(tok != null);
     Contract.Requires(cce.NonNullElements(bvars));
@@ -65,15 +65,15 @@ public ComprehensionExpr(IOrigin tok, RangeToken rangeOrigin, List<BoundVar> bva
     Term = term;
     Attributes = attrs;
     BodyStartTok = tok;
-    RangeToken = rangeOrigin;
+    RangeOrigin = rangeOrigin;
   }
 
   protected ComprehensionExpr(Cloner cloner, ComprehensionExpr original) : base(cloner, original) {
     BoundVars = original.BoundVars.Select(bv => cloner.CloneBoundVar(bv, false)).ToList();
     Range = cloner.CloneExpr(original.Range);
     Attributes = cloner.CloneAttributes(original.Attributes);
-    BodyStartTok = cloner.Tok(original.BodyStartTok);
-    RangeToken = cloner.Tok(original.RangeToken);
+    BodyStartTok = cloner.Origin(original.BodyStartTok);
+    RangeOrigin = cloner.Origin(original.Origin);
     Term = cloner.CloneExpr(original.Term);
 
     if (cloner.CloneResolvedFields) {
diff --git a/Source/DafnyCore/AST/Expressions/Comprehensions/ExistsExpr.cs b/Source/DafnyCore/AST/Expressions/Comprehensions/ExistsExpr.cs
index eaa923d1b0f..b7511790241 100644
--- a/Source/DafnyCore/AST/Expressions/Comprehensions/ExistsExpr.cs
+++ b/Source/DafnyCore/AST/Expressions/Comprehensions/ExistsExpr.cs
@@ -7,8 +7,8 @@ public class ExistsExpr : QuantifierExpr, ICloneable<ExistsExpr> {
   public override string WhatKind => "exists expression";
   protected override BinaryExpr.ResolvedOpcode SplitResolvedOp { get { return BinaryExpr.ResolvedOpcode.Or; } }
 
-  public ExistsExpr(IOrigin tok, RangeToken rangeOrigin, List<BoundVar> bvars, Expression range, Expression term, Attributes attrs)
-    : base(tok, rangeOrigin, bvars, range, term, attrs) {
+  public ExistsExpr(IOrigin tok, IOrigin rangeToken, List<BoundVar> bvars, Expression range, Expression term, Attributes attrs)
+    : base(tok, rangeToken, bvars, range, term, attrs) {
     Contract.Requires(cce.NonNullElements(bvars));
     Contract.Requires(tok != null);
     Contract.Requires(term != null);
@@ -60,7 +60,7 @@ public Expression AlphaRename(string prefix) {
     var range = Range == null ? null : s.Substitute(Range);
     var term = s.Substitute(Term);
     var attrs = s.SubstAttributes(Attributes);
-    var ex = new ExistsExpr(tok, RangeToken, bvars, range, term, attrs);
+    var ex = new ExistsExpr(tok, Origin, bvars, range, term, attrs);
     ex.Type = Type.Bool;
     ex.Bounds = s.SubstituteBoundedPoolList(Bounds);
     return ex;
diff --git a/Source/DafnyCore/AST/Expressions/Comprehensions/ForallExpr.cs b/Source/DafnyCore/AST/Expressions/Comprehensions/ForallExpr.cs
index 4c040c44b93..5fdbeefc572 100644
--- a/Source/DafnyCore/AST/Expressions/Comprehensions/ForallExpr.cs
+++ b/Source/DafnyCore/AST/Expressions/Comprehensions/ForallExpr.cs
@@ -7,8 +7,8 @@ public class ForallExpr : QuantifierExpr, ICloneable<ForallExpr> {
   public override string WhatKind => "forall expression";
   protected override BinaryExpr.ResolvedOpcode SplitResolvedOp => BinaryExpr.ResolvedOpcode.And;
 
-  public ForallExpr(IOrigin tok, RangeToken rangeOrigin, List<BoundVar> bvars, Expression range, Expression term, Attributes attrs)
-    : base(tok, rangeOrigin, bvars, range, term, attrs) {
+  public ForallExpr(IOrigin tok, IOrigin rangeToken, List<BoundVar> bvars, Expression range, Expression term, Attributes attrs)
+    : base(tok, rangeToken, bvars, range, term, attrs) {
     Contract.Requires(cce.NonNullElements(bvars));
     Contract.Requires(tok != null);
     Contract.Requires(term != null);
diff --git a/Source/DafnyCore/AST/Expressions/Comprehensions/LambdaExpr.cs b/Source/DafnyCore/AST/Expressions/Comprehensions/LambdaExpr.cs
index d1c58294906..c6cc6e875a1 100644
--- a/Source/DafnyCore/AST/Expressions/Comprehensions/LambdaExpr.cs
+++ b/Source/DafnyCore/AST/Expressions/Comprehensions/LambdaExpr.cs
@@ -10,7 +10,7 @@ public class LambdaExpr : ComprehensionExpr, ICloneable<LambdaExpr>, IFrameScope
 
   public readonly Specification<FrameExpression> Reads;
 
-  public LambdaExpr(IOrigin tok, RangeToken rangeOrigin, List<BoundVar> bvars, Expression requires, Specification<FrameExpression> reads, Expression body)
+  public LambdaExpr(IOrigin tok, IOrigin rangeOrigin, List<BoundVar> bvars, Expression requires, Specification<FrameExpression> reads, Expression body)
     : base(tok, rangeOrigin, bvars, requires, body, null) {
     Contract.Requires(reads != null);
     Reads = reads;
diff --git a/Source/DafnyCore/AST/Expressions/Comprehensions/MapComprehension.cs b/Source/DafnyCore/AST/Expressions/Comprehensions/MapComprehension.cs
index e01bb64a6a0..5a69e6caa68 100644
--- a/Source/DafnyCore/AST/Expressions/Comprehensions/MapComprehension.cs
+++ b/Source/DafnyCore/AST/Expressions/Comprehensions/MapComprehension.cs
@@ -20,7 +20,7 @@ public MapComprehension(Cloner cloner, MapComprehension original) : base(cloner,
     Finite = original.Finite;
   }
 
-  public MapComprehension(IOrigin tok, RangeToken rangeOrigin, bool finite, List<BoundVar> bvars, Expression range, Expression/*?*/ termLeft, Expression termRight, Attributes attrs)
+  public MapComprehension(IOrigin tok, IOrigin rangeOrigin, bool finite, List<BoundVar> bvars, Expression range, Expression/*?*/ termLeft, Expression termRight, Attributes attrs)
     : base(tok, rangeOrigin, bvars, range, termRight, attrs) {
     Contract.Requires(tok != null);
     Contract.Requires(cce.NonNullElements(bvars));
diff --git a/Source/DafnyCore/AST/Expressions/Comprehensions/QuantifierExpr.cs b/Source/DafnyCore/AST/Expressions/Comprehensions/QuantifierExpr.cs
index b9b9f84efb9..4caa4dec868 100644
--- a/Source/DafnyCore/AST/Expressions/Comprehensions/QuantifierExpr.cs
+++ b/Source/DafnyCore/AST/Expressions/Comprehensions/QuantifierExpr.cs
@@ -50,7 +50,8 @@ public String Refresh(string prefix, FreshIdGenerator idGen) {
     return idGen.FreshId(prefix);
   }
 
-  public QuantifierExpr(IOrigin tok, RangeToken rangeOrigin, List<BoundVar> bvars, Expression range, Expression term, Attributes attrs)
+  protected QuantifierExpr(IOrigin tok, IOrigin rangeOrigin, List<BoundVar> bvars, Expression range, Expression term,
+    Attributes attrs)
     : base(tok, rangeOrigin, bvars, range, term, attrs) {
     Contract.Requires(tok != null);
     Contract.Requires(cce.NonNullElements(bvars));
diff --git a/Source/DafnyCore/AST/Expressions/Comprehensions/SetComprehension.cs b/Source/DafnyCore/AST/Expressions/Comprehensions/SetComprehension.cs
index 2482dd95347..4ca975a8c8c 100644
--- a/Source/DafnyCore/AST/Expressions/Comprehensions/SetComprehension.cs
+++ b/Source/DafnyCore/AST/Expressions/Comprehensions/SetComprehension.cs
@@ -27,7 +27,7 @@ public SetComprehension(Cloner cloner, SetComprehension original) : base(cloner,
     Finite = original.Finite;
   }
 
-  public SetComprehension(IOrigin tok, RangeToken rangeOrigin, bool finite, List<BoundVar> bvars, Expression range, Expression/*?*/ term, Attributes attrs)
+  public SetComprehension(IOrigin tok, IOrigin rangeOrigin, bool finite, List<BoundVar> bvars, Expression range, Expression/*?*/ term, Attributes attrs)
     : base(tok, rangeOrigin, bvars, range, term ?? new IdentifierExpr(tok, bvars[0].Name), attrs) {
     Contract.Requires(tok != null);
     Contract.Requires(cce.NonNullElements(bvars));
diff --git a/Source/DafnyCore/AST/Expressions/ConcreteSyntaxExpression.cs b/Source/DafnyCore/AST/Expressions/ConcreteSyntaxExpression.cs
index f0bf4c87107..bcd5399a7c7 100644
--- a/Source/DafnyCore/AST/Expressions/ConcreteSyntaxExpression.cs
+++ b/Source/DafnyCore/AST/Expressions/ConcreteSyntaxExpression.cs
@@ -22,8 +22,8 @@ public Expression ResolvedExpression {
     get => resolvedExpression;
     set {
       resolvedExpression = value;
-      if (RangeOrigin != null && resolvedExpression != null) {
-        resolvedExpression.RangeToken = RangeOrigin;
+      if (rangeToken != null && resolvedExpression != null) {
+        resolvedExpression.RangeOrigin = rangeToken;
       }
     }
   }  // after resolution, manipulation of "this" should proceed as with manipulating "this.ResolvedExpression"
diff --git a/Source/DafnyCore/AST/Expressions/Conditional/NestedMatchCaseStmt.cs b/Source/DafnyCore/AST/Expressions/Conditional/NestedMatchCaseStmt.cs
index fe3dda9c49f..6a91308abc8 100644
--- a/Source/DafnyCore/AST/Expressions/Conditional/NestedMatchCaseStmt.cs
+++ b/Source/DafnyCore/AST/Expressions/Conditional/NestedMatchCaseStmt.cs
@@ -9,8 +9,8 @@ public class NestedMatchCaseStmt : NestedMatchCase, IAttributeBearingDeclaration
   public readonly List<Statement> Body;
   public Attributes Attributes { get; set; }
   string IAttributeBearingDeclaration.WhatKind => "match statement case";
-  public NestedMatchCaseStmt(RangeToken rangeOrigin, ExtendedPattern pat, List<Statement> body) : base(rangeOrigin.StartToken, pat) {
-    RangeToken = rangeOrigin;
+  public NestedMatchCaseStmt(IOrigin rangeOrigin, ExtendedPattern pat, List<Statement> body) : base(rangeOrigin.StartToken, pat) {
+    RangeOrigin = rangeOrigin;
     Contract.Requires(body != null);
     this.Body = body;
     this.Attributes = null;
diff --git a/Source/DafnyCore/AST/Expressions/Conditional/NestedMatchStmt.cs b/Source/DafnyCore/AST/Expressions/Conditional/NestedMatchStmt.cs
index ab5b56ed30b..d10229e4bed 100644
--- a/Source/DafnyCore/AST/Expressions/Conditional/NestedMatchStmt.cs
+++ b/Source/DafnyCore/AST/Expressions/Conditional/NestedMatchStmt.cs
@@ -72,7 +72,7 @@ public override IEnumerable<Expression> NonSpecificationSubExpressions {
     }
   }
 
-  public NestedMatchStmt(RangeToken rangeOrigin, Expression source, [Captured] List<NestedMatchCaseStmt> cases, bool usesOptionalBraces, Attributes attrs = null)
+  public NestedMatchStmt(IOrigin rangeOrigin, Expression source, [Captured] List<NestedMatchCaseStmt> cases, bool usesOptionalBraces, Attributes attrs = null)
     : base(rangeOrigin, attrs) {
     Contract.Requires(source != null);
     Contract.Requires(cce.NonNullElements(cases));
diff --git a/Source/DafnyCore/AST/Expressions/Conditional/Patterns/IdPattern.cs b/Source/DafnyCore/AST/Expressions/Conditional/Patterns/IdPattern.cs
index a056166c177..b3cd90776c3 100644
--- a/Source/DafnyCore/AST/Expressions/Conditional/Patterns/IdPattern.cs
+++ b/Source/DafnyCore/AST/Expressions/Conditional/Patterns/IdPattern.cs
@@ -30,7 +30,7 @@ public void MakeAConstructor() {
     this.Arguments = new List<ExtendedPattern>();
   }
 
-  public IdPattern(Cloner cloner, IdPattern original) : base(cloner.Tok(original.Tok), original.IsGhost) {
+  public IdPattern(Cloner cloner, IdPattern original) : base(cloner.Origin(original.Tok), original.IsGhost) {
     Id = original.Id;
     Arguments = original.Arguments?.Select(cloner.CloneExtendedPattern).ToList();
     HasParenthesis = original.HasParenthesis;
@@ -104,7 +104,7 @@ public override void Resolve(ModuleResolver resolver, ResolutionContext resoluti
       }
 
       if (inStatementContext) {
-        var localVariable = new LocalVariable(RangeToken, Id, null, isGhost) {
+        var localVariable = new LocalVariable(Origin, Id, null, isGhost) {
           type = Type
         };
         BoundVar = localVariable;
diff --git a/Source/DafnyCore/AST/Expressions/Datatypes/DatatypeUpdateExpr.cs b/Source/DafnyCore/AST/Expressions/Datatypes/DatatypeUpdateExpr.cs
index 8594df7edab..5c44745870f 100644
--- a/Source/DafnyCore/AST/Expressions/Datatypes/DatatypeUpdateExpr.cs
+++ b/Source/DafnyCore/AST/Expressions/Datatypes/DatatypeUpdateExpr.cs
@@ -19,7 +19,7 @@ public DatatypeUpdateExpr Clone(Cloner cloner) {
 
   public DatatypeUpdateExpr(Cloner cloner, DatatypeUpdateExpr original) : base(cloner, original) {
     Root = cloner.CloneExpr(original.Root);
-    Updates = original.Updates.Select(t => Tuple.Create(cloner.Tok(t.Item1), t.Item2, cloner.CloneExpr(t.Item3)))
+    Updates = original.Updates.Select(t => Tuple.Create(cloner.Origin(t.Item1), t.Item2, cloner.CloneExpr(t.Item3)))
       .ToList();
 
     if (cloner.CloneResolvedFields) {
diff --git a/Source/DafnyCore/AST/Expressions/DefaultValueExpression.cs b/Source/DafnyCore/AST/Expressions/DefaultValueExpression.cs
index e772dad66d9..6720e00687a 100644
--- a/Source/DafnyCore/AST/Expressions/DefaultValueExpression.cs
+++ b/Source/DafnyCore/AST/Expressions/DefaultValueExpression.cs
@@ -41,7 +41,6 @@ protected DefaultValueExpression(IOrigin tok, Formal formal, Expression/*?*/ rec
     this.formal = formal;
     this.receiver = receiver;
     this.substMap = substMap;
-    RangeToken = new RangeToken(tok, tok);
   }
 
   protected DefaultValueExpression(Cloner cloner, DefaultValueExpression original) : base(cloner, original) {
diff --git a/Source/DafnyCore/AST/Expressions/Expression.cs b/Source/DafnyCore/AST/Expressions/Expression.cs
index 2ce4603a867..0997888262d 100644
--- a/Source/DafnyCore/AST/Expressions/Expression.cs
+++ b/Source/DafnyCore/AST/Expressions/Expression.cs
@@ -102,8 +102,8 @@ public Expression(IOrigin tok) {
 
   protected Expression(Cloner cloner, Expression original) {
 
-    tok = cloner.Tok(original.tok);
-    RangeToken = cloner.Range(original.RangeToken);
+    tok = cloner.Origin(original.tok);
+    RangeOrigin = cloner.Origin(original.Origin);
 
     if (cloner.CloneResolvedFields && original.Type != null) {
       Type = original.Type;
@@ -752,7 +752,7 @@ public static Expression CreateResolvedCall(IOrigin tok, Expression receiver, Fu
     Contract.Requires(function.Ins.Count == arguments.Count);
     Contract.Requires(function.TypeArgs.Count == typeArguments.Count);
 
-    var call = new FunctionCallExpr(tok, function.Name, receiver, tok, tok, arguments) {
+    var call = new FunctionCallExpr(tok, function.Name, receiver, Token.NoToken, Token.NoToken, arguments) {
       Function = function,
       Type = function.ResultType,
       TypeApplication_AtEnclosingClass = receiver.Type.TypeArgs,
@@ -775,7 +775,7 @@ public static Expression WrapResolvedCall(FunctionCallExpr call, SystemModuleMan
     };
 
     subst = TypeParameter.SubstitutionMap(call.Function.TypeArgs, call.TypeApplication_JustFunction);
-    return new ApplySuffix(call.tok, null, exprDotName, new ActualBindings(call.Args).ArgumentBindings, call.tok) {
+    return new ApplySuffix(call.tok, null, exprDotName, new ActualBindings(call.Args).ArgumentBindings, Token.NoToken) {
       ResolvedExpression = call,
       Type = call.Function.ResultType.Subst(subst)
     };
@@ -882,9 +882,9 @@ public static Expression CreateQuantifier(QuantifierExpr expr, bool forall, Expr
 
     QuantifierExpr q;
     if (forall) {
-      q = new ForallExpr(expr.tok, expr.RangeToken, newVars, expr.Range, body, expr.Attributes);
+      q = new ForallExpr(expr.tok, expr.Origin, newVars, expr.Range, body, expr.Attributes);
     } else {
-      q = new ExistsExpr(expr.tok, expr.RangeToken, newVars, expr.Range, body, expr.Attributes);
+      q = new ExistsExpr(expr.tok, expr.Origin, newVars, expr.Range, body, expr.Attributes);
     }
     q.Type = Type.Bool;
 
diff --git a/Source/DafnyCore/AST/Expressions/Heap/FrameExpression.cs b/Source/DafnyCore/AST/Expressions/Heap/FrameExpression.cs
index 5e9764e5f1d..cab4106d4d5 100644
--- a/Source/DafnyCore/AST/Expressions/Heap/FrameExpression.cs
+++ b/Source/DafnyCore/AST/Expressions/Heap/FrameExpression.cs
@@ -36,7 +36,7 @@ public FrameExpression(IOrigin tok, Expression e, string fieldName) {
   }
 
   public FrameExpression(Cloner cloner, FrameExpression original) {
-    this.tok = cloner.Tok(original.tok);
+    this.tok = cloner.Origin(original.tok);
     OriginalExpression = cloner.CloneExpr(original.OriginalExpression);
     FieldName = original.FieldName;
 
diff --git a/Source/DafnyCore/AST/Expressions/Operators/ChainingExpression.cs b/Source/DafnyCore/AST/Expressions/Operators/ChainingExpression.cs
index 16c4577637e..86bb48e2b24 100644
--- a/Source/DafnyCore/AST/Expressions/Operators/ChainingExpression.cs
+++ b/Source/DafnyCore/AST/Expressions/Operators/ChainingExpression.cs
@@ -19,12 +19,13 @@ public ChainingExpression Clone(Cloner cloner) {
   public ChainingExpression(Cloner cloner, ChainingExpression original) : base(cloner, original) {
     Operands = original.Operands.Select(cloner.CloneExpr).ToList();
     Operators = original.Operators;
-    OperatorLocs = original.OperatorLocs.Select(cloner.Tok).ToList();
+    OperatorLocs = original.OperatorLocs.Select(cloner.Origin).ToList();
     PrefixLimits = original.PrefixLimits.Select(cloner.CloneExpr).ToList();
     E = ComputeDesugaring(Operands, Operators, OperatorLocs, PrefixLimits);
   }
 
-  public ChainingExpression(IOrigin tok, List<Expression> operands, List<BinaryExpr.Opcode> operators, List<IOrigin> operatorLocs, List<Expression/*?*/> prefixLimits)
+  public ChainingExpression(IOrigin tok, List<Expression> operands, List<BinaryExpr.Opcode> operators,
+    List<IOrigin> operatorLocs, List<Expression/*?*/> prefixLimits)
     : base(tok) {
     Contract.Requires(tok != null);
     Contract.Requires(operands != null);
diff --git a/Source/DafnyCore/AST/Expressions/Variables/BoundVar.cs b/Source/DafnyCore/AST/Expressions/Variables/BoundVar.cs
index 6a7b0083b73..9c81fb52794 100644
--- a/Source/DafnyCore/AST/Expressions/Variables/BoundVar.cs
+++ b/Source/DafnyCore/AST/Expressions/Variables/BoundVar.cs
@@ -85,15 +85,21 @@ public IEnumerable<BoundVar> AllBoundVars {
 class QuantifiedVariableDomainCloner : Cloner {
   public static readonly QuantifiedVariableDomainCloner Instance = new QuantifiedVariableDomainCloner();
   private QuantifiedVariableDomainCloner() { }
-  public override IOrigin Tok(IOrigin tok) {
-    return new QuantifiedVariableDomainOrigin(tok);
+  public override IOrigin Origin(IOrigin origin) {
+    if (origin == null) {
+      return null;
+    }
+    return new QuantifiedVariableDomainOrigin(origin);
   }
 }
 
 class QuantifiedVariableRangeCloner : Cloner {
   public static readonly QuantifiedVariableRangeCloner Instance = new QuantifiedVariableRangeCloner();
   private QuantifiedVariableRangeCloner() { }
-  public override IOrigin Tok(IOrigin tok) {
-    return new QuantifiedVariableRangeOrigin(tok);
+  public override IOrigin Origin(IOrigin origin) {
+    if (origin == null) {
+      return null;
+    }
+    return new QuantifiedVariableRangeOrigin(origin);
   }
 }
\ No newline at end of file
diff --git a/Source/DafnyCore/AST/Expressions/Variables/CasePattern.cs b/Source/DafnyCore/AST/Expressions/Variables/CasePattern.cs
index 6cde690cf23..363e70ed88f 100644
--- a/Source/DafnyCore/AST/Expressions/Variables/CasePattern.cs
+++ b/Source/DafnyCore/AST/Expressions/Variables/CasePattern.cs
@@ -30,7 +30,7 @@ public void MakeAConstructor() {
   }
 
   public CasePattern(Cloner cloner, CasePattern<VT> original) {
-    tok = cloner.Tok(original.tok);
+    tok = cloner.Origin(original.tok);
     Id = original.Id;
     if (original.Var != null) {
       Var = cloner.CloneIVariable(original.Var, false);
diff --git a/Source/DafnyCore/AST/Expressions/Variables/IdentifierExpr.cs b/Source/DafnyCore/AST/Expressions/Variables/IdentifierExpr.cs
index 8c4e511da5c..5b195dc1b10 100644
--- a/Source/DafnyCore/AST/Expressions/Variables/IdentifierExpr.cs
+++ b/Source/DafnyCore/AST/Expressions/Variables/IdentifierExpr.cs
@@ -13,7 +13,7 @@ void ObjectInvariant() {
   public readonly string Name;
   [FilledInDuringResolution] public IVariable Var;
 
-  public string DafnyName => tok.line > 0 ? RangeToken.PrintOriginal() : Name;
+  public string DafnyName => tok.line > 0 ? Origin.PrintOriginal() : Name;
 
   public IdentifierExpr(IOrigin tok, string name)
     : base(tok) {
diff --git a/Source/DafnyCore/AST/Expressions/Variables/NonglobalVariable.cs b/Source/DafnyCore/AST/Expressions/Variables/NonglobalVariable.cs
index 4ad78a05a4b..57c73519350 100644
--- a/Source/DafnyCore/AST/Expressions/Variables/NonglobalVariable.cs
+++ b/Source/DafnyCore/AST/Expressions/Variables/NonglobalVariable.cs
@@ -31,7 +31,7 @@ public string Name {
       return name;
     }
   }
-  public string DafnyName => RangeToken == null || tok.line == 0 ? Name : RangeToken.PrintOriginal();
+  public string DafnyName => Origin == null || tok.line == 0 ? Name : Origin.PrintOriginal();
   public string DisplayName =>
     LocalVariable.DisplayNameHelper(this);
 
@@ -136,7 +136,7 @@ public void MakeGhost() {
     IsGhost = true;
   }
 
-  public IOrigin NavigationToken => tok;
+  public IOrigin NavigationToken => Center;
   public override IEnumerable<INode> Children => IsTypeExplicit ? new List<Node> { Type } : Enumerable.Empty<Node>();
   public override IEnumerable<INode> PreResolveChildren => IsTypeExplicit ? new List<Node>() { Type } : Enumerable.Empty<Node>();
   public SymbolKind? Kind => SymbolKind.Variable;
diff --git a/Source/DafnyCore/AST/ExtremeCloner.cs b/Source/DafnyCore/AST/ExtremeCloner.cs
index c5d24c32921..b6d119f2ec5 100644
--- a/Source/DafnyCore/AST/ExtremeCloner.cs
+++ b/Source/DafnyCore/AST/ExtremeCloner.cs
@@ -31,18 +31,18 @@ protected Expression CloneCallAndAddK(ApplySuffix e) {
     string name;
     if (e.Lhs is NameSegment ns) {
       name = ns.Name;
-      lhs = new NameSegment(Tok(ns.tok), name + "#", ns.OptTypeArguments?.ConvertAll(CloneType));
+      lhs = new NameSegment(Origin(ns.tok), name + "#", ns.OptTypeArguments?.ConvertAll(CloneType));
     } else {
       var edn = (ExprDotName)e.Lhs;
       name = edn.SuffixName;
-      lhs = new ExprDotName(Tok(edn.tok), CloneExpr(edn.Lhs), name + "#", edn.OptTypeArguments?.ConvertAll(CloneType));
+      lhs = new ExprDotName(Origin(edn.tok), CloneExpr(edn.Lhs), name + "#", edn.OptTypeArguments?.ConvertAll(CloneType));
     }
     var args = new List<ActualBinding>();
     args.Add(new ActualBinding(null, k));
     foreach (var arg in e.Bindings.ArgumentBindings) {
       args.Add(CloneActualBinding(arg));
     }
-    var apply = new ApplySuffix(Tok(e.tok), e.AtTok == null ? null : Tok(e.AtTok), lhs, args, Tok(e.CloseParen));
+    var apply = new ApplySuffix(Origin(e.tok), e.AtTok == null ? null : Origin(e.AtTok), lhs, args, e.CloseParen);
     reporter.Info(MessageSource.Cloner, e.tok, name + suffix);
     return apply;
   }
@@ -59,7 +59,7 @@ protected Expression CloneCallAndAddK(FunctionCallExpr e) {
     foreach (var binding in e.Bindings.ArgumentBindings) {
       args.Add(CloneActualBinding(binding));
     }
-    var fexp = new FunctionCallExpr(Tok(e.tok), e.Name + "#", receiver, e.OpenParen, e.CloseParen, args, e.AtLabel);
+    var fexp = new FunctionCallExpr(Origin(e.tok), e.Name + "#", receiver, e.OpenParen, e.CloseParen, args, e.AtLabel);
     reporter.Info(MessageSource.Cloner, e.tok, e.Name + suffix);
     return fexp;
   }
@@ -69,7 +69,7 @@ protected Expression CloneEqualityAndAddK(BinaryExpr binaryExpr) {
       throw new NotImplementedException();
     }
 
-    var eq = new TernaryExpr(Tok(binaryExpr.tok),
+    var eq = new TernaryExpr(Origin(binaryExpr.tok),
       binaryExpr.ResolvedOp == BinaryExpr.ResolvedOpcode.EqCommon ? TernaryExpr.Opcode.PrefixEqOp : TernaryExpr.Opcode.PrefixNeqOp,
       k, CloneExpr(binaryExpr.E0), CloneExpr(binaryExpr.E1));
     reporter.Info(MessageSource.Cloner, binaryExpr.tok, "==" + suffix);
diff --git a/Source/DafnyCore/AST/ExtremeLemmaBodyCloner.cs b/Source/DafnyCore/AST/ExtremeLemmaBodyCloner.cs
index 98a3033e6d6..98824b613a2 100644
--- a/Source/DafnyCore/AST/ExtremeLemmaBodyCloner.cs
+++ b/Source/DafnyCore/AST/ExtremeLemmaBodyCloner.cs
@@ -34,7 +34,7 @@ public override Expression CloneExpr(Expression expr) {
           return CloneCallAndAddK(functionCallExpr);
         }
       } else if (expr is StaticReceiverExpr ee) {
-        return new StaticReceiverExpr(Tok(ee.tok), ee.Type, ee.IsImplicit);
+        return new StaticReceiverExpr(Origin(ee.tok), ee.Type, ee.IsImplicit);
       } else if (expr is ApplySuffix apply) {
         if (!apply.WasResolved()) {
           // Since we're assuming the enclosing statement to have been resolved, this ApplySuffix must
@@ -66,17 +66,17 @@ public override AssignmentRhs CloneRHS(AssignmentRhs rhs) {
         Expression lhsClone;
         if (apply.Lhs is NameSegment) {
           var lhs = (NameSegment)apply.Lhs;
-          lhsClone = new NameSegment(Tok(lhs.tok), lhs.Name + "#", lhs.OptTypeArguments?.ConvertAll(CloneType));
+          lhsClone = new NameSegment(Origin(lhs.tok), lhs.Name + "#", lhs.OptTypeArguments?.ConvertAll(CloneType));
         } else {
           var lhs = (ExprDotName)apply.Lhs;
-          lhsClone = new ExprDotName(Tok(lhs.tok), CloneExpr(lhs.Lhs), lhs.SuffixName + "#", lhs.OptTypeArguments?.ConvertAll(CloneType));
+          lhsClone = new ExprDotName(Origin(lhs.tok), CloneExpr(lhs.Lhs), lhs.SuffixName + "#", lhs.OptTypeArguments?.ConvertAll(CloneType));
         }
 
         var args = new List<ActualBinding>();
         args.Add(new ActualBinding(null, k));
         apply.Bindings.ArgumentBindings.ForEach(arg => args.Add(CloneActualBinding(arg)));
-        var applyClone = new ApplySuffix(Tok(apply.tok), apply.AtTok == null ? null : Tok(apply.AtTok),
-          lhsClone, args, Tok(apply.CloseParen));
+        var applyClone = new ApplySuffix(Origin(apply.tok), apply.AtTok == null ? null : Origin(apply.AtTok),
+          lhsClone, args, apply.CloseParen);
         var c = new ExprRhs(applyClone, CloneAttributes(rhs.Attributes));
         reporter.Info(MessageSource.Cloner, apply.Lhs.tok, extremeLemma.Name + suffix);
         return c;
diff --git a/Source/DafnyCore/AST/ExtremeLemmaSpecificationSubstituter.cs b/Source/DafnyCore/AST/ExtremeLemmaSpecificationSubstituter.cs
index 0ffa7e0b7aa..9155165e8d9 100644
--- a/Source/DafnyCore/AST/ExtremeLemmaSpecificationSubstituter.cs
+++ b/Source/DafnyCore/AST/ExtremeLemmaSpecificationSubstituter.cs
@@ -53,7 +53,7 @@ public override Expression CloneExpr(Expression expr) {
         var op = e.ResolvedOp == BinaryExpr.ResolvedOpcode.EqCommon ? TernaryExpr.Opcode.PrefixEqOp : TernaryExpr.Opcode.PrefixNeqOp;
         var A = CloneExpr(e.E0);
         var B = CloneExpr(e.E1);
-        var teq = new TernaryExpr(Tok(e.tok), op, k, A, B);
+        var teq = new TernaryExpr(Origin(e.tok), op, k, A, B);
         var opString = op == TernaryExpr.Opcode.PrefixEqOp ? "==" : "!=";
         reporter.Info(MessageSource.Cloner, e.tok, opString + suffix);
         return teq;
@@ -66,7 +66,7 @@ public override Type CloneType(Type t) {
       var tt = (UserDefinedType)t;
       // We want syntactic cloning of the Expression that is tt.NamePath, unlike the semantic (that is, post-resolved)
       // cloning that CloneExpr is doing above.
-      return new UserDefinedType(Tok(tt.tok), CloneNamePathExpression(tt.NamePath));
+      return new UserDefinedType(Origin(tt.tok), CloneNamePathExpression(tt.NamePath));
     } else {
       return base.CloneType(t);
     }
@@ -78,7 +78,7 @@ Expression CloneNamePathExpression(Expression expr) {
       return new NameSegment(this, e);
     } else {
       var e = (ExprDotName)expr;
-      return new ExprDotName(Tok(e.tok), CloneNamePathExpression(e.Lhs), e.SuffixName, e.OptTypeArguments == null ? null : e.OptTypeArguments.ConvertAll(CloneType));
+      return new ExprDotName(Origin(e.tok), CloneNamePathExpression(e.Lhs), e.SuffixName, e.OptTypeArguments == null ? null : e.OptTypeArguments.ConvertAll(CloneType));
     }
   }
 }
diff --git a/Source/DafnyCore/AST/Grammar/ParseErrors.cs b/Source/DafnyCore/AST/Grammar/ParseErrors.cs
index ecebdd4dbc6..48d58d93e50 100644
--- a/Source/DafnyCore/AST/Grammar/ParseErrors.cs
+++ b/Source/DafnyCore/AST/Grammar/ParseErrors.cs
@@ -457,7 +457,7 @@ state properties of the otherwise uninterpreted or abstract type.
 ".TrimStart(), range =>
     range.Prev.val == "," ?
       new List<DafnyAction> {
-      OneAction("remove comma", range.Prev.ToRange(), ""),
+      OneAction("remove comma", range.Prev.SingleTokenRange(), ""),
       OneAction("insert '=='", range, "==" + range.PrintOriginal()),
       OneAction("insert '0'", range, "0" + range.PrintOriginal()),
       OneAction("insert '00'", range, "00" + range.PrintOriginal()),
diff --git a/Source/DafnyCore/AST/Grammar/ParserNonGeneratedPart.cs b/Source/DafnyCore/AST/Grammar/ParserNonGeneratedPart.cs
index 78b8e530467..cf9683cb673 100644
--- a/Source/DafnyCore/AST/Grammar/ParserNonGeneratedPart.cs
+++ b/Source/DafnyCore/AST/Grammar/ParserNonGeneratedPart.cs
@@ -17,9 +17,9 @@ public Parser(DafnyOptions options, Scanner/*!*/ scanner, Errors/*!*/ errors, Ca
     dummyExpr = new LiteralExpr(Token.NoToken);
     dummyRhs = new ExprRhs(dummyExpr);
     dummyFrameExpr = new FrameExpression(dummyExpr.tok, dummyExpr, null);
-    dummyStmt = new ReturnStmt(Token.NoToken.ToRange(), null);
-    var dummyBlockStmt = new BlockStmt(Token.NoToken.ToRange(), new List<Statement>());
-    dummyIfStmt = new IfStmt(Token.NoToken.ToRange(), false, null, dummyBlockStmt, null);
+    dummyStmt = new ReturnStmt(Token.NoToken, null);
+    var dummyBlockStmt = new BlockStmt(Token.NoToken, new List<Statement>());
+    dummyIfStmt = new IfStmt(Token.NoToken, false, null, dummyBlockStmt, null);
 
     theOptions = new DafnyOptions(options);
     theModule = new FileModuleDefinition(scanner.FirstToken);
@@ -660,21 +660,21 @@ int StringToInt(string s, int defaultValue, string errString, IOrigin tok) {
   /// </summary>
   class DeclModifierData {
     public bool IsReplaceable;
-    public IOrigin ReplaceableToken;
+    public Token ReplaceableToken;
     public bool IsAbstract;
-    public IOrigin AbstractToken;
+    public Token AbstractToken;
     public bool IsGhost;
-    public IOrigin GhostToken;
+    public Token GhostToken;
     public bool IsStatic;
-    public IOrigin StaticToken;
+    public Token StaticToken;
     public bool IsOpaque;
-    public IOrigin OpaqueToken;
-    public IOrigin FirstTokenExceptAttributes;
+    public Token OpaqueToken;
+    public Token FirstTokenExceptAttributes;
     public Attributes Attributes = null;
 
-    public IOrigin FirstToken {
+    public Token FirstToken {
       get {
-        IOrigin result = FirstTokenExceptAttributes;
+        Token result = FirstTokenExceptAttributes;
         foreach (var attr in Attributes.AsEnumerable()) {
           if (result == null || result.pos > attr.tok.pos) {
             result = attr.StartToken;
@@ -706,13 +706,13 @@ private ModuleKindEnum GetModuleKind(DeclModifierData mods) {
   /// </summary>
   public void CheckNoAttributes(ref Attributes attrs) {
     if (attrs != null) {
-      SemErr(ErrorId.p_extra_attributes, attrs.RangeToken, "Attribute not expected here");
+      SemErr(ErrorId.p_extra_attributes, attrs.Origin, "Attribute not expected here");
       attrs = null;
     }
   }
 
   // Check that token has not been set, then set it.
-  public void CheckAndSetToken(ref IOrigin token) {
+  public void CheckAndSetToken(ref Token token) {
     if (token != null) {
       SemErr(ErrorId.p_duplicate_modifier, t, "Duplicate declaration modifier: " + t.val);
     }
@@ -720,7 +720,7 @@ public void CheckAndSetToken(ref IOrigin token) {
   }
 
   // Check that token has not been set, then set it, but just ignores if it was set already
-  public void CheckAndSetTokenOnce(ref IOrigin token) {
+  public void CheckAndSetTokenOnce(ref Token token) {
     if (token == null) {
       token = t;
     }
diff --git a/Source/DafnyCore/AST/Grammar/TokenNewIndentCollector.cs b/Source/DafnyCore/AST/Grammar/TokenNewIndentCollector.cs
index d8053a4f69a..aaa282f5a14 100644
--- a/Source/DafnyCore/AST/Grammar/TokenNewIndentCollector.cs
+++ b/Source/DafnyCore/AST/Grammar/TokenNewIndentCollector.cs
@@ -650,7 +650,7 @@ void InferRightIndentFromRhs() {
         return;
       }
 
-      rightIndent = GetNewTokenVisualIndent(rhs.RangeToken.StartToken, rightIndent);
+      rightIndent = GetNewTokenVisualIndent(rhs.Origin.StartToken, rightIndent);
     }
 
     if (!ownedTokens.Any(token => token.val == ":=" || token.val == ":-" || token.val == ":|")) {
diff --git a/Source/DafnyCore/AST/IHasReferences.cs b/Source/DafnyCore/AST/IHasReferences.cs
index a402207c88c..c1c545efac4 100644
--- a/Source/DafnyCore/AST/IHasReferences.cs
+++ b/Source/DafnyCore/AST/IHasReferences.cs
@@ -9,6 +9,10 @@ namespace Microsoft.Dafny;
 /// Node that has a token that is used to navigate to this node
 /// </summary>
 public interface IHasNavigationToken : INode {
+  /// <summary>
+  /// For declarations, we could point to a Name,
+  /// but for references we can not, so we return an origin 
+  /// </summary>
   IOrigin NavigationToken { get; }
 }
 
diff --git a/Source/DafnyCore/AST/IOrigin.cs b/Source/DafnyCore/AST/IOrigin.cs
index 271189a53c8..d3761694927 100644
--- a/Source/DafnyCore/AST/IOrigin.cs
+++ b/Source/DafnyCore/AST/IOrigin.cs
@@ -4,8 +4,15 @@
 namespace Microsoft.Dafny;
 
 public interface IOrigin : Microsoft.Boogie.IToken, IComparable<IOrigin> {
-  public RangeToken To(IOrigin end) => new RangeToken(this, end);
 
+  public bool InclusiveEnd => EndToken != null;
+
+  bool IsMissingRange { get; }
+  bool IsInherited(ModuleDefinition d);
+  Token Center { get; }
+  Token StartToken { get; }
+  Token EndToken { get; }
+  public bool ContainsRange { get; }
   /*
   int kind { get; set; }
   int pos { get; set; }
@@ -18,8 +25,8 @@ string Boogie.IToken.filename {
     set => throw new NotSupportedException();
   }
 
-  public string ActualFilename => Uri.LocalPath;
-  string Filepath => Uri.LocalPath;
+  public string ActualFilename => Uri?.LocalPath;
+  string Filepath => Uri?.LocalPath;
 
   Uri Uri { get; set; }
 
diff --git a/Source/DafnyCore/AST/Members/ConstantField.cs b/Source/DafnyCore/AST/Members/ConstantField.cs
index 8506590ef68..afe41fd4d78 100644
--- a/Source/DafnyCore/AST/Members/ConstantField.cs
+++ b/Source/DafnyCore/AST/Members/ConstantField.cs
@@ -12,7 +12,7 @@ public class ConstantField : SpecialField, ICallable, ICanAutoRevealDependencies
 
   public override bool IsOpaque { get; }
 
-  public ConstantField(RangeToken rangeOrigin, Name name, Expression/*?*/ rhs, bool hasStaticKeyword, bool isGhost, bool isOpaque, Type type, Attributes attributes)
+  public ConstantField(IOrigin rangeOrigin, Name name, Expression/*?*/ rhs, bool hasStaticKeyword, bool isGhost, bool isOpaque, Type type, Attributes attributes)
     : base(rangeOrigin, name, ID.UseIdParam, NonglobalVariable.SanitizeName(name.Value), hasStaticKeyword, isGhost, false, false, type, attributes) {
     Contract.Requires(tok != null);
     Contract.Requires(name != null);
diff --git a/Source/DafnyCore/AST/Members/Constructor.cs b/Source/DafnyCore/AST/Members/Constructor.cs
index fcdefd4b986..626951606fc 100644
--- a/Source/DafnyCore/AST/Members/Constructor.cs
+++ b/Source/DafnyCore/AST/Members/Constructor.cs
@@ -34,7 +34,7 @@ public List<Statement> BodyProper {  // second part of Body's statements
       }
     }
   }
-  public Constructor(RangeToken rangeOrigin, Name name,
+  public Constructor(IOrigin rangeOrigin, Name name,
     bool isGhost,
     List<TypeParameter> typeArgs,
     List<Formal> ins,
diff --git a/Source/DafnyCore/AST/Members/ExtremeLemma.cs b/Source/DafnyCore/AST/Members/ExtremeLemma.cs
index 22bddc75f4d..f8324529ae5 100644
--- a/Source/DafnyCore/AST/Members/ExtremeLemma.cs
+++ b/Source/DafnyCore/AST/Members/ExtremeLemma.cs
@@ -18,7 +18,7 @@ public ExtremeLemma(Cloner cloner, ExtremeLemma lemma) : base(cloner, lemma) {
     TypeOfK = lemma.TypeOfK;
   }
 
-  public ExtremeLemma(RangeToken rangeOrigin, Name name,
+  protected ExtremeLemma(IOrigin rangeOrigin, Name name,
     bool hasStaticKeyword, ExtremePredicate.KType typeOfK,
     List<TypeParameter> typeArgs,
     List<Formal> ins, [Captured] List<Formal> outs,
@@ -48,7 +48,7 @@ public ExtremeLemma(RangeToken rangeOrigin, Name name,
 public class LeastLemma : ExtremeLemma {
   public override string WhatKind => "least lemma";
 
-  public LeastLemma(RangeToken rangeOrigin, Name name,
+  public LeastLemma(IOrigin rangeOrigin, Name name,
     bool hasStaticKeyword, ExtremePredicate.KType typeOfK,
     List<TypeParameter> typeArgs,
     List<Formal> ins, [Captured] List<Formal> outs,
@@ -78,7 +78,7 @@ public LeastLemma(Cloner cloner, LeastLemma leastLemma) : base(cloner, leastLemm
 public class GreatestLemma : ExtremeLemma {
   public override string WhatKind => "greatest lemma";
 
-  public GreatestLemma(RangeToken rangeOrigin, Name name,
+  public GreatestLemma(IOrigin rangeOrigin, Name name,
     bool hasStaticKeyword, ExtremePredicate.KType typeOfK,
     List<TypeParameter> typeArgs,
     List<Formal> ins, [Captured] List<Formal> outs,
diff --git a/Source/DafnyCore/AST/Members/ExtremePredicate.cs b/Source/DafnyCore/AST/Members/ExtremePredicate.cs
index 680be99e74a..5d7ea3f2015 100644
--- a/Source/DafnyCore/AST/Members/ExtremePredicate.cs
+++ b/Source/DafnyCore/AST/Members/ExtremePredicate.cs
@@ -19,11 +19,11 @@ public bool KNat {
   public override IEnumerable<INode> Children => base.Children.Concat(new[] { PrefixPredicate });
   public override IEnumerable<INode> PreResolveChildren => base.Children;
 
-  public ExtremePredicate(RangeToken rangeOrigin, Name name, bool hasStaticKeyword, bool isOpaque, KType typeOfK,
+  public ExtremePredicate(IOrigin rangeToken, Name name, bool hasStaticKeyword, bool isOpaque, KType typeOfK,
     List<TypeParameter> typeArgs, List<Formal> ins, Formal result,
     List<AttributedExpression> req, Specification<FrameExpression> reads, List<AttributedExpression> ens,
     Expression body, Attributes attributes, IOrigin signatureEllipsis)
-    : base(rangeOrigin, name, hasStaticKeyword, true, isOpaque, typeArgs, ins, result, Type.Bool,
+    : base(rangeToken, name, hasStaticKeyword, true, isOpaque, typeArgs, ins, result, Type.Bool,
       req, reads, ens, new Specification<Expression>(new List<Expression>(), null), body, null, null, attributes, signatureEllipsis) {
     TypeOfK = typeOfK;
   }
@@ -52,22 +52,22 @@ public FunctionCallExpr CreatePrefixPredicateCall(FunctionCallExpr fexp, Express
 
 public class GreatestPredicate : ExtremePredicate {
   public override string WhatKind => "greatest predicate";
-  public GreatestPredicate(RangeToken rangeOrigin, Name name, bool hasStaticKeyword, bool isOpaque, KType typeOfK,
+  public GreatestPredicate(IOrigin rangeToken, Name name, bool hasStaticKeyword, bool isOpaque, KType typeOfK,
     List<TypeParameter> typeArgs, List<Formal> ins, Formal result,
     List<AttributedExpression> req, Specification<FrameExpression> reads, List<AttributedExpression> ens,
     Expression body, Attributes attributes, IOrigin signatureEllipsis)
-    : base(rangeOrigin, name, hasStaticKeyword, isOpaque, typeOfK, typeArgs, ins, result,
+    : base(rangeToken, name, hasStaticKeyword, isOpaque, typeOfK, typeArgs, ins, result,
       req, reads, ens, body, attributes, signatureEllipsis) {
   }
 }
 
 public class LeastPredicate : ExtremePredicate {
   public override string WhatKind => "least predicate";
-  public LeastPredicate(RangeToken rangeOrigin, Name name, bool hasStaticKeyword, bool isOpaque, KType typeOfK,
+  public LeastPredicate(IOrigin rangeToken, Name name, bool hasStaticKeyword, bool isOpaque, KType typeOfK,
     List<TypeParameter> typeArgs, List<Formal> ins, Formal result,
     List<AttributedExpression> req, Specification<FrameExpression> reads, List<AttributedExpression> ens,
     Expression body, Attributes attributes, IOrigin signatureEllipsis)
-    : base(rangeOrigin, name, hasStaticKeyword, isOpaque, typeOfK, typeArgs, ins, result,
+    : base(rangeToken, name, hasStaticKeyword, isOpaque, typeOfK, typeArgs, ins, result,
       req, reads, ens, body, attributes, signatureEllipsis) {
   }
 }
\ No newline at end of file
diff --git a/Source/DafnyCore/AST/Members/Field.cs b/Source/DafnyCore/AST/Members/Field.cs
index ab302a10208..9656497b136 100644
--- a/Source/DafnyCore/AST/Members/Field.cs
+++ b/Source/DafnyCore/AST/Members/Field.cs
@@ -21,14 +21,14 @@ void ObjectInvariant() {
   public override IEnumerable<INode> Children =>
     (Type?.Nodes ?? Enumerable.Empty<INode>()).Concat(this.Attributes.AsEnumerable());
 
-  public Field(RangeToken rangeOrigin, Name name, bool isGhost, Type type, Attributes attributes)
+  public Field(IOrigin rangeOrigin, Name name, bool isGhost, Type type, Attributes attributes)
     : this(rangeOrigin, name, false, isGhost, true, true, type, attributes) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(name != null);
     Contract.Requires(type != null);
   }
 
-  public Field(RangeToken rangeOrigin, Name name, bool hasStaticKeyword, bool isGhost, bool isMutable, bool isUserMutable, Type type, Attributes attributes)
+  public Field(IOrigin rangeOrigin, Name name, bool hasStaticKeyword, bool isGhost, bool isMutable, bool isUserMutable, Type type, Attributes attributes)
     : base(rangeOrigin, name, hasStaticKeyword, isGhost, attributes, false) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(name != null);
diff --git a/Source/DafnyCore/AST/Members/Function.cs b/Source/DafnyCore/AST/Members/Function.cs
index dcf4ba2a92a..e8d28c3d55d 100644
--- a/Source/DafnyCore/AST/Members/Function.cs
+++ b/Source/DafnyCore/AST/Members/Function.cs
@@ -227,7 +227,7 @@ void ObjectInvariant() {
     Contract.Invariant(Decreases != null);
   }
 
-  public Function(RangeToken range, Name name, bool hasStaticKeyword, bool isGhost, bool isOpaque,
+  public Function(IOrigin range, Name name, bool hasStaticKeyword, bool isGhost, bool isOpaque,
     List<TypeParameter> typeArgs, List<Formal> ins, Formal result, Type resultType,
     List<AttributedExpression> req, Specification<FrameExpression> reads, List<AttributedExpression> ens, Specification<Expression> decreases,
     Expression/*?*/ body, IOrigin/*?*/ byMethodTok, BlockStmt/*?*/ byMethodBody,
@@ -581,7 +581,7 @@ public void AutoRevealDependencies(AutoRevealFunctionDependencies rewriter, Dafn
       Body = bodyExpr;
 
       if (Req.Any() || Ens.Any()) {
-        Req.Insert(0, new AttributedExpression(reqExpr));
+        Req.Insert(0, new AttributedExpression(reqExpr.Origin, reqExpr));
       }
     }
 
diff --git a/Source/DafnyCore/AST/Members/ICodeContext.cs b/Source/DafnyCore/AST/Members/ICodeContext.cs
index 2f711c6e840..72a326b4d6c 100644
--- a/Source/DafnyCore/AST/Members/ICodeContext.cs
+++ b/Source/DafnyCore/AST/Members/ICodeContext.cs
@@ -103,8 +103,14 @@ public bool InferredDecreases {
   public bool AllowsAllocation => CwInner.AllowsAllocation;
 
   public bool SingleFileToken => CwInner.SingleFileToken;
+  public Token Center => CwInner.Center;
   public IEnumerable<IOrigin> OwnedTokens => CwInner.OwnedTokens;
-  public RangeToken RangeToken => CwInner.RangeToken;
+  public IOrigin Origin => CwInner.Origin;
+
+  public IOrigin RangeOrigin {
+    set => CwInner.RangeOrigin = value;
+  }
+
   public IOrigin NavigationToken => CwInner.NavigationToken;
   public SymbolKind? Kind => CwInner.Kind;
   public string GetDescription(DafnyOptions options) {
diff --git a/Source/DafnyCore/AST/Members/Lemma.cs b/Source/DafnyCore/AST/Members/Lemma.cs
index f0907852c60..df4d2aa3a73 100644
--- a/Source/DafnyCore/AST/Members/Lemma.cs
+++ b/Source/DafnyCore/AST/Members/Lemma.cs
@@ -6,7 +6,7 @@ namespace Microsoft.Dafny;
 public class Lemma : Method {
   public override string WhatKind => "lemma";
   public override string WhatKindMentionGhost => WhatKind;
-  public Lemma(RangeToken rangeOrigin, Name name,
+  public Lemma(IOrigin rangeOrigin, Name name,
     bool hasStaticKeyword,
     [Captured] List<TypeParameter> typeArgs,
     [Captured] List<Formal> ins, [Captured] List<Formal> outs,
@@ -30,7 +30,7 @@ public class TwoStateLemma : Method {
   public override string WhatKind => "twostate lemma";
   public override string WhatKindMentionGhost => WhatKind;
 
-  public TwoStateLemma(RangeToken rangeOrigin, Name name,
+  public TwoStateLemma(IOrigin rangeOrigin, Name name,
     bool hasStaticKeyword,
     [Captured] List<TypeParameter> typeArgs,
     [Captured] List<Formal> ins, [Captured] List<Formal> outs,
diff --git a/Source/DafnyCore/AST/Members/MemberDecl.cs b/Source/DafnyCore/AST/Members/MemberDecl.cs
index a8c93fe879b..fbea09c09c6 100644
--- a/Source/DafnyCore/AST/Members/MemberDecl.cs
+++ b/Source/DafnyCore/AST/Members/MemberDecl.cs
@@ -67,7 +67,7 @@ protected MemberDecl(Cloner cloner, MemberDecl original) : base(cloner, original
     this.isGhost = original.isGhost;
   }
 
-  protected MemberDecl(RangeToken rangeOrigin, Name name, bool hasStaticKeyword, bool isGhost, Attributes attributes, bool isRefining)
+  protected MemberDecl(IOrigin rangeOrigin, Name name, bool hasStaticKeyword, bool isGhost, Attributes attributes, bool isRefining)
     : base(rangeOrigin, name, attributes, isRefining) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(name != null);
diff --git a/Source/DafnyCore/AST/Members/Method.cs b/Source/DafnyCore/AST/Members/Method.cs
index 75704e519ba..d4215043f86 100644
--- a/Source/DafnyCore/AST/Members/Method.cs
+++ b/Source/DafnyCore/AST/Members/Method.cs
@@ -131,7 +131,7 @@ public Method(Cloner cloner, Method original) : base(cloner, original) {
     this.IsByMethod = original.IsByMethod;
   }
 
-  public Method(RangeToken rangeOrigin, Name name,
+  public Method(IOrigin rangeOrigin, Name name,
     bool hasStaticKeyword, bool isGhost,
     [Captured] List<TypeParameter> typeArgs,
     [Captured] List<Formal> ins, [Captured] List<Formal> outs,
@@ -498,7 +498,7 @@ public void AutoRevealDependencies(AutoRevealFunctionDependencies Rewriter, Dafn
       }
 
       if (Req.Any() || Ens.Any()) {
-        Req.Insert(0, new AttributedExpression(reqExpr));
+        Req.Insert(0, new AttributedExpression(reqExpr.Origin, reqExpr));
       }
     }
 
diff --git a/Source/DafnyCore/AST/Members/MethodOrFunction.cs b/Source/DafnyCore/AST/Members/MethodOrFunction.cs
index 30b0b27ae94..4c8013dd075 100644
--- a/Source/DafnyCore/AST/Members/MethodOrFunction.cs
+++ b/Source/DafnyCore/AST/Members/MethodOrFunction.cs
@@ -22,7 +22,7 @@ static MethodOrFunction() {
   public readonly Specification<Expression> Decreases;
   public readonly List<Formal> Ins;
 
-  protected MethodOrFunction(RangeToken rangeOrigin, Name name, bool hasStaticKeyword, bool isGhost,
+  protected MethodOrFunction(IOrigin rangeOrigin, Name name, bool hasStaticKeyword, bool isGhost,
     Attributes attributes, bool isRefining, List<TypeParameter> typeArgs, List<Formal> ins,
     List<AttributedExpression> req,
     List<AttributedExpression> ens,
@@ -74,11 +74,11 @@ public void ResolveMethodOrFunction(INewOrOldResolver resolver) {
         $"Dafny can not guarantee that it is called with arguments that satisfy its preconditions (its requires clauses and inputs that are subset types). " +
         $"To silence this warning, please add an {{:axiom}} attribute or use the option '--allow-external-contracts'");
     }
-    if (!AutoGeneratedOrigin.Is(RangeToken) && HasVerifyFalseAttribute) {
+    if (!AutoGeneratedOrigin.Is(Origin) && HasVerifyFalseAttribute) {
       resolver.Reporter.Warning(MessageSource.Verifier, ResolutionErrors.ErrorId.none, Tok,
         $"The {{:verify false}} attribute should only be used during development. " +
         $"Consider using a bodyless {WhatKind} together with the {{:axiom}} attribute instead");
-    } else if (!AutoGeneratedOrigin.Is(RangeToken) && Bodyless && !IsVirtual && !IsAbstract
+    } else if (!AutoGeneratedOrigin.Is(Origin) && Bodyless && !IsVirtual && !IsAbstract
                  && !this.IsExtern(resolver.Options) && !this.IsExplicitAxiom()) {
       foreach (var ensures in Ens) {
         if (!ensures.IsExplicitAxiom() && !resolver.Options.Get(CommonOptionBag.AllowAxioms)) {
diff --git a/Source/DafnyCore/AST/Members/Predicate.cs b/Source/DafnyCore/AST/Members/Predicate.cs
index 69c272ce2c3..670847896c9 100644
--- a/Source/DafnyCore/AST/Members/Predicate.cs
+++ b/Source/DafnyCore/AST/Members/Predicate.cs
@@ -11,12 +11,12 @@ public enum BodyOriginKind {
     Extension  // this predicate extends the definition of a predicate with a body in a module being refined
   }
   public readonly BodyOriginKind BodyOrigin;
-  public Predicate(RangeToken rangeOrigin, Name name, bool hasStaticKeyword, bool isGhost, bool isOpaque,
+  public Predicate(IOrigin rangeToken, Name name, bool hasStaticKeyword, bool isGhost, bool isOpaque,
     List<TypeParameter> typeArgs, List<Formal> ins,
     Formal result,
     List<AttributedExpression> req, Specification<FrameExpression> reads, List<AttributedExpression> ens, Specification<Expression> decreases,
     Expression body, BodyOriginKind bodyOrigin, IOrigin/*?*/ byMethodTok, BlockStmt/*?*/ byMethodBody, Attributes attributes, IOrigin signatureEllipsis)
-    : base(rangeOrigin, name, hasStaticKeyword, isGhost, isOpaque, typeArgs, ins, result, Type.Bool, req, reads, ens, decreases, body, byMethodTok, byMethodBody, attributes, signatureEllipsis) {
+    : base(rangeToken, name, hasStaticKeyword, isGhost, isOpaque, typeArgs, ins, result, Type.Bool, req, reads, ens, decreases, body, byMethodTok, byMethodBody, attributes, signatureEllipsis) {
     Contract.Requires(bodyOrigin == Predicate.BodyOriginKind.OriginalOrInherited || body != null);
     BodyOrigin = bodyOrigin;
   }
diff --git a/Source/DafnyCore/AST/Members/PrefixLemma.cs b/Source/DafnyCore/AST/Members/PrefixLemma.cs
index 77bb526c5e9..c3a415b0fb2 100644
--- a/Source/DafnyCore/AST/Members/PrefixLemma.cs
+++ b/Source/DafnyCore/AST/Members/PrefixLemma.cs
@@ -12,7 +12,7 @@ public class PrefixLemma : Method {
 
   public readonly Formal K;
   public readonly ExtremeLemma ExtremeLemma;
-  public PrefixLemma(RangeToken rangeOrigin, Name name, bool hasStaticKeyword,
+  public PrefixLemma(IOrigin rangeOrigin, Name name, bool hasStaticKeyword,
     List<TypeParameter> typeArgs, Formal k, List<Formal> ins, List<Formal> outs,
     List<AttributedExpression> req, [Captured] Specification<FrameExpression> reads,
     Specification<FrameExpression> mod, List<AttributedExpression> ens, Specification<Expression> decreases,
diff --git a/Source/DafnyCore/AST/Members/PrefixPredicate.cs b/Source/DafnyCore/AST/Members/PrefixPredicate.cs
index 9ad247bd19b..bc6a7662d3b 100644
--- a/Source/DafnyCore/AST/Members/PrefixPredicate.cs
+++ b/Source/DafnyCore/AST/Members/PrefixPredicate.cs
@@ -11,11 +11,11 @@ public class PrefixPredicate : Function {
   public override string WhatKindMentionGhost => WhatKind;
   public readonly Formal K;
   public readonly ExtremePredicate ExtremePred;
-  public PrefixPredicate(RangeToken rangeOrigin, Name name, bool hasStaticKeyword,
+  public PrefixPredicate(IOrigin rangeToken, Name name, bool hasStaticKeyword,
     List<TypeParameter> typeArgs, Formal k, List<Formal> ins,
     List<AttributedExpression> req, Specification<FrameExpression> reads, List<AttributedExpression> ens, Specification<Expression> decreases,
     Expression body, Attributes attributes, ExtremePredicate extremePred)
-    : base(rangeOrigin, name, hasStaticKeyword, true, false, typeArgs, ins, null, Type.Bool, req, reads, ens, decreases, body, null, null, attributes, null) {
+    : base(rangeToken, name, hasStaticKeyword, true, false, typeArgs, ins, null, Type.Bool, req, reads, ens, decreases, body, null, null, attributes, null) {
     Contract.Requires(k != null);
     Contract.Requires(extremePred != null);
     Contract.Requires(ins != null && 1 <= ins.Count && ins[0] == k);
diff --git a/Source/DafnyCore/AST/Members/SpecialField.cs b/Source/DafnyCore/AST/Members/SpecialField.cs
index d16232edc7f..dcd56486c69 100644
--- a/Source/DafnyCore/AST/Members/SpecialField.cs
+++ b/Source/DafnyCore/AST/Members/SpecialField.cs
@@ -23,12 +23,12 @@ public enum ID {
   public readonly ID SpecialId;
   public readonly object IdParam;
 
-  public SpecialField(RangeToken rangeOrigin, string name, ID specialId, object idParam,
+  public SpecialField(IOrigin rangeOrigin, string name, ID specialId, object idParam,
     bool isGhost, bool isMutable, bool isUserMutable, Type type, Attributes attributes)
     : this(rangeOrigin, new Name(name), specialId, idParam, false, isGhost, isMutable, isUserMutable, type, attributes) {
   }
 
-  public SpecialField(RangeToken rangeOrigin, Name name, ID specialId, object idParam,
+  public SpecialField(IOrigin rangeOrigin, Name name, ID specialId, object idParam,
     bool hasStaticKeyword, bool isGhost, bool isMutable, bool isUserMutable, Type type, Attributes attributes)
     : base(rangeOrigin, name, hasStaticKeyword, isGhost, isMutable, isUserMutable, type, attributes) {
     Contract.Requires(rangeOrigin != null);
@@ -65,7 +65,7 @@ public override string WhatKind {
     get { return "discriminator"; }
   }
 
-  public DatatypeDiscriminator(RangeToken rangeOrigin, Name name, ID specialId, object idParam, bool isGhost, Type type, Attributes attributes)
+  public DatatypeDiscriminator(IOrigin rangeOrigin, Name name, ID specialId, object idParam, bool isGhost, Type type, Attributes attributes)
     : base(rangeOrigin, name, specialId, idParam, false, isGhost, false, false, type, attributes) {
   }
 }
@@ -81,8 +81,8 @@ void ObjectInvariant() {
     Contract.Invariant(EnclosingCtors.Count == CorrespondingFormals.Count);
   }
 
-  public DatatypeDestructor(RangeToken rangeOrigin, DatatypeCtor enclosingCtor, Formal correspondingFormal, Name name, string compiledName, bool isGhost, Type type, Attributes attributes)
-    : base(rangeOrigin, name, SpecialField.ID.UseIdParam, compiledName, false, isGhost, false, false, type, attributes) {
+  public DatatypeDestructor(IOrigin rangeOrigin, DatatypeCtor enclosingCtor, Formal correspondingFormal, Name name, string compiledName, bool isGhost, Type type, Attributes attributes)
+    : base(rangeOrigin, name, ID.UseIdParam, compiledName, false, isGhost, false, false, type, attributes) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(enclosingCtor != null);
     Contract.Requires(correspondingFormal != null);
diff --git a/Source/DafnyCore/AST/Members/SpecialFunction.cs b/Source/DafnyCore/AST/Members/SpecialFunction.cs
index 8e3cf4229a7..74ce2f9f75e 100644
--- a/Source/DafnyCore/AST/Members/SpecialFunction.cs
+++ b/Source/DafnyCore/AST/Members/SpecialFunction.cs
@@ -4,11 +4,11 @@ namespace Microsoft.Dafny;
 
 public class SpecialFunction : Function, ICallable {
   readonly ModuleDefinition Module;
-  public SpecialFunction(RangeToken rangeOrigin, string name, ModuleDefinition module, bool hasStaticKeyword, bool isGhost,
+  public SpecialFunction(IOrigin rangeToken, string name, ModuleDefinition module, bool hasStaticKeyword, bool isGhost,
     List<TypeParameter> typeArgs, List<Formal> ins, Type resultType,
     List<AttributedExpression> req, Specification<FrameExpression> reads, List<AttributedExpression> ens, Specification<Expression> decreases,
     Expression body, Attributes attributes, IOrigin signatureEllipsis)
-    : base(rangeOrigin, new Name(name), hasStaticKeyword, isGhost, false, typeArgs, ins, null, resultType, req, reads, ens, decreases, body, null, null, attributes, signatureEllipsis) {
+    : base(rangeToken, new Name(name), hasStaticKeyword, isGhost, false, typeArgs, ins, null, resultType, req, reads, ens, decreases, body, null, null, attributes, signatureEllipsis) {
     Module = module;
   }
   ModuleDefinition IASTVisitorContext.EnclosingModule { get { return this.Module; } }
diff --git a/Source/DafnyCore/AST/Members/TwoStateFunction.cs b/Source/DafnyCore/AST/Members/TwoStateFunction.cs
index c2f9896d07b..b063b806be5 100644
--- a/Source/DafnyCore/AST/Members/TwoStateFunction.cs
+++ b/Source/DafnyCore/AST/Members/TwoStateFunction.cs
@@ -6,12 +6,12 @@ namespace Microsoft.Dafny;
 public class TwoStateFunction : Function {
   public override string WhatKind => "twostate function";
   public override string WhatKindMentionGhost => WhatKind;
-  public TwoStateFunction(RangeToken rangeOrigin, Name name, bool hasStaticKeyword, bool isOpaque,
+  public TwoStateFunction(IOrigin rangeToken, Name name, bool hasStaticKeyword, bool isOpaque,
     List<TypeParameter> typeArgs, List<Formal> ins, Formal result, Type resultType,
     List<AttributedExpression> req, Specification<FrameExpression> reads, List<AttributedExpression> ens, Specification<Expression> decreases,
     Expression body, Attributes attributes, IOrigin signatureEllipsis)
-    : base(rangeOrigin, name, hasStaticKeyword, true, isOpaque, typeArgs, ins, result, resultType, req, reads, ens, decreases, body, null, null, attributes, signatureEllipsis) {
-    Contract.Requires(rangeOrigin != null);
+    : base(rangeToken, name, hasStaticKeyword, true, isOpaque, typeArgs, ins, result, resultType, req, reads, ens, decreases, body, null, null, attributes, signatureEllipsis) {
+    Contract.Requires(rangeToken != null);
     Contract.Requires(name != null);
     Contract.Requires(typeArgs != null);
     Contract.Requires(ins != null);
@@ -26,12 +26,12 @@ public TwoStateFunction(RangeToken rangeOrigin, Name name, bool hasStaticKeyword
 
 public class TwoStatePredicate : TwoStateFunction {
   public override string WhatKind => "twostate predicate";
-  public TwoStatePredicate(RangeToken rangeOrigin, Name name, bool hasStaticKeyword, bool isOpaque,
+  public TwoStatePredicate(IOrigin rangeToken, Name name, bool hasStaticKeyword, bool isOpaque,
     List<TypeParameter> typeArgs, List<Formal> ins, Formal result,
     List<AttributedExpression> req, Specification<FrameExpression> reads, List<AttributedExpression> ens, Specification<Expression> decreases,
     Expression body, Attributes attributes, IOrigin signatureEllipsis)
-    : base(rangeOrigin, name, hasStaticKeyword, isOpaque, typeArgs, ins, result, Type.Bool, req, reads, ens, decreases, body, attributes, signatureEllipsis) {
-    Contract.Requires(rangeOrigin != null);
+    : base(rangeToken, name, hasStaticKeyword, isOpaque, typeArgs, ins, result, Type.Bool, req, reads, ens, decreases, body, attributes, signatureEllipsis) {
+    Contract.Requires(rangeToken != null);
     Contract.Requires(name != null);
     Contract.Requires(typeArgs != null);
     Contract.Requires(ins != null);
diff --git a/Source/DafnyCore/AST/Modules/AbstractModuleDecl.cs b/Source/DafnyCore/AST/Modules/AbstractModuleDecl.cs
index acc9ca3b5bd..cbf4818738d 100644
--- a/Source/DafnyCore/AST/Modules/AbstractModuleDecl.cs
+++ b/Source/DafnyCore/AST/Modules/AbstractModuleDecl.cs
@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics.Contracts;
+using System.Linq;
 
 namespace Microsoft.Dafny;
 
@@ -16,11 +17,11 @@ public class AbstractModuleDecl : ModuleDecl, ICanFormat {
 
   public AbstractModuleDecl(Cloner cloner, AbstractModuleDecl original, ModuleDefinition parent)
     : base(cloner, original, parent) {
-    Exports = original.Exports;
+    Exports = original.Exports.Select(cloner.Origin).ToList();
     QId = new ModuleQualifiedId(cloner, original.QId);
   }
 
-  public AbstractModuleDecl(DafnyOptions options, RangeToken rangeOrigin, ModuleQualifiedId qid, Name name,
+  public AbstractModuleDecl(DafnyOptions options, IOrigin rangeOrigin, ModuleQualifiedId qid, Name name,
     ModuleDefinition parent, bool opened, List<IOrigin> exports, Guid cloneId)
     : base(options, rangeOrigin, name, parent, opened, false, cloneId) {
     Contract.Requires(qid != null && qid.Path.Count > 0);
diff --git a/Source/DafnyCore/AST/Modules/AliasModuleDecl.cs b/Source/DafnyCore/AST/Modules/AliasModuleDecl.cs
index 03174ff11fd..ea4274f2472 100644
--- a/Source/DafnyCore/AST/Modules/AliasModuleDecl.cs
+++ b/Source/DafnyCore/AST/Modules/AliasModuleDecl.cs
@@ -28,7 +28,7 @@ public AliasModuleDecl(Cloner cloner, AliasModuleDecl original, ModuleDefinition
        */
       TargetQId.Root = original.TargetQId.Root;
     }
-    Exports = original.Exports;
+    Exports = original.Exports.Select(cloner.Origin).ToList();
   }
 
   public AliasModuleDecl(DafnyOptions options, RangeToken rangeOrigin, ModuleQualifiedId path, Name name,
@@ -62,7 +62,7 @@ public bool SetIndent(int indentBefore, TokenNewIndentCollector formatter) {
   /// </summary>
   public override IOrigin NavigationToken => HasAlias ? base.NavigationToken : (TargetQId.Decl?.NavigationToken ?? base.NavigationToken);
 
-  private bool HasAlias => NameNode.RangeToken.IsSet();
+  private bool HasAlias => NameNode.Origin.IsSet();
 
   public override IOrigin Tok => HasAlias ? NameNode.StartToken : StartToken;
 
diff --git a/Source/DafnyCore/AST/Modules/DefaultClassDecl.cs b/Source/DafnyCore/AST/Modules/DefaultClassDecl.cs
index 1ba074ffe70..260de854555 100644
--- a/Source/DafnyCore/AST/Modules/DefaultClassDecl.cs
+++ b/Source/DafnyCore/AST/Modules/DefaultClassDecl.cs
@@ -12,7 +12,7 @@ public class DefaultClassDecl : TopLevelDeclWithMembers, RevealableTypeDecl {
   public TypeDeclSynonymInfo SynonymInfo { get; set; }
 
   public DefaultClassDecl(ModuleDefinition module, [Captured] List<MemberDecl> members)
-    : base(RangeToken.NoToken, new Name("_default"), module, new List<TypeParameter>(), members, null, false, null) {
+    : base(Dafny.RangeToken.NoToken, new Name("_default"), module, new List<TypeParameter>(), members, null, false, null) {
     Contract.Requires(module != null);
     Contract.Requires(cce.NonNullElements(members));
     this.NewSelfSynonym();
diff --git a/Source/DafnyCore/AST/Modules/DefaultModuleDefinition.cs b/Source/DafnyCore/AST/Modules/DefaultModuleDefinition.cs
index 867cad6c2a8..db08cbf0197 100644
--- a/Source/DafnyCore/AST/Modules/DefaultModuleDefinition.cs
+++ b/Source/DafnyCore/AST/Modules/DefaultModuleDefinition.cs
@@ -11,7 +11,7 @@ public DefaultModuleDefinition(Cloner cloner, DefaultModuleDefinition original)
   }
 
   public DefaultModuleDefinition()
-    : base(RangeToken.NoToken, new Name("_module"), new List<IOrigin>(), ModuleKindEnum.Concrete, false,
+    : base(Dafny.RangeToken.NoToken, new Name("_module"), new List<IOrigin>(), ModuleKindEnum.Concrete, false,
       null, null, null) {
   }
 
diff --git a/Source/DafnyCore/AST/Modules/ExportSignature.cs b/Source/DafnyCore/AST/Modules/ExportSignature.cs
index 25aaf3bd0f1..aabd3cac83c 100644
--- a/Source/DafnyCore/AST/Modules/ExportSignature.cs
+++ b/Source/DafnyCore/AST/Modules/ExportSignature.cs
@@ -42,11 +42,11 @@ public ExportSignature(IOrigin idTok, string id, bool opaque) {
   }
 
   public ExportSignature(Cloner cloner, ExportSignature original) {
-    tok = cloner.Tok(original.Tok);
+    tok = cloner.Origin(original.Tok);
     Id = original.Id;
     Opaque = original.Opaque;
     ClassId = original.ClassId;
-    ClassIdTok = cloner.Tok(original.ClassIdTok);
+    ClassIdTok = cloner.Origin(original.ClassIdTok);
     OwnedTokensCache = new List<IOrigin>() { Tok };
   }
 
diff --git a/Source/DafnyCore/AST/Modules/FileModuleDefinition.cs b/Source/DafnyCore/AST/Modules/FileModuleDefinition.cs
index aef47ef20b1..e0cbe4db640 100644
--- a/Source/DafnyCore/AST/Modules/FileModuleDefinition.cs
+++ b/Source/DafnyCore/AST/Modules/FileModuleDefinition.cs
@@ -13,7 +13,7 @@ public class FileModuleDefinition : ModuleDefinition {
   public List<Include> Includes { get; } = new();
 
   public FileModuleDefinition(IOrigin token) :
-    base(token.ToRange(), new Name("_module"), new List<IOrigin>(),
+    base(token, new Name("_module"), new List<IOrigin>(),
       ModuleKindEnum.Concrete, false, null, null, null) {
     {
     }
diff --git a/Source/DafnyCore/AST/Modules/LiteralModuleDecl.cs b/Source/DafnyCore/AST/Modules/LiteralModuleDecl.cs
index 35f0fa4f20b..86446749fa7 100644
--- a/Source/DafnyCore/AST/Modules/LiteralModuleDecl.cs
+++ b/Source/DafnyCore/AST/Modules/LiteralModuleDecl.cs
@@ -45,7 +45,7 @@ public LiteralModuleDecl(Cloner cloner, LiteralModuleDecl original, ModuleDefini
   }
 
   public LiteralModuleDecl(DafnyOptions options, ModuleDefinition module, ModuleDefinition parent, Guid cloneId)
-    : base(options, module.RangeToken, module.NameNode, parent, false, false, cloneId) {
+    : base(options, module.Origin, module.NameNode, parent, false, false, cloneId) {
     ModuleDef = module;
     BodyStartTok = module.BodyStartTok;
     module.EnclosingLiteralModuleDecl = this;
diff --git a/Source/DafnyCore/AST/Modules/ModuleDecl.cs b/Source/DafnyCore/AST/Modules/ModuleDecl.cs
index 0b6d878369d..c8a27148405 100644
--- a/Source/DafnyCore/AST/Modules/ModuleDecl.cs
+++ b/Source/DafnyCore/AST/Modules/ModuleDecl.cs
@@ -45,7 +45,7 @@ protected ModuleDecl(Cloner cloner, ModuleDecl original, ModuleDefinition parent
     CloneId = original.CloneId;
   }
 
-  protected ModuleDecl(DafnyOptions options, RangeToken rangeOrigin, Name name, ModuleDefinition parent, bool opened, bool isRefining, Guid cloneId)
+  protected ModuleDecl(DafnyOptions options, IOrigin rangeOrigin, Name name, ModuleDefinition parent, bool opened, bool isRefining, Guid cloneId)
     : base(rangeOrigin, name, parent, new List<TypeParameter>(), null, isRefining) {
     Options = options;
     Height = -1;
diff --git a/Source/DafnyCore/AST/Modules/ModuleDefinition.cs b/Source/DafnyCore/AST/Modules/ModuleDefinition.cs
index cdcb28efdd8..b7e146d4035 100644
--- a/Source/DafnyCore/AST/Modules/ModuleDefinition.cs
+++ b/Source/DafnyCore/AST/Modules/ModuleDefinition.cs
@@ -127,7 +127,7 @@ public ModuleDefinition(Cloner cloner, ModuleDefinition original, Name name) : t
 
   public ModuleDefinition(Cloner cloner, ModuleDefinition original) : base(cloner, original) {
     NameNode = original.NameNode;
-    PrefixIds = original.PrefixIds.Select(cloner.Tok).ToList();
+    PrefixIds = original.PrefixIds.Select(cloner.Origin).ToList();
     IsFacade = original.IsFacade;
     Attributes = original.Attributes;
     ModuleKind = original.ModuleKind;
@@ -157,7 +157,7 @@ public ModuleDefinition(Cloner cloner, ModuleDefinition original) : base(cloner,
     }
   }
 
-  public ModuleDefinition(RangeToken tok, Name name, List<IOrigin> prefixIds, ModuleKindEnum moduleKind, bool isFacade,
+  public ModuleDefinition(IOrigin tok, Name name, List<IOrigin> prefixIds, ModuleKindEnum moduleKind, bool isFacade,
     Implements implements, ModuleDefinition parent, Attributes attributes) : base(tok) {
     Contract.Requires(tok != null);
     Contract.Requires(name != null);
@@ -408,7 +408,8 @@ public bool IsEssentiallyEmptyModuleBody() {
     return TopLevelDecls.All(decl => decl.IsEssentiallyEmpty());
   }
 
-  public IOrigin NavigationToken => tok;
+  public IOrigin NavigationToken => NameNode.Origin;
+
   public override IEnumerable<INode> Children =>
     Attributes.AsEnumerable().
     Concat<Node>(DefaultClasses).
@@ -633,7 +634,7 @@ public void ProcessPrefixNamedModules() {
     foreach (var (name, prefixNamedModules) in prefixModulesByFirstPart) {
       var prefixNameModule = prefixNamedModules.First();
       var firstPartToken = prefixNameModule.Parts[0];
-      var modDef = new ModuleDefinition(RangeToken.NoToken, new Name(firstPartToken.ToRange(), name), new List<IOrigin>(), ModuleKindEnum.Concrete,
+      var modDef = new ModuleDefinition(Dafny.RangeToken.NoToken, new Name(firstPartToken, name), new List<IOrigin>(), ModuleKindEnum.Concrete,
         false, null, this, null);
       // Add the new module to the top-level declarations of its parent and then bind its names as usual
 
@@ -845,7 +846,7 @@ public ModuleSignature RegisterTopLevelDecls(ModuleResolver resolver, bool useIm
 
             // create and add the query "method" (field, really)
             var queryName = ctor.NameNode.Append("?");
-            var query = new DatatypeDiscriminator(ctor.RangeToken, queryName, SpecialField.ID.UseIdParam, "is_" + ctor.GetCompileName(resolver.Options),
+            var query = new DatatypeDiscriminator(ctor.Origin, queryName, SpecialField.ID.UseIdParam, "is_" + ctor.GetCompileName(resolver.Options),
               ctor.IsGhost, Type.Bool, null);
             query.InheritVisibility(dt);
             query.EnclosingClass = dt; // resolve here
@@ -896,7 +897,7 @@ public ModuleSignature RegisterTopLevelDecls(ModuleResolver resolver, bool useIm
               dtor.AddAnotherEnclosingCtor(ctor, formal);
             } else {
               // either the destructor has no explicit name, or this constructor declared another destructor with this name, or no previous destructor had this name
-              dtor = new DatatypeDestructor(formal.RangeToken, ctor, formal, new Name(formal.RangeToken, formal.Name), "dtor_" + formal.CompileName,
+              dtor = new DatatypeDestructor(formal.Origin, ctor, formal, /* should be formal.NameNode */ new Name(formal.StartToken, formal.Name), "dtor_" + formal.CompileName,
                 formal.IsGhost, formal.Type, null);
               dtor.InheritVisibility(dt);
               dtor.EnclosingClass = dt; // resolve here
diff --git a/Source/DafnyCore/AST/Modules/ModuleExportDecl.cs b/Source/DafnyCore/AST/Modules/ModuleExportDecl.cs
index 893289c643b..cc1845f498f 100644
--- a/Source/DafnyCore/AST/Modules/ModuleExportDecl.cs
+++ b/Source/DafnyCore/AST/Modules/ModuleExportDecl.cs
@@ -26,7 +26,7 @@ public class ModuleExportDecl : ModuleDecl, ICanFormat {
   public ModuleExportDecl(Cloner cloner, ModuleExportDecl original, ModuleDefinition parent)
     : base(cloner, original, parent) {
     Exports = original.Exports.Select(s => new ExportSignature(cloner, s)).ToList();
-    Extends = original.Extends.Select(cloner.Tok).ToList();
+    Extends = original.Extends.Select(cloner.Origin).ToList();
     ProvideAll = original.ProvideAll;
     RevealAll = original.RevealAll;
     IsRefining = original.IsRefining;
@@ -35,7 +35,7 @@ public ModuleExportDecl(Cloner cloner, ModuleExportDecl original, ModuleDefiniti
     SetupDefaultSignature();
   }
 
-  public ModuleExportDecl(DafnyOptions options, RangeToken rangeOrigin, Name name, ModuleDefinition parent,
+  public ModuleExportDecl(DafnyOptions options, IOrigin rangeOrigin, Name name, ModuleDefinition parent,
     List<ExportSignature> exports, List<IOrigin> extends,
     bool provideAll, bool revealAll, bool isDefault, bool isRefining, Guid cloneId)
     : base(options, rangeOrigin, name, parent, false, isRefining, cloneId) {
diff --git a/Source/DafnyCore/AST/Modules/ModuleQualifiedId.cs b/Source/DafnyCore/AST/Modules/ModuleQualifiedId.cs
index b31be83abe5..5cf05ecb7f3 100644
--- a/Source/DafnyCore/AST/Modules/ModuleQualifiedId.cs
+++ b/Source/DafnyCore/AST/Modules/ModuleQualifiedId.cs
@@ -62,14 +62,15 @@ public void SetTarget(ModuleDecl m) {
     }
   }
 
+  public override IOrigin RangeOrigin {
+    set => throw new NotImplementedException();
+  }
+
   public override IOrigin Tok => Path.Last().Tok;
   public override IEnumerable<INode> Children => Enumerable.Empty<Node>();
   public override IEnumerable<INode> PreResolveChildren => Children;
 
-  public override RangeToken RangeToken {
-    get => new(Path.First().StartToken, Path.Last().EndToken);
-    set => throw new NotSupportedException();
-  }
+  public override IOrigin Origin => Path.First().Origin;
 
   public IOrigin NavigationToken => Path.Last().StartToken;
 
diff --git a/Source/DafnyCore/AST/Modules/ScopeCloner.cs b/Source/DafnyCore/AST/Modules/ScopeCloner.cs
index 8d459db5384..6147d1301af 100644
--- a/Source/DafnyCore/AST/Modules/ScopeCloner.cs
+++ b/Source/DafnyCore/AST/Modules/ScopeCloner.cs
@@ -95,7 +95,7 @@ public override TopLevelDecl CloneDeclaration(TopLevelDecl d, ModuleDefinition n
       var characteristics = TypeParameter.GetExplicitCharacteristics(d);
       var members = based is TopLevelDeclWithMembers tm ? tm.Members : new List<MemberDecl>();
       // copy the newParent traits only if "d" is already an AbstractTypeDecl and is being export-revealed
-      var otd = new AbstractTypeDecl(Range(d.RangeToken), d.NameNode.Clone(this), newParent, characteristics, tps,
+      var otd = new AbstractTypeDecl(Origin(d.Origin), d.NameNode.Clone(this), newParent, characteristics, tps,
         new List<Type>(), // omit the newParent traits
         members, CloneAttributes(d.Attributes), d.IsRefining);
       based = otd;
@@ -114,7 +114,7 @@ public override Field CloneField(Field f) {
     if (f is ConstantField { Rhs: not null } cf && !RevealedInScope(f)) {
       // We erase the RHS value. While we do that, we must also make sure the declaration does have a type, so instead of
       // cloning cf.Type, we assume "f" has been resolved and clone cf.Type.NormalizeExpandKeepConstraints().
-      return new ConstantField(Range(cf.RangeToken), cf.NameNode.Clone(this), null, cf.HasStaticKeyword, cf.IsGhost, cf.IsOpaque, CloneType(cf.Type.NormalizeExpandKeepConstraints()), CloneAttributes(cf.Attributes));
+      return new ConstantField(Origin(cf.Origin), cf.NameNode.Clone(this), null, cf.HasStaticKeyword, cf.IsGhost, cf.IsOpaque, CloneType(cf.Type.NormalizeExpandKeepConstraints()), CloneAttributes(cf.Attributes));
     }
     return base.CloneField(f);
   }
@@ -126,7 +126,7 @@ public override Function CloneFunction(Function f, string newName = null) {
       Contract.Assert(basef.Body != null); // a function-by-method has a nonempty .Body
       if (RevealedInScope(f)) {
         // For an "export reveals", use an empty (but not absent) by-method part.
-        basef.ByMethodBody = new BlockStmt(basef.ByMethodBody.RangeToken, new List<Statement>());
+        basef.ByMethodBody = new BlockStmt(basef.ByMethodBody.Origin, new List<Statement>());
       } else {
         // For an "export provides", remove the by-method part altogether.
         basef.ByMethodTok = null;
diff --git a/Source/DafnyCore/AST/OriginWrapper.cs b/Source/DafnyCore/AST/OriginWrapper.cs
index c0bcf1b661f..33b52413363 100644
--- a/Source/DafnyCore/AST/OriginWrapper.cs
+++ b/Source/DafnyCore/AST/OriginWrapper.cs
@@ -5,88 +5,87 @@ namespace Microsoft.Dafny;
 
 public abstract class OriginWrapper : IOrigin {
 
-  public readonly IOrigin WrappedToken;
-  protected OriginWrapper(IOrigin wrappedToken) {
-    Contract.Requires(wrappedToken != null);
-    WrappedToken = wrappedToken;
+  public readonly IOrigin WrappedOrigin;
+  protected OriginWrapper(IOrigin wrappedOrigin) {
+    Contract.Requires(wrappedOrigin != null);
+    WrappedOrigin = wrappedOrigin;
   }
 
   public abstract IOrigin WithVal(string newVal);
-  public virtual bool IsCopy => WrappedToken.IsCopy;
+  public virtual bool IsCopy => WrappedOrigin.IsCopy;
 
   public virtual int col {
-    get { return WrappedToken.col; }
-    set { WrappedToken.col = value; }
+    get => WrappedOrigin.col;
+    set => WrappedOrigin.col = value;
   }
 
-  public string ActualFilename => WrappedToken.ActualFilename;
+  public bool IsMissingRange => WrappedOrigin.IsMissingRange;
+  public virtual bool IsInherited(ModuleDefinition d) => WrappedOrigin.IsInherited(d);
+  public virtual Token Center => WrappedOrigin.Center;
+  public virtual Token StartToken => WrappedOrigin.StartToken;
+  public virtual Token EndToken => WrappedOrigin.EndToken;
+  public virtual bool ContainsRange => WrappedOrigin.ContainsRange;
+  public string ActualFilename => WrappedOrigin.ActualFilename;
 
-  public virtual string Filepath => WrappedToken.Filepath;
+  public virtual string Filepath => WrappedOrigin.Filepath;
 
   public Uri Uri {
-    get => WrappedToken.Uri;
-    set => WrappedToken.Uri = value;
+    get => WrappedOrigin.Uri;
+    set => WrappedOrigin.Uri = value;
   }
 
-  public bool IsValid {
-    get { return WrappedToken.IsValid; }
-  }
+  public bool IsValid => WrappedOrigin.IsValid;
 
   public virtual bool IsSourceToken => false;
 
   public int kind {
-    get { return WrappedToken.kind; }
-    set { WrappedToken.kind = value; }
+    get => WrappedOrigin.kind;
+    set => WrappedOrigin.kind = value;
   }
   public virtual int line {
-    get { return WrappedToken.line; }
-    set { WrappedToken.line = value; }
+    get => WrappedOrigin.line;
+    set => WrappedOrigin.line = value;
   }
   public virtual int pos {
-    get { return WrappedToken.pos; }
-    set { WrappedToken.pos = value; }
+    get => WrappedOrigin.pos;
+    set => WrappedOrigin.pos = value;
   }
 
   public virtual string val {
-    get { return WrappedToken.val; }
-    set { WrappedToken.val = value; }
+    get => WrappedOrigin.val;
+    set => WrappedOrigin.val = value;
   }
   public virtual string LeadingTrivia {
-    get { return WrappedToken.LeadingTrivia; }
-    set { throw new NotSupportedException(); }
+    get => WrappedOrigin.LeadingTrivia;
+    set => throw new NotSupportedException();
   }
   public virtual string TrailingTrivia {
-    get { return WrappedToken.TrailingTrivia; }
-    set { throw new NotSupportedException(); }
+    get => WrappedOrigin.TrailingTrivia;
+    set => throw new NotSupportedException();
   }
   public virtual Token Next {
-    get { return WrappedToken.Next; }
-    set { throw new NotSupportedException(); }
+    get => WrappedOrigin.Next;
+    set => throw new NotSupportedException();
   }
   public virtual Token Prev {
-    get { return WrappedToken.Prev; }
-    set { throw new NotSupportedException(); }
+    get => WrappedOrigin.Prev;
+    set => throw new NotSupportedException();
   }
 
   public int CompareTo(IOrigin other) {
-    return WrappedToken.CompareTo(other);
+    return WrappedOrigin.CompareTo(other);
   }
 
   public int CompareTo(Boogie.IToken other) {
-    return WrappedToken.CompareTo(other);
+    return WrappedOrigin.CompareTo(other);
   }
 
   /// <summary>
   ///  Removes token wrappings from a given token, so that it returns the bare token
   /// </summary>
   public static IOrigin Unwrap(IOrigin token, bool includeRanges = false) {
-    if (token is OriginWrapper wrapper
-        && (includeRanges || token is not RangeToken)) {
-      return Unwrap(wrapper.WrappedToken);
-    }
-
-    if (token is RangeToken rangeToken) {
-      return new RangeToken(Unwrap(rangeToken.StartToken), Unwrap(rangeToken.EndToken));
+    if (token is OriginWrapper wrapper) {
+      return Unwrap(wrapper.WrappedOrigin);
     }
 
     return token;
diff --git a/Source/DafnyCore/AST/Program.cs b/Source/DafnyCore/AST/Program.cs
index f197fe2e74c..23af4c467c2 100644
--- a/Source/DafnyCore/AST/Program.cs
+++ b/Source/DafnyCore/AST/Program.cs
@@ -110,12 +110,12 @@ public string Name {
 
   /// Get the first token that is in the same file as the DefaultModule.RootToken.FileName
   /// (skips included tokens)
-  public IOrigin GetStartOfFirstFileToken() {
+  public Token GetStartOfFirstFileToken() {
     return GetFirstTokenForUri(Compilation.RootSourceUris[0]);
   }
 
   public Token GetFirstTokenForUri(Uri uri) {
-    return (Token)OriginWrapper.Unwrap(this.FindNodesInUris(uri).MinBy(n => n.RangeToken.StartToken.pos)?.StartToken);
+    return this.FindNodesInUris(uri).MinBy(n => n.Origin.StartToken.pos)?.StartToken;
   }
 
   public override IEnumerable<INode> Children => new[] { DefaultModule };
diff --git a/Source/DafnyCore/AST/RangeToken.cs b/Source/DafnyCore/AST/RangeToken.cs
index 9cd02f70ba1..8321bf71b03 100644
--- a/Source/DafnyCore/AST/RangeToken.cs
+++ b/Source/DafnyCore/AST/RangeToken.cs
@@ -1,19 +1,21 @@
+#nullable enable
 using System;
-using System.Text;
+using Microsoft.Boogie;
 
 namespace Microsoft.Dafny;
 
-public class RangeToken : OriginWrapper {
-  public IOrigin StartToken => WrappedToken;
+public class RangeToken : IOrigin {
+  public bool IsMissingRange => false;
 
-  public IOrigin EndToken => endToken ?? StartToken;
-
-  public bool InclusiveEnd => endToken != null;
+  public bool IsInherited(ModuleDefinition d) {
+    return false;
+  }
 
-  public override bool Equals(object obj) {
+  public override bool Equals(object? obj) {
     if (obj is RangeToken other) {
       return StartToken.Equals(other.StartToken) && EndToken.Equals(other.EndToken);
     }
+
     return false;
   }
 
@@ -21,77 +23,97 @@ public override int GetHashCode() {
     return HashCode.Combine(StartToken.GetHashCode(), EndToken.GetHashCode());
   }
 
-  public DafnyRange ToDafnyRange(bool includeTrailingWhitespace = false) {
-    var startLine = StartToken.line - 1;
-    var startColumn = StartToken.col - 1;
-    var endLine = EndToken.line - 1;
-    int whitespaceOffset = 0;
-    if (includeTrailingWhitespace) {
-      string trivia = EndToken.TrailingTrivia;
-      // Don't want to remove newlines or comments -- just spaces and tabs
-      while (whitespaceOffset < trivia.Length && (trivia[whitespaceOffset] == ' ' || trivia[whitespaceOffset] == '\t')) {
-        whitespaceOffset++;
-      }
-    }
+  public Token Center { get; }
 
-    var endColumn = EndToken.col + (InclusiveEnd ? EndToken.val.Length : 0) + whitespaceOffset - 1;
-    return new DafnyRange(
-      new DafnyPosition(startLine, startColumn),
-      new DafnyPosition(endLine, endColumn));
-  }
+  public Token StartToken { get; }
+  public Token Centre => Center;
+
+  public Token EndToken => endToken ?? StartToken;
+  public bool ContainsRange => true;
 
-  public RangeToken(IOrigin startToken, IOrigin endToken) : base(startToken) {
+  public bool InclusiveEnd => endToken != null;
+
+  public RangeToken(Token startToken, Token? endToken, Token? center = null) {
+    StartToken = startToken;
+    Center = center ?? startToken;
     this.endToken = endToken;
   }
+  public int Length() {
+    return EndToken.pos - StartToken.pos;
+  }
 
-  public string PrintOriginal() {
-    var token = StartToken;
-    var originalString = new StringBuilder();
-    originalString.Append(token.val);
-    while (token.Next != null && token.pos < EndToken.pos) {
-      originalString.Append(token.TrailingTrivia);
-      token = token.Next;
-      originalString.Append(token.LeadingTrivia);
-      originalString.Append(token.val);
-    }
+  public static IOrigin NoToken => Token.NoToken; // TODO inline
+  private readonly Token? endToken;
 
-    return originalString.ToString();
+  public Uri Uri {
+    get => Center.Uri;
+    set => Center.Uri = value;
   }
 
-  public int Length() {
-    return EndToken.pos - StartToken.pos;
+  public string TrailingTrivia {
+    get => Center.TrailingTrivia;
+    set => Center.TrailingTrivia = value;
+  }
+
+  public string LeadingTrivia {
+    get => Center.LeadingTrivia;
+    set => Center.LeadingTrivia = value;
+  }
+
+  public Token Next {
+    get => Center.Next;
+    set => Center.Next = value;
+  }
+
+  public Token Prev {
+    get => Center.Prev;
+    set => Center.Prev = value;
   }
 
-  public RangeToken MakeAutoGenerated() {
-    return new RangeToken(new AutoGeneratedOrigin(StartToken), EndToken);
+  public IOrigin WithVal(string newValue) {
+    throw new NotImplementedException(); // TODO why is this needed?
   }
 
-  public RangeToken MakeRefined(ModuleDefinition module) {
-    return new RangeToken(new RefinementOrigin(StartToken, module), EndToken);
+  public bool IsCopy => false;
+
+  public bool IsSourceToken => true;
+
+  public int kind {
+    get => Center.kind;
+    set => Center.kind = value;
+  }
+
+  public int pos {
+    get => Center.pos;
+    set => Center.pos = value;
   }
 
-  // TODO rename to Generated, and Token.NoToken to Token.Generated, and remove AutoGeneratedToken.
-  public static RangeToken NoToken = new(Token.NoToken, Token.NoToken);
-  private readonly IOrigin endToken;
+  public int col {
+    get => Center.col;
+    set => Center.col = value;
+  }
+
+  public int line {
+    get => Center.line;
+    set => Center.line = value;
+  }
 
-  public override IOrigin WithVal(string newVal) {
-    throw new NotImplementedException();
+  public string val {
+    get => Center.val;
+    set => Center.val = value;
   }
 
-  public override bool IsSourceToken => this != NoToken;
+  public bool IsValid => Center.IsValid;
 
   public BoogieRangeOrigin ToToken() {
     return new BoogieRangeOrigin(StartToken, EndToken, null);
   }
 
-  public bool Contains(IOrigin otherToken) {
-    return StartToken.Uri == otherToken.Uri &&
-           StartToken.pos <= otherToken.pos &&
-           (EndToken == null || otherToken.pos <= EndToken.pos);
+  public int CompareTo(IToken? other) {
+    return Center.CompareTo(other);
   }
 
-  public bool Intersects(RangeToken other) {
-    return !(other.EndToken.pos + other.EndToken.val.Length <= StartToken.pos
-             || EndToken.pos + EndToken.val.Length <= other.StartToken.pos);
+  public int CompareTo(IOrigin? other) {
+    return Center.CompareTo((IToken)other!);
   }
 }
\ No newline at end of file
diff --git a/Source/DafnyCore/AST/ShouldCompileOrVerify.cs b/Source/DafnyCore/AST/ShouldCompileOrVerify.cs
index 80bb13eca4d..e8afa0b2fb0 100644
--- a/Source/DafnyCore/AST/ShouldCompileOrVerify.cs
+++ b/Source/DafnyCore/AST/ShouldCompileOrVerify.cs
@@ -35,7 +35,7 @@ public static bool ShouldCompile(this ModuleDefinition module, CompilationData p
   }
 
   public static bool ShouldVerify(this INode declaration, CompilationData compilation) {
-    if (declaration.Tok == Token.NoToken) {
+    if (ReferenceEquals(declaration.Tok, Token.NoToken)) {
       // Required for DefaultModuleDefinition.
       return true;
     }
diff --git a/Source/DafnyCore/AST/Statements/Assignment/AssignOrReturnStmt.cs b/Source/DafnyCore/AST/Statements/Assignment/AssignOrReturnStmt.cs
index ae4a28022c2..65eb980adc2 100644
--- a/Source/DafnyCore/AST/Statements/Assignment/AssignOrReturnStmt.cs
+++ b/Source/DafnyCore/AST/Statements/Assignment/AssignOrReturnStmt.cs
@@ -14,16 +14,6 @@ public class AssignOrReturnStmt : ConcreteAssignStatement, ICloneable<AssignOrRe
   public readonly AttributedToken KeywordToken;
   [FilledInDuringResolution] public readonly List<Statement> ResolvedStatements = new();
   public override IEnumerable<Statement> SubStatements => ResolvedStatements;
-  public override IOrigin Tok {
-    get {
-      var result = Rhs.StartToken.Prev;
-      if (char.IsLetter(result.val[0])) {
-        // Jump to operator if we're on an assume/expect/assert keyword.
-        result = result.Prev;
-      }
-      return result;
-    }
-  }
 
   public override IEnumerable<INode> Children => ResolvedStatements;
 
@@ -53,7 +43,7 @@ public AssignOrReturnStmt(Cloner cloner, AssignOrReturnStmt original) : base(clo
     }
   }
 
-  public AssignOrReturnStmt(RangeToken rangeOrigin, List<Expression> lhss, ExprRhs rhs, AttributedToken keywordToken, List<AssignmentRhs> rhss)
+  public AssignOrReturnStmt(IOrigin rangeOrigin, List<Expression> lhss, ExprRhs rhs, AttributedToken keywordToken, List<AssignmentRhs> rhss)
     : base(rangeOrigin, lhss) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(lhss != null);
@@ -266,9 +256,9 @@ private void DesugarElephantStatement(bool expectExtract, Expression lhsExtract,
     ModuleResolver resolver, Method enclosingMethod) {
 
     var temp = resolver.FreshTempVarName("valueOrError", enclosingMethod);
-    var lhss = new List<LocalVariable>() { new LocalVariable(RangeToken, temp, new InferredTypeProxy(), false) };
+    var lhss = new List<LocalVariable>() { new LocalVariable(Origin, temp, new InferredTypeProxy(), false) };
     // "var temp ;"
-    ResolvedStatements.Add(new VarDeclStmt(RangeToken, lhss, null));
+    ResolvedStatements.Add(new VarDeclStmt(Origin, lhss, null));
     var lhss2 = new List<Expression>() { new IdentifierExpr(Tok, temp) };
     for (int k = (expectExtract ? 1 : 0); k < Lhss.Count; ++k) {
       lhss2.Add(Lhss[k]);
@@ -289,7 +279,7 @@ private void DesugarElephantStatement(bool expectExtract, Expression lhsExtract,
       }
     }
     // " temp, ... := MethodOrExpression, ...;"
-    var up = new AssignStatement(RangeToken, lhss2, rhss2);
+    var up = new AssignStatement(Origin, lhss2, rhss2);
     if (expectExtract) {
       up.OriginalInitialLhs = Lhss.Count == 0 ? null : Lhss[0];
     }
@@ -320,14 +310,14 @@ private void DesugarElephantStatement(bool expectExtract, Expression lhsExtract,
 
       ResolvedStatements.Add(
         // "if temp.IsFailure()"
-        new IfStmt(RangeToken, false, resolver.VarDotMethod(Tok, temp, "IsFailure"),
+        new IfStmt(Origin, false, resolver.VarDotMethod(Tok, temp, "IsFailure"),
           // THEN: { out := temp.PropagateFailure(); return; }
-          new BlockStmt(RangeToken, new List<Statement>() {
-            new AssignStatement(RangeToken,
+          new BlockStmt(Origin, new List<Statement>() {
+            new AssignStatement(Origin,
               new List<Expression>() { ident },
               new List<AssignmentRhs>() { new ExprRhs(resolver.VarDotMethod(Tok, temp, "PropagateFailure")) }
             ),
-            new ReturnStmt(RangeToken, null),
+            new ReturnStmt(Origin, null),
           }),
           // ELSE: no else block
           null
@@ -338,7 +328,7 @@ private void DesugarElephantStatement(bool expectExtract, Expression lhsExtract,
       // "y := temp.Extract();"
       var lhs = Lhss[0];
       ResolvedStatements.Add(
-        new AssignStatement(RangeToken,
+        new AssignStatement(Origin,
           new List<Expression>() { lhsExtract },
           new List<AssignmentRhs>() { new ExprRhs(resolver.VarDotMethod(Tok, temp, "Extract")) }
         ));
diff --git a/Source/DafnyCore/AST/Statements/Assignment/AssignStatement.cs b/Source/DafnyCore/AST/Statements/Assignment/AssignStatement.cs
index 60ab1a66be5..a83a7982dd3 100644
--- a/Source/DafnyCore/AST/Statements/Assignment/AssignStatement.cs
+++ b/Source/DafnyCore/AST/Statements/Assignment/AssignStatement.cs
@@ -5,25 +5,13 @@
 namespace Microsoft.Dafny;
 
 /// <summary>
-/// Parsed from ":="
+/// Parsed from ":=" or a call without results
 /// </summary>
 public class AssignStatement : ConcreteAssignStatement, ICloneable<AssignStatement>, ICanResolve {
   public readonly List<AssignmentRhs> Rhss;
   public readonly bool CanMutateKnownState;
   public Expression OriginalInitialLhs = null;
 
-  public override IOrigin Tok {
-    get {
-      var firstRhs = Rhss.First();
-      if (firstRhs.StartToken != StartToken) {
-        // If there is an operator, use it as a token
-        return firstRhs.StartToken.Prev;
-      }
-
-      return firstRhs.Tok;
-    }
-  }
-
   [FilledInDuringResolution] public List<Statement> ResolvedStatements;
   public override IEnumerable<Statement> SubStatements => Children.OfType<Statement>();
 
@@ -53,7 +41,7 @@ public AssignStatement(Cloner cloner, AssignStatement original) : base(cloner, o
     }
   }
 
-  public AssignStatement(RangeToken rangeOrigin, List<Expression> lhss, List<AssignmentRhs> rhss)
+  public AssignStatement(IOrigin rangeOrigin, List<Expression> lhss, List<AssignmentRhs> rhss)
     : base(rangeOrigin, lhss) {
     Contract.Requires(cce.NonNullElements(lhss));
     Contract.Requires(cce.NonNullElements(rhss));
@@ -61,7 +49,7 @@ public AssignStatement(RangeToken rangeOrigin, List<Expression> lhss, List<Assig
     Rhss = rhss;
     CanMutateKnownState = false;
   }
-  public AssignStatement(RangeToken rangeOrigin, List<Expression> lhss, List<AssignmentRhs> rhss, bool mutate)
+  public AssignStatement(IOrigin rangeOrigin, List<Expression> lhss, List<AssignmentRhs> rhss, bool mutate)
     : base(rangeOrigin, lhss) {
     Contract.Requires(cce.NonNullElements(lhss));
     Contract.Requires(cce.NonNullElements(rhss));
@@ -136,7 +124,7 @@ public override void Resolve(ModuleResolver resolver, ResolutionContext resoluti
       } else if (resolver.Reporter.Count(ErrorLevel.Error) == errorCountBeforeCheckingLhs) {
         // add the statements here in a sequence, but don't use that sequence later for translation (instead, should translate properly as multi-assignment)
         for (int i = 0; i < Lhss.Count; i++) {
-          var a = new SingleAssignStmt(RangeToken, Lhss[i].Resolved, Rhss[i]);
+          var a = new SingleAssignStmt(Origin, Lhss[i].Resolved, Rhss[i]);
           ResolvedStatements.Add(a);
         }
       }
@@ -156,7 +144,7 @@ public override void Resolve(ModuleResolver resolver, ResolutionContext resoluti
           if (tr.CanAffectPreviouslyKnownExpressions) {
             resolver.Reporter.Error(MessageSource.Resolver, tr.Tok, "can only have initialization methods which modify at most 'this'.");
           } else if (resolver.Reporter.Count(ErrorLevel.Error) == errorCountBeforeCheckingLhs) {
-            var a = new SingleAssignStmt(RangeToken, Lhss[0].Resolved, tr);
+            var a = new SingleAssignStmt(Origin, Lhss[0].Resolved, tr);
             ResolvedStatements.Add(a);
           }
         }
@@ -172,7 +160,7 @@ public override void Resolve(ModuleResolver resolver, ResolutionContext resoluti
           Contract.Assert(2 <= Lhss.Count);  // the parser allows 0 Lhss only if the whole statement looks like an expression (not a TypeRhs)
           resolver.Reporter.Error(MessageSource.Resolver, Lhss[1].tok, "the number of left-hand sides ({0}) and right-hand sides ({1}) must match for a multi-assignment", Lhss.Count, Rhss.Count);
         } else if (resolver.Reporter.Count(ErrorLevel.Error) == errorCountBeforeCheckingLhs) {
-          var a = new SingleAssignStmt(RangeToken, Lhss[0].Resolved, Rhss[0]);
+          var a = new SingleAssignStmt(Origin, Lhss[0].Resolved, Rhss[0]);
           ResolvedStatements.Add(a);
         }
       } else if (resolver.Reporter.Count(ErrorLevel.Error) == errorCountBeforeCheckingLhs) {
@@ -181,7 +169,7 @@ public override void Resolve(ModuleResolver resolver, ResolutionContext resoluti
         foreach (var ll in Lhss) {
           resolvedLhss.Add(ll.Resolved);
         }
-        CallStmt a = new CallStmt(RangeToken, resolvedLhss, methodCallInfo.Callee, methodCallInfo.ActualParameters, methodCallInfo.Tok);
+        CallStmt a = new CallStmt(Origin, resolvedLhss, methodCallInfo.Callee, methodCallInfo.ActualParameters, methodCallInfo.Tok);
         a.OriginalInitialLhs = OriginalInitialLhs;
         ResolvedStatements.Add(a);
       }
diff --git a/Source/DafnyCore/AST/Statements/Assignment/AssignSuchThatStmt.cs b/Source/DafnyCore/AST/Statements/Assignment/AssignSuchThatStmt.cs
index c9bf69b45d5..283c827b03e 100644
--- a/Source/DafnyCore/AST/Statements/Assignment/AssignSuchThatStmt.cs
+++ b/Source/DafnyCore/AST/Statements/Assignment/AssignSuchThatStmt.cs
@@ -15,17 +15,6 @@ public class AssignSuchThatStmt : ConcreteAssignStatement, ICloneable<AssignSuch
   public override IEnumerable<INode> PreResolveChildren =>
     Lhss.Concat<Node>(new List<Node>() { Expr });
 
-  public override IOrigin Tok {
-    get {
-      var result = Expr.StartToken.Prev;
-      if (char.IsLetter(result.val[0])) {
-        // Jump to operator if we're on an assume keyword.
-        result = result.Prev;
-      }
-      return result;
-    }
-  }
-
   [FilledInDuringResolution] public List<BoundedPool> Bounds;  // null for a ghost statement
   // invariant Bounds == null || Bounds.Count == BoundVars.Count;
   [FilledInDuringResolution] public List<IVariable> MissingBounds;  // remains "null" if bounds can be found
@@ -58,7 +47,7 @@ public AssignSuchThatStmt(Cloner cloner, AssignSuchThatStmt original) : base(clo
   /// "assumeToken" is allowed to be "null", in which case the verifier will check that a RHS value exists.
   /// If "assumeToken" is non-null, then it should denote the "assume" keyword used in the statement.
   /// </summary>
-  public AssignSuchThatStmt(RangeToken rangeOrigin, List<Expression> lhss, Expression expr, AttributedToken assumeToken, Attributes attrs)
+  public AssignSuchThatStmt(IOrigin rangeOrigin, List<Expression> lhss, Expression expr, AttributedToken assumeToken, Attributes attrs)
     : base(rangeOrigin, lhss, attrs) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(cce.NonNullElements(lhss));
diff --git a/Source/DafnyCore/AST/Statements/Assignment/AssignmentRhs.cs b/Source/DafnyCore/AST/Statements/Assignment/AssignmentRhs.cs
index ee28b6f843c..c055d617d1f 100644
--- a/Source/DafnyCore/AST/Statements/Assignment/AssignmentRhs.cs
+++ b/Source/DafnyCore/AST/Statements/Assignment/AssignmentRhs.cs
@@ -17,9 +17,9 @@ public bool HasAttributes() {
   }
 
   internal AssignmentRhs(Cloner cloner, AssignmentRhs original) {
-    tok = cloner.Tok(original.tok);
+    tok = cloner.Origin(original.tok);
     Attributes = cloner.CloneAttributes(original.Attributes);
-    RangeToken = cloner.Range(original.RangeOrigin);
+    RangeOrigin = cloner.Origin(original.rangeToken);
   }
 
   internal AssignmentRhs(IOrigin tok, Attributes attrs = null) {
diff --git a/Source/DafnyCore/AST/Statements/Assignment/AttributedToken.cs b/Source/DafnyCore/AST/Statements/Assignment/AttributedToken.cs
index 4d2eae1a113..c698a1bcebc 100644
--- a/Source/DafnyCore/AST/Statements/Assignment/AttributedToken.cs
+++ b/Source/DafnyCore/AST/Statements/Assignment/AttributedToken.cs
@@ -11,7 +11,7 @@ namespace Microsoft.Dafny;
 /// `{:axiom}` attribute is directly attached to the statement-level
 /// attributes).
 /// </summary>
-public record AttributedToken(IOrigin Token, Attributes Attrs) : IAttributeBearingDeclaration {
+public record AttributedToken(Token Token, Attributes Attrs) : IAttributeBearingDeclaration {
   Attributes IAttributeBearingDeclaration.Attributes {
     get => Attrs;
     set => throw new System.NotImplementedException();
diff --git a/Source/DafnyCore/AST/Statements/Assignment/ConcreteAssignStatement.cs b/Source/DafnyCore/AST/Statements/Assignment/ConcreteAssignStatement.cs
index 657d4b95507..d7058b0bebf 100644
--- a/Source/DafnyCore/AST/Statements/Assignment/ConcreteAssignStatement.cs
+++ b/Source/DafnyCore/AST/Statements/Assignment/ConcreteAssignStatement.cs
@@ -14,7 +14,7 @@ protected ConcreteAssignStatement(Cloner cloner, ConcreteAssignStatement origina
     Lhss = original.Lhss.Select(cloner.CloneExpr).ToList();
   }
 
-  public ConcreteAssignStatement(RangeToken rangeOrigin, List<Expression> lhss, Attributes attrs = null)
+  public ConcreteAssignStatement(IOrigin rangeOrigin, List<Expression> lhss, Attributes attrs = null)
     : base(rangeOrigin, attrs) {
     Contract.Requires(cce.NonNullElements(lhss));
     Lhss = lhss;
diff --git a/Source/DafnyCore/AST/Statements/Assignment/LocalVariable.cs b/Source/DafnyCore/AST/Statements/Assignment/LocalVariable.cs
index 0920839d884..b109c1db23c 100644
--- a/Source/DafnyCore/AST/Statements/Assignment/LocalVariable.cs
+++ b/Source/DafnyCore/AST/Statements/Assignment/LocalVariable.cs
@@ -22,8 +22,6 @@ void ObjectInvariant() {
     Contract.Invariant(SyntacticType != null);
   }
 
-  public override IOrigin Tok => RangeToken.StartToken;
-
   public LocalVariable(Cloner cloner, LocalVariable original)
     : base(cloner, original) {
     name = original.Name;
@@ -36,7 +34,7 @@ public LocalVariable(Cloner cloner, LocalVariable original)
     }
   }
 
-  public LocalVariable(RangeToken rangeOrigin, string name, Type type, bool isGhost)
+  public LocalVariable(IOrigin rangeOrigin, string name, Type type, bool isGhost)
     : base(rangeOrigin) {
     Contract.Requires(name != null);
     Contract.Requires(type != null);  // can be a proxy, though
@@ -131,7 +129,7 @@ public void MakeGhost() {
     this.IsGhost = true;
   }
 
-  public IOrigin NavigationToken => RangeToken.StartToken;
+  public IOrigin NavigationToken => Origin.StartToken;
   public bool IsTypeExplicit { get; }
   public override IEnumerable<INode> Children =>
     Attributes.AsEnumerable().
diff --git a/Source/DafnyCore/AST/Statements/Assignment/SingleAssignStmt.cs b/Source/DafnyCore/AST/Statements/Assignment/SingleAssignStmt.cs
index 561b682afda..b91fb9f76a0 100644
--- a/Source/DafnyCore/AST/Statements/Assignment/SingleAssignStmt.cs
+++ b/Source/DafnyCore/AST/Statements/Assignment/SingleAssignStmt.cs
@@ -20,22 +20,6 @@ void ObjectInvariant() {
     Contract.Invariant(Rhs != null);
   }
 
-  public override IOrigin Tok {
-    get {
-      if (Rhs.StartToken.Prev is not null) {
-        var previous = Rhs.StartToken.Prev;
-        // If there was a single assignment, report on the operator.
-        var singleAssignment = previous.val == ":=";
-        // If there was an implicit return assignment, report on the return.
-        var implicitAssignment = previous.val == "return";
-        if (singleAssignment || implicitAssignment) {
-          return previous;
-        }
-      }
-      return Rhs.StartToken;
-    }
-  }
-
   public SingleAssignStmt Clone(Cloner cloner) {
     return new SingleAssignStmt(cloner, this);
   }
@@ -45,7 +29,7 @@ public SingleAssignStmt(Cloner cloner, SingleAssignStmt original) : base(cloner,
     Rhs = cloner.CloneRHS(original.Rhs);
   }
 
-  public SingleAssignStmt(RangeToken rangeOrigin, Expression lhs, AssignmentRhs rhs)
+  public SingleAssignStmt(IOrigin rangeOrigin, Expression lhs, AssignmentRhs rhs)
     : base(rangeOrigin) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(lhs != null);
diff --git a/Source/DafnyCore/AST/Statements/Assignment/VarDeclPattern.cs b/Source/DafnyCore/AST/Statements/Assignment/VarDeclPattern.cs
index 0f3fa4d9e02..dd7f5b5c8e9 100644
--- a/Source/DafnyCore/AST/Statements/Assignment/VarDeclPattern.cs
+++ b/Source/DafnyCore/AST/Statements/Assignment/VarDeclPattern.cs
@@ -18,7 +18,7 @@ public VarDeclPattern(Cloner cloner, VarDeclPattern original) : base(cloner, ori
     HasGhostModifier = original.HasGhostModifier;
   }
 
-  public VarDeclPattern(RangeToken rangeOrigin, CasePattern<LocalVariable> lhs, Expression rhs, bool hasGhostModifier)
+  public VarDeclPattern(IOrigin rangeOrigin, CasePattern<LocalVariable> lhs, Expression rhs, bool hasGhostModifier)
     : base(rangeOrigin) {
     LHS = lhs;
     RHS = rhs;
diff --git a/Source/DafnyCore/AST/Statements/Assignment/VarDeclStmt.cs b/Source/DafnyCore/AST/Statements/Assignment/VarDeclStmt.cs
index fa66707919c..9cea53053c1 100644
--- a/Source/DafnyCore/AST/Statements/Assignment/VarDeclStmt.cs
+++ b/Source/DafnyCore/AST/Statements/Assignment/VarDeclStmt.cs
@@ -22,7 +22,7 @@ public VarDeclStmt(Cloner cloner, VarDeclStmt original) : base(cloner, original)
     Assign = (ConcreteAssignStatement)cloner.CloneStmt(original.Assign, false);
   }
 
-  public VarDeclStmt(RangeToken rangeOrigin, List<LocalVariable> locals, ConcreteAssignStatement assign)
+  public VarDeclStmt(IOrigin rangeOrigin, List<LocalVariable> locals, ConcreteAssignStatement assign)
     : base(rangeOrigin) {
     Contract.Requires(locals != null);
     Contract.Requires(locals.Count != 0);
diff --git a/Source/DafnyCore/AST/Statements/BlockByProofStmt.cs b/Source/DafnyCore/AST/Statements/BlockByProofStmt.cs
index 09f0489dce3..ebade64175a 100644
--- a/Source/DafnyCore/AST/Statements/BlockByProofStmt.cs
+++ b/Source/DafnyCore/AST/Statements/BlockByProofStmt.cs
@@ -9,7 +9,7 @@ public class BlockByProofStmt : Statement, ICanResolveNewAndOld, ICanPrint,
 
   public Statement Body { get; }
   public BlockStmt Proof { get; }
-  public BlockByProofStmt(RangeToken range, BlockStmt proof, Statement body) : base(range) {
+  public BlockByProofStmt(IOrigin range, BlockStmt proof, Statement body) : base(range) {
     Proof = proof;
     Body = body;
   }
diff --git a/Source/DafnyCore/AST/Statements/BlockStmt.cs b/Source/DafnyCore/AST/Statements/BlockStmt.cs
index 7ddef002368..ccc4f293734 100644
--- a/Source/DafnyCore/AST/Statements/BlockStmt.cs
+++ b/Source/DafnyCore/AST/Statements/BlockStmt.cs
@@ -15,7 +15,7 @@ protected BlockStmt(Cloner cloner, BlockStmt original) : base(cloner, original)
     Body = original.Body.Select(stmt => cloner.CloneStmt(stmt, false)).ToList();
   }
 
-  public BlockStmt(RangeToken rangeOrigin, [Captured] List<Statement> body)
+  public BlockStmt(IOrigin rangeOrigin, [Captured] List<Statement> body)
     : base(rangeOrigin) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(cce.NonNullElements(body));
diff --git a/Source/DafnyCore/AST/Statements/CalcStmt.cs b/Source/DafnyCore/AST/Statements/CalcStmt.cs
index b28d3e3e6de..36312ea1c06 100644
--- a/Source/DafnyCore/AST/Statements/CalcStmt.cs
+++ b/Source/DafnyCore/AST/Statements/CalcStmt.cs
@@ -223,7 +223,7 @@ void ObjectInvariant() {
     Contract.Invariant(StepOps.Count == Hints.Count);
   }
 
-  public CalcStmt(RangeToken rangeOrigin, CalcOp userSuppliedOp, List<Expression> lines, List<BlockStmt> hints, List<CalcOp/*?*/> stepOps, Attributes attrs)
+  public CalcStmt(IOrigin rangeOrigin, CalcOp userSuppliedOp, List<Expression> lines, List<BlockStmt> hints, List<CalcOp/*?*/> stepOps, Attributes attrs)
     : base(rangeOrigin) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(lines != null);
diff --git a/Source/DafnyCore/AST/Statements/ControlFlow/AlternativeLoopStmt.cs b/Source/DafnyCore/AST/Statements/ControlFlow/AlternativeLoopStmt.cs
index fc88b91929d..fcbf6fb60b9 100644
--- a/Source/DafnyCore/AST/Statements/ControlFlow/AlternativeLoopStmt.cs
+++ b/Source/DafnyCore/AST/Statements/ControlFlow/AlternativeLoopStmt.cs
@@ -21,7 +21,7 @@ public AlternativeLoopStmt(Cloner cloner, AlternativeLoopStmt original) : base(c
     UsesOptionalBraces = original.UsesOptionalBraces;
   }
 
-  public AlternativeLoopStmt(RangeToken rangeOrigin,
+  public AlternativeLoopStmt(IOrigin rangeOrigin,
     List<AttributedExpression> invariants, Specification<Expression> decreases, Specification<FrameExpression> mod,
     List<GuardedAlternative> alternatives, bool usesOptionalBraces)
     : base(rangeOrigin, invariants, decreases, mod) {
@@ -29,7 +29,7 @@ public AlternativeLoopStmt(RangeToken rangeOrigin,
     this.Alternatives = alternatives;
     this.UsesOptionalBraces = usesOptionalBraces;
   }
-  public AlternativeLoopStmt(RangeToken rangeOrigin,
+  public AlternativeLoopStmt(IOrigin rangeOrigin,
     List<AttributedExpression> invariants, Specification<Expression> decreases, Specification<FrameExpression> mod,
     List<GuardedAlternative> alternatives, bool usesOptionalBraces, Attributes attrs)
     : base(rangeOrigin, invariants, decreases, mod, attrs) {
diff --git a/Source/DafnyCore/AST/Statements/ControlFlow/AlternativeStmt.cs b/Source/DafnyCore/AST/Statements/ControlFlow/AlternativeStmt.cs
index d26e6dcb867..c1425cd3259 100644
--- a/Source/DafnyCore/AST/Statements/ControlFlow/AlternativeStmt.cs
+++ b/Source/DafnyCore/AST/Statements/ControlFlow/AlternativeStmt.cs
@@ -21,7 +21,7 @@ public AlternativeStmt(Cloner cloner, AlternativeStmt original) : base(cloner, o
     UsesOptionalBraces = original.UsesOptionalBraces;
   }
 
-  public AlternativeStmt(RangeToken rangeOrigin, List<GuardedAlternative> alternatives, bool usesOptionalBraces)
+  public AlternativeStmt(IOrigin rangeOrigin, List<GuardedAlternative> alternatives, bool usesOptionalBraces)
     : base(rangeOrigin) {
     Contract.Requires(alternatives != null);
     Alternatives = alternatives;
diff --git a/Source/DafnyCore/AST/Statements/ControlFlow/BreakOrContinueStmt.cs b/Source/DafnyCore/AST/Statements/ControlFlow/BreakOrContinueStmt.cs
index 931a618e7e4..5f2a031d41c 100644
--- a/Source/DafnyCore/AST/Statements/ControlFlow/BreakOrContinueStmt.cs
+++ b/Source/DafnyCore/AST/Statements/ControlFlow/BreakOrContinueStmt.cs
@@ -31,7 +31,7 @@ public BreakOrContinueStmt(Cloner cloner, BreakOrContinueStmt original) : base(c
     }
   }
 
-  public BreakOrContinueStmt(RangeToken rangeOrigin, IOrigin targetLabel, bool isContinue, Attributes attributes = null)
+  public BreakOrContinueStmt(IOrigin rangeOrigin, IOrigin targetLabel, bool isContinue, Attributes attributes = null)
     : base(rangeOrigin, attributes) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(targetLabel != null);
@@ -43,7 +43,7 @@ public BreakOrContinueStmt(RangeToken rangeOrigin, IOrigin targetLabel, bool isC
   /// For "isContinue == false", represents the statement "break ^breakAndContinueCount ;".
   /// For "isContinue == true", represents the statement "break ^(breakAndContinueCount - 1) continue;".
   /// </summary>
-  public BreakOrContinueStmt(RangeToken rangeOrigin, int breakAndContinueCount, bool isContinue, Attributes attributes = null)
+  public BreakOrContinueStmt(IOrigin rangeOrigin, int breakAndContinueCount, bool isContinue, Attributes attributes = null)
     : base(rangeOrigin, attributes) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(1 <= breakAndContinueCount);
diff --git a/Source/DafnyCore/AST/Statements/ControlFlow/ForLoopStmt.cs b/Source/DafnyCore/AST/Statements/ControlFlow/ForLoopStmt.cs
index 0581daa34c9..cd1d06d2c08 100644
--- a/Source/DafnyCore/AST/Statements/ControlFlow/ForLoopStmt.cs
+++ b/Source/DafnyCore/AST/Statements/ControlFlow/ForLoopStmt.cs
@@ -20,7 +20,7 @@ public ForLoopStmt(Cloner cloner, ForLoopStmt original) : base(cloner, original)
     GoingUp = original.GoingUp;
   }
 
-  public ForLoopStmt(RangeToken rangeOrigin, BoundVar loopIndexVariable, Expression start, Expression/*?*/ end, bool goingUp,
+  public ForLoopStmt(IOrigin rangeOrigin, BoundVar loopIndexVariable, Expression start, Expression/*?*/ end, bool goingUp,
     List<AttributedExpression> invariants, Specification<Expression> decreases, Specification<FrameExpression> mod,
     BlockStmt /*?*/ body, Attributes attrs)
     : base(rangeOrigin, invariants, decreases, mod, body, attrs) {
diff --git a/Source/DafnyCore/AST/Statements/ControlFlow/ForallStmt.cs b/Source/DafnyCore/AST/Statements/ControlFlow/ForallStmt.cs
index 651af155f8d..c050c40163e 100644
--- a/Source/DafnyCore/AST/Statements/ControlFlow/ForallStmt.cs
+++ b/Source/DafnyCore/AST/Statements/ControlFlow/ForallStmt.cs
@@ -63,7 +63,7 @@ public ForallStmt(Cloner cloner, ForallStmt original) : base(cloner, original) {
     }
   }
 
-  public ForallStmt(RangeToken rangeOrigin, List<BoundVar> boundVars, Attributes attrs, Expression range, List<AttributedExpression> ens, Statement body)
+  public ForallStmt(IOrigin rangeOrigin, List<BoundVar> boundVars, Attributes attrs, Expression range, List<AttributedExpression> ens, Statement body)
     : base(rangeOrigin, attrs) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(cce.NonNullElements(boundVars));
diff --git a/Source/DafnyCore/AST/Statements/ControlFlow/IfStmt.cs b/Source/DafnyCore/AST/Statements/ControlFlow/IfStmt.cs
index d3eddc5274e..6476299dcec 100644
--- a/Source/DafnyCore/AST/Statements/ControlFlow/IfStmt.cs
+++ b/Source/DafnyCore/AST/Statements/ControlFlow/IfStmt.cs
@@ -26,7 +26,7 @@ public IfStmt(Cloner cloner, IfStmt original) : base(cloner, original) {
     Els = cloner.CloneStmt(original.Els, false);
   }
 
-  public IfStmt(RangeToken rangeOrigin, bool isBindingGuard, Expression guard, BlockStmt thn, Statement els)
+  public IfStmt(IOrigin rangeOrigin, bool isBindingGuard, Expression guard, BlockStmt thn, Statement els)
     : base(rangeOrigin) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(!isBindingGuard || (guard is ExistsExpr && ((ExistsExpr)guard).Range == null));
@@ -37,7 +37,7 @@ public IfStmt(RangeToken rangeOrigin, bool isBindingGuard, Expression guard, Blo
     Thn = thn;
     Els = els;
   }
-  public IfStmt(RangeToken rangeOrigin, bool isBindingGuard, Expression guard, BlockStmt thn, Statement els, Attributes attrs)
+  public IfStmt(IOrigin rangeOrigin, bool isBindingGuard, Expression guard, BlockStmt thn, Statement els, Attributes attrs)
     : base(rangeOrigin, attrs) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(!isBindingGuard || (guard is ExistsExpr && ((ExistsExpr)guard).Range == null));
diff --git a/Source/DafnyCore/AST/Statements/ControlFlow/LoopStmt.cs b/Source/DafnyCore/AST/Statements/ControlFlow/LoopStmt.cs
index 87ed107ad3c..99c1f0e3f4a 100644
--- a/Source/DafnyCore/AST/Statements/ControlFlow/LoopStmt.cs
+++ b/Source/DafnyCore/AST/Statements/ControlFlow/LoopStmt.cs
@@ -26,7 +26,7 @@ protected LoopStmt(Cloner cloner, LoopStmt original) : base(cloner, original) {
     }
   }
 
-  public LoopStmt(RangeToken rangeOrigin, List<AttributedExpression> invariants, Specification<Expression> decreases, Specification<FrameExpression> mod)
+  protected LoopStmt(IOrigin rangeOrigin, List<AttributedExpression> invariants, Specification<Expression> decreases, Specification<FrameExpression> mod)
     : base(rangeOrigin) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(cce.NonNullElements(invariants));
@@ -37,7 +37,8 @@ public LoopStmt(RangeToken rangeOrigin, List<AttributedExpression> invariants, S
     this.Decreases = decreases;
     this.Mod = mod;
   }
-  public LoopStmt(RangeToken rangeOrigin, List<AttributedExpression> invariants, Specification<Expression> decreases, Specification<FrameExpression> mod, Attributes attrs)
+
+  protected LoopStmt(IOrigin rangeOrigin, List<AttributedExpression> invariants, Specification<Expression> decreases, Specification<FrameExpression> mod, Attributes attrs)
     : base(rangeOrigin, attrs) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(cce.NonNullElements(invariants));
@@ -85,5 +86,5 @@ public override IEnumerable<Expression> SpecificationSubExpressions {
     }
   }
 
-  public IOrigin NavigationToken => Tok;
+  public IOrigin NavigationToken => Center;
 }
\ No newline at end of file
diff --git a/Source/DafnyCore/AST/Statements/ControlFlow/OneBodyLoopStmt.cs b/Source/DafnyCore/AST/Statements/ControlFlow/OneBodyLoopStmt.cs
index 41995a926a8..9d15140f315 100644
--- a/Source/DafnyCore/AST/Statements/ControlFlow/OneBodyLoopStmt.cs
+++ b/Source/DafnyCore/AST/Statements/ControlFlow/OneBodyLoopStmt.cs
@@ -21,7 +21,7 @@ protected OneBodyLoopStmt(Cloner cloner, OneBodyLoopStmt original) : base(cloner
     }
   }
 
-  protected OneBodyLoopStmt(RangeToken rangeOrigin,
+  protected OneBodyLoopStmt(IOrigin rangeOrigin,
     List<AttributedExpression> invariants, Specification<Expression> decreases, Specification<FrameExpression> mod,
     BlockStmt /*?*/ body, Attributes/*?*/ attrs)
     : base(rangeOrigin, invariants, decreases, mod, attrs) {
diff --git a/Source/DafnyCore/AST/Statements/ControlFlow/RefinedWhileStmt.cs b/Source/DafnyCore/AST/Statements/ControlFlow/RefinedWhileStmt.cs
index 6f06497e28c..d8a4127bcf9 100644
--- a/Source/DafnyCore/AST/Statements/ControlFlow/RefinedWhileStmt.cs
+++ b/Source/DafnyCore/AST/Statements/ControlFlow/RefinedWhileStmt.cs
@@ -8,7 +8,7 @@ namespace Microsoft.Dafny;
 /// merge.
 /// </summary>
 public class RefinedWhileStmt : WhileStmt {
-  public RefinedWhileStmt(RangeToken rangeOrigin, Expression guard,
+  public RefinedWhileStmt(IOrigin rangeOrigin, Expression guard,
     List<AttributedExpression> invariants, Specification<Expression> decreases, Specification<FrameExpression> mod,
     BlockStmt body)
     : base(rangeOrigin, guard, invariants, decreases, mod, body) {
diff --git a/Source/DafnyCore/AST/Statements/ControlFlow/WhileStmt.cs b/Source/DafnyCore/AST/Statements/ControlFlow/WhileStmt.cs
index 3a8a0693896..4c6b68abf82 100644
--- a/Source/DafnyCore/AST/Statements/ControlFlow/WhileStmt.cs
+++ b/Source/DafnyCore/AST/Statements/ControlFlow/WhileStmt.cs
@@ -23,14 +23,14 @@ public WhileStmt(Cloner cloner, WhileStmt original) : base(cloner, original) {
     Guard = cloner.CloneExpr(original.Guard);
   }
 
-  public WhileStmt(RangeToken rangeOrigin, Expression guard,
+  public WhileStmt(IOrigin rangeOrigin, Expression guard,
     List<AttributedExpression> invariants, Specification<Expression> decreases, Specification<FrameExpression> mod,
     BlockStmt body)
     : base(rangeOrigin, invariants, decreases, mod, body, null) {
     Guard = guard;
   }
 
-  public WhileStmt(RangeToken rangeOrigin, Expression guard,
+  public WhileStmt(IOrigin rangeOrigin, Expression guard,
     List<AttributedExpression> invariants, Specification<Expression> decreases, Specification<FrameExpression> mod,
     BlockStmt body, Attributes attrs)
     : base(rangeOrigin, invariants, decreases, mod, body, attrs) {
diff --git a/Source/DafnyCore/AST/Statements/DividedBlockStmt.cs b/Source/DafnyCore/AST/Statements/DividedBlockStmt.cs
index 3d7b3b3f815..6f643a1ce25 100644
--- a/Source/DafnyCore/AST/Statements/DividedBlockStmt.cs
+++ b/Source/DafnyCore/AST/Statements/DividedBlockStmt.cs
@@ -22,7 +22,7 @@ public DividedBlockStmt(Cloner cloner, DividedBlockStmt original) : base(cloner,
     SeparatorTok = original.SeparatorTok;
   }
 
-  public DividedBlockStmt(RangeToken rangeOrigin, List<Statement> bodyInit, IOrigin/*?*/ separatorTok, List<Statement> bodyProper)
+  public DividedBlockStmt(IOrigin rangeOrigin, List<Statement> bodyInit, IOrigin/*?*/ separatorTok, List<Statement> bodyProper)
     : base(rangeOrigin, Util.Concat(bodyInit, bodyProper)) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(cce.NonNullElements(bodyInit));
diff --git a/Source/DafnyCore/AST/Statements/Methods/CallStmt.cs b/Source/DafnyCore/AST/Statements/Methods/CallStmt.cs
index f8b0952ec1e..8c29b026e55 100644
--- a/Source/DafnyCore/AST/Statements/Methods/CallStmt.cs
+++ b/Source/DafnyCore/AST/Statements/Methods/CallStmt.cs
@@ -33,7 +33,7 @@ public override IEnumerable<IdentifierExpr> GetAssignedLocals() {
   public Expression Receiver => MethodSelect.Obj;
   public Method Method => (Method)MethodSelect.Member;
 
-  public CallStmt(RangeToken rangeOrigin, List<Expression> lhs, MemberSelectExpr memSel, List<ActualBinding> args, IOrigin overrideToken = null)
+  public CallStmt(IOrigin rangeOrigin, List<Expression> lhs, MemberSelectExpr memSel, List<ActualBinding> args, IOrigin overrideToken = null)
     : base(rangeOrigin) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(cce.NonNullElements(lhs));
@@ -62,7 +62,7 @@ public CallStmt(Cloner cloner, CallStmt original) : base(cloner, original) {
   /// This constructor is intended to be used when constructing a resolved CallStmt. The "args" are expected
   /// to be already resolved, and are all given positionally.
   /// </summary>
-  public CallStmt(RangeToken rangeOrigin, List<Expression> lhs, MemberSelectExpr memSel, List<Expression> args)
+  public CallStmt(IOrigin rangeOrigin, List<Expression> lhs, MemberSelectExpr memSel, List<Expression> args)
     : this(rangeOrigin, lhs, memSel, args.ConvertAll(e => new ActualBinding(null, e))) {
     Bindings.AcceptArgumentExpressionsAsExactParameterList();
   }
diff --git a/Source/DafnyCore/AST/Statements/Methods/PrintStmt.cs b/Source/DafnyCore/AST/Statements/Methods/PrintStmt.cs
index 5ac850414c7..15f92816a13 100644
--- a/Source/DafnyCore/AST/Statements/Methods/PrintStmt.cs
+++ b/Source/DafnyCore/AST/Statements/Methods/PrintStmt.cs
@@ -33,7 +33,7 @@ public PrintStmt(Cloner cloner, PrintStmt original) : base(cloner, original) {
     Args = original.Args.Select(cloner.CloneExpr).ToList();
   }
 
-  public PrintStmt(RangeToken rangeOrigin, List<Expression> args)
+  public PrintStmt(IOrigin rangeOrigin, List<Expression> args)
     : base(rangeOrigin) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(cce.NonNullElements(args));
diff --git a/Source/DafnyCore/AST/Statements/Methods/ProduceStmt.cs b/Source/DafnyCore/AST/Statements/Methods/ProduceStmt.cs
index 4a05e91e1d4..28e012f2b11 100644
--- a/Source/DafnyCore/AST/Statements/Methods/ProduceStmt.cs
+++ b/Source/DafnyCore/AST/Statements/Methods/ProduceStmt.cs
@@ -19,7 +19,7 @@ protected ProduceStmt(Cloner cloner, ProduceStmt original) : base(cloner, origin
     }
   }
 
-  protected ProduceStmt(RangeToken rangeOrigin, List<AssignmentRhs> rhss, Attributes attributes)
+  protected ProduceStmt(IOrigin rangeOrigin, List<AssignmentRhs> rhss, Attributes attributes)
     : base(rangeOrigin, attributes) {
     this.Rhss = rhss;
     HiddenUpdate = null;
diff --git a/Source/DafnyCore/AST/Statements/Methods/ReturnStmt.cs b/Source/DafnyCore/AST/Statements/Methods/ReturnStmt.cs
index d188c10d3ce..e6eb0612921 100644
--- a/Source/DafnyCore/AST/Statements/Methods/ReturnStmt.cs
+++ b/Source/DafnyCore/AST/Statements/Methods/ReturnStmt.cs
@@ -14,7 +14,7 @@ public ReturnStmt(Cloner cloner, ReturnStmt original) : base(cloner, original) {
     ReverifyPost = original.ReverifyPost;
   }
 
-  public ReturnStmt(RangeToken rangeOrigin, List<AssignmentRhs> rhss, Attributes attributes = null)
+  public ReturnStmt(IOrigin rangeOrigin, List<AssignmentRhs> rhss, Attributes attributes = null)
     : base(rangeOrigin, rhss, attributes) {
     Contract.Requires(rangeOrigin != null);
   }
diff --git a/Source/DafnyCore/AST/Statements/Methods/YieldStmt.cs b/Source/DafnyCore/AST/Statements/Methods/YieldStmt.cs
index dd6a3b38e59..cd3d566111a 100644
--- a/Source/DafnyCore/AST/Statements/Methods/YieldStmt.cs
+++ b/Source/DafnyCore/AST/Statements/Methods/YieldStmt.cs
@@ -10,7 +10,7 @@ public YieldStmt Clone(Cloner cloner) {
   public YieldStmt(Cloner cloner, YieldStmt original) : base(cloner, original) {
   }
 
-  public YieldStmt(RangeToken rangeOrigin, List<AssignmentRhs> rhss)
+  public YieldStmt(IOrigin rangeOrigin, List<AssignmentRhs> rhss)
     : base(rangeOrigin, rhss, null) {
   }
 
diff --git a/Source/DafnyCore/AST/Statements/SkeletonStatement.cs b/Source/DafnyCore/AST/Statements/SkeletonStatement.cs
index e48bcab717a..eb7d99baa0b 100644
--- a/Source/DafnyCore/AST/Statements/SkeletonStatement.cs
+++ b/Source/DafnyCore/AST/Statements/SkeletonStatement.cs
@@ -48,7 +48,7 @@ public SkeletonStatement(RangeToken rangeOrigin)
     S = null;
   }
   public SkeletonStatement(Statement s, IOrigin conditionEllipsis, IOrigin bodyEllipsis)
-    : base(s.RangeToken) {
+    : base(s.Origin) {
     Contract.Requires(s != null);
     S = s;
     ConditionEllipsis = conditionEllipsis;
diff --git a/Source/DafnyCore/AST/Statements/Statement.cs b/Source/DafnyCore/AST/Statements/Statement.cs
index 282b8c92c81..ea6aec4cd48 100644
--- a/Source/DafnyCore/AST/Statements/Statement.cs
+++ b/Source/DafnyCore/AST/Statements/Statement.cs
@@ -6,7 +6,7 @@
 namespace Microsoft.Dafny;
 
 public abstract class Statement : RangeNode, IAttributeBearingDeclaration {
-  public override IOrigin Tok => PostLabelToken ?? StartToken;
+  public override IOrigin Tok => PostLabelToken ?? Origin;
   public IOrigin PostLabelToken { get; set; }
 
   public int ScopeDepth { get; set; }
@@ -26,7 +26,7 @@ public virtual void GenResolve(INewOrOldResolver resolver, ResolutionContext res
     resolver.ResolveAttributes(this, resolutionContext);
   }
 
-  protected Statement(Cloner cloner, Statement original) : base(cloner.Tok(original.RangeToken)) {
+  protected Statement(Cloner cloner, Statement original) : base(cloner.Origin(original.Origin)) {
     cloner.AddStatementClone(original, this);
     this.Attributes = cloner.CloneAttributes(original.Attributes);
 
@@ -36,11 +36,11 @@ protected Statement(Cloner cloner, Statement original) : base(cloner.Tok(origina
     }
   }
 
-  protected Statement(RangeToken rangeOrigin, Attributes attrs) : base(rangeOrigin) {
+  protected Statement(IOrigin rangeOrigin, Attributes attrs) : base(rangeOrigin) {
     this.Attributes = attrs;
   }
 
-  protected Statement(RangeToken rangeOrigin)
+  protected Statement(IOrigin rangeOrigin)
     : this(rangeOrigin, null) {
     Contract.Requires(rangeOrigin != null);
   }
@@ -138,36 +138,34 @@ public virtual IEnumerable<Expression> NonSpecificationSubExpressions {
   /// <summary>
   /// Create a resolved statement for an uninitialized local variable.
   /// </summary>
-  public static VarDeclStmt CreateLocalVariable(IOrigin tok, string name, Type type) {
-    Contract.Requires(tok != null);
+  public static VarDeclStmt CreateLocalVariable(IOrigin origin, string name, Type type) {
+    Contract.Requires(origin != null);
     Contract.Requires(name != null);
     Contract.Requires(type != null);
-    var variable = new LocalVariable(tok.ToRange(), name, type, false);
+    var variable = new LocalVariable(origin, name, type, false);
     variable.type = type;
-    return new VarDeclStmt(tok.ToRange(), Util.Singleton(variable), null);
+    return new VarDeclStmt(origin, Util.Singleton(variable), null);
   }
 
   /// <summary>
   /// Create a resolved statement for a local variable with an initial value.
   /// </summary>
-  public static VarDeclStmt CreateLocalVariable(IOrigin tok, string name, Expression value) {
-    Contract.Requires(tok != null);
+  public static VarDeclStmt CreateLocalVariable(IOrigin origin, string name, Expression value) {
+    Contract.Requires(origin != null);
     Contract.Requires(name != null);
     Contract.Requires(value != null);
-    var rangeToken = new RangeToken(tok, tok);
-    var variable = new LocalVariable(rangeToken, name, value.Type, false);
+    var variable = new LocalVariable(origin, name, value.Type, false);
     variable.type = value.Type;
-    Expression variableExpr = new IdentifierExpr(tok, variable);
-    var variableUpdateStmt = new AssignStatement(rangeToken, Util.Singleton(variableExpr),
+    Expression variableExpr = new IdentifierExpr(origin, variable);
+    var variableUpdateStmt = new AssignStatement(origin, Util.Singleton(variableExpr),
       Util.Singleton<AssignmentRhs>(new ExprRhs(value)));
-    var variableAssignStmt = new SingleAssignStmt(rangeToken, variableUpdateStmt.Lhss[0], variableUpdateStmt.Rhss[0]);
+    var variableAssignStmt = new SingleAssignStmt(origin, variableUpdateStmt.Lhss[0], variableUpdateStmt.Rhss[0]);
     variableUpdateStmt.ResolvedStatements = new List<Statement>() { variableAssignStmt };
-    return new VarDeclStmt(rangeToken, Util.Singleton(variable), variableUpdateStmt);
+    return new VarDeclStmt(origin, Util.Singleton(variable), variableUpdateStmt);
   }
 
   public static PrintStmt CreatePrintStmt(IOrigin tok, params Expression[] exprs) {
-    var rangeToken = new RangeToken(tok, tok);
-    return new PrintStmt(rangeToken, exprs.ToList());
+    return new PrintStmt(tok, exprs.ToList());
   }
 
   public override string ToString() {
diff --git a/Source/DafnyCore/AST/Statements/Verification/AssertStmt.cs b/Source/DafnyCore/AST/Statements/Verification/AssertStmt.cs
index 497a9af0b1e..aa2c4a542d8 100644
--- a/Source/DafnyCore/AST/Statements/Verification/AssertStmt.cs
+++ b/Source/DafnyCore/AST/Statements/Verification/AssertStmt.cs
@@ -12,7 +12,7 @@ public AssertStmt Clone(Cloner cloner) {
   }
 
   public AssertStmt(Cloner cloner, AssertStmt original) : base(cloner, original) {
-    Label = original.Label == null ? null : new AssertLabel(cloner.Tok(original.Label.Tok), original.Label.Name);
+    Label = original.Label == null ? null : new AssertLabel(cloner.Origin(original.Label.Tok), original.Label.Name);
   }
 
   public static AssertStmt CreateErrorAssert(INode node, string message, Expression guard = null) {
@@ -20,12 +20,12 @@ public static AssertStmt CreateErrorAssert(INode node, string message, Expressio
     errorMessage.Type = new SeqType(Type.Char);
     var attr = new Attributes("error", new List<Expression> { errorMessage }, null);
     guard ??= Expression.CreateBoolLiteral(node.Tok, false);
-    var assertFalse = new AssertStmt(node.RangeToken, guard, null, attr);
+    var assertFalse = new AssertStmt(node.Origin, guard, null, attr);
     assertFalse.IsGhost = true;
     return assertFalse;
   }
 
-  public AssertStmt(RangeToken rangeOrigin, Expression expr, AssertLabel/*?*/ label, Attributes attrs)
+  public AssertStmt(IOrigin rangeOrigin, Expression expr, AssertLabel/*?*/ label, Attributes attrs)
     : base(rangeOrigin, expr, attrs) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(expr != null);
@@ -67,12 +67,12 @@ public override void GenResolve(INewOrOldResolver resolver, ResolutionContext co
     }
 
     if (this.HasUserAttribute("only", out var attribute)) {
-      resolver.Reporter.Warning(MessageSource.Verifier, ResolutionErrors.ErrorId.r_assert_only_assumes_others.ToString(), attribute.RangeToken.ToToken(),
+      resolver.Reporter.Warning(MessageSource.Verifier, ResolutionErrors.ErrorId.r_assert_only_assumes_others.ToString(), attribute.Origin,
         "Assertion with {:only} temporarily transforms other assertions into assumptions");
       if (attribute.Args.Count >= 1
           && attribute.Args[0] is LiteralExpr { Value: string value }
           && value != "before" && value != "after") {
-        resolver.Reporter.Warning(MessageSource.Verifier, ResolutionErrors.ErrorId.r_assert_only_before_after.ToString(), attribute.Args[0].RangeToken.ToToken(),
+        resolver.Reporter.Warning(MessageSource.Verifier, ResolutionErrors.ErrorId.r_assert_only_before_after.ToString(), attribute.Args[0].Origin,
           "{:only} only accepts \"before\" or \"after\" as an optional argument");
       }
     }
diff --git a/Source/DafnyCore/AST/Statements/Verification/AssumeStmt.cs b/Source/DafnyCore/AST/Statements/Verification/AssumeStmt.cs
index 688e90052a8..d19e6bcaf71 100644
--- a/Source/DafnyCore/AST/Statements/Verification/AssumeStmt.cs
+++ b/Source/DafnyCore/AST/Statements/Verification/AssumeStmt.cs
@@ -12,7 +12,7 @@ public AssumeStmt Clone(Cloner cloner) {
   public AssumeStmt(Cloner cloner, AssumeStmt original) : base(cloner, original) {
   }
 
-  public AssumeStmt(RangeToken rangeOrigin, Expression expr, Attributes attrs)
+  public AssumeStmt(IOrigin rangeOrigin, Expression expr, Attributes attrs)
     : base(rangeOrigin, expr, attrs) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(expr != null);
diff --git a/Source/DafnyCore/AST/Statements/Verification/ExpectStmt.cs b/Source/DafnyCore/AST/Statements/Verification/ExpectStmt.cs
index 18ee1402e59..ac944983c00 100644
--- a/Source/DafnyCore/AST/Statements/Verification/ExpectStmt.cs
+++ b/Source/DafnyCore/AST/Statements/Verification/ExpectStmt.cs
@@ -16,7 +16,7 @@ public ExpectStmt(Cloner cloner, ExpectStmt original) : base(cloner, original) {
     Message = cloner.CloneExpr(original.Message);
   }
 
-  public ExpectStmt(RangeToken rangeOrigin, Expression expr, Expression message, Attributes attrs)
+  public ExpectStmt(IOrigin rangeOrigin, Expression expr, Expression message, Attributes attrs)
     : base(rangeOrigin, expr, attrs) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(expr != null);
diff --git a/Source/DafnyCore/AST/Statements/Verification/HideRevealStmt.cs b/Source/DafnyCore/AST/Statements/Verification/HideRevealStmt.cs
index 9d643bb3a47..39e5b9cde32 100644
--- a/Source/DafnyCore/AST/Statements/Verification/HideRevealStmt.cs
+++ b/Source/DafnyCore/AST/Statements/Verification/HideRevealStmt.cs
@@ -39,19 +39,19 @@ public HideRevealStmt(Cloner cloner, HideRevealStmt original) : base(cloner, ori
     Wildcard = original.Wildcard;
     if (cloner.CloneResolvedFields) {
       OffsetMembers = original.OffsetMembers.ToList();
-      LabeledAsserts = original.LabeledAsserts.Select(a => new AssertLabel(cloner.Tok(a.Tok), a.Name)).ToList();
+      LabeledAsserts = original.LabeledAsserts.Select(a => new AssertLabel(cloner.Origin(a.Tok), a.Name)).ToList();
       ResolvedStatements = original.ResolvedStatements.Select(stmt => cloner.CloneStmt(stmt, false)).ToList();
     }
   }
 
-  public HideRevealStmt(RangeToken rangeOrigin, HideRevealCmd.Modes mode)
+  public HideRevealStmt(IOrigin rangeOrigin, HideRevealCmd.Modes mode)
     : base(rangeOrigin) {
     Wildcard = true;
     this.Exprs = null;
     Mode = mode;
   }
 
-  public HideRevealStmt(RangeToken rangeOrigin, List<Expression> exprs, HideRevealCmd.Modes mode)
+  public HideRevealStmt(IOrigin rangeOrigin, List<Expression> exprs, HideRevealCmd.Modes mode)
     : base(rangeOrigin) {
     Contract.Requires(exprs != null);
     this.Exprs = exprs;
@@ -121,7 +121,7 @@ public override void GenResolve(INewOrOldResolver resolver, ResolutionContext re
 
               var revealCallee = ((MemberSelectExpr)((ConcreteSyntaxExpression)exprClone).ResolvedExpression);
               if (revealCallee != null) {
-                var call = new CallStmt(RangeToken, new List<Expression>(),
+                var call = new CallStmt(Origin, new List<Expression>(),
                   revealCallee,
                   new List<ActualBinding>(), effectiveExpr.tok);
                 ResolvedStatements.Add(call);
diff --git a/Source/DafnyCore/AST/Statements/Verification/ModifyStmt.cs b/Source/DafnyCore/AST/Statements/Verification/ModifyStmt.cs
index 0ea1d682057..7ac88dee9bb 100644
--- a/Source/DafnyCore/AST/Statements/Verification/ModifyStmt.cs
+++ b/Source/DafnyCore/AST/Statements/Verification/ModifyStmt.cs
@@ -16,7 +16,7 @@ public ModifyStmt(Cloner cloner, ModifyStmt original) : base(cloner, original) {
     Body = cloner.CloneBlockStmt(original.Body);
   }
 
-  public ModifyStmt(RangeToken rangeOrigin, List<FrameExpression> mod, Attributes attrs, BlockStmt body)
+  public ModifyStmt(IOrigin rangeOrigin, List<FrameExpression> mod, Attributes attrs, BlockStmt body)
     : base(rangeOrigin) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(mod != null);
diff --git a/Source/DafnyCore/AST/Statements/Verification/PredicateStmt.cs b/Source/DafnyCore/AST/Statements/Verification/PredicateStmt.cs
index 673cc68aead..c67bade9ddd 100644
--- a/Source/DafnyCore/AST/Statements/Verification/PredicateStmt.cs
+++ b/Source/DafnyCore/AST/Statements/Verification/PredicateStmt.cs
@@ -13,7 +13,7 @@ protected PredicateStmt(Cloner cloner, PredicateStmt original) : base(cloner, or
     Expr = cloner.CloneExpr(original.Expr);
   }
 
-  protected PredicateStmt(RangeToken rangeOrigin, Expression expr, Attributes attrs)
+  protected PredicateStmt(IOrigin rangeOrigin, Expression expr, Attributes attrs)
     : base(rangeOrigin, attrs) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(expr != null);
diff --git a/Source/DafnyCore/AST/Substituter.cs b/Source/DafnyCore/AST/Substituter.cs
index ec4ad6cf9c9..2d1c5b782e5 100644
--- a/Source/DafnyCore/AST/Substituter.cs
+++ b/Source/DafnyCore/AST/Substituter.cs
@@ -62,7 +62,7 @@ public virtual Expression Substitute(Expression expr) {
         } else {
           return new ParensExpression(expr.tok, receiverReplacement) {
             ResolvedExpression = receiverReplacement,
-            RangeToken = expr.RangeToken,
+            RangeOrigin = expr.Origin,
             Type = receiverReplacement.Type
           };
         }
@@ -75,7 +75,7 @@ public virtual Expression Substitute(Expression expr) {
             // clone it, using the source location of the original
             substExprFinal = new IdentifierExpr(expr.tok, substIdExpr.Var);
           } else {
-            if (substExpr.RangeToken != e.RangeToken) {
+            if (substExpr.Origin != e.Origin) {
               var substExprParens = new ParensExpression(expr.tok, substExpr);
               substExprParens.Type = substExpr.Type;
               substExprParens.ResolvedExpression = substExpr;
@@ -400,7 +400,7 @@ ExtendedPattern SubstituteForPattern(ExtendedPattern pattern) {
         var resolvedExpression = Substitute(concreteSyntaxExpression.ResolvedExpression);
         return new ParensExpression(expr.tok, resolvedExpression) {
           ResolvedExpression = resolvedExpression,
-          RangeToken = expr.RangeToken,
+          RangeOrigin = expr.Origin,
           Type = resolvedExpression.Type
         };
 
@@ -609,7 +609,7 @@ protected virtual List<LocalVariable> CreateLocalVarSubstitutions(List<LocalVari
           newVars.Add(v);
         } else {
           anythingChanged = true;
-          var newVar = new LocalVariable(v.RangeToken, v.Name, tt, v.IsGhost);
+          var newVar = new LocalVariable(v.Origin, v.Name, tt, v.IsGhost);
           newVar.type = tt;  // resolve here
           newVars.Add(newVar);
           // update substMap to reflect the new LocalVariable substitutions
@@ -750,7 +750,7 @@ protected List<Type> SubstituteTypeList(List<Type> types) {
     }
 
     public LocalVariable CloneLocalVariable(CasePattern<LocalVariable> pat, Type tt, LocalVariable lv) {
-      return new LocalVariable(pat.RangeToken, pat.Id, tt, lv.IsGhost);
+      return new LocalVariable(pat.Origin, pat.Id, tt, lv.IsGhost);
     }
     public BoundVar CloneBoundVar(CasePattern<BoundVar> pat, Type tt, BoundVar bv) {
       return new BoundVar(pat.tok, pat.Id, tt);
@@ -766,20 +766,20 @@ protected virtual Statement SubstStmt(Statement stmt) {
         return null;
       } else if (stmt is AssertStmt) {
         var s = (AssertStmt)stmt;
-        r = new AssertStmt(s.RangeToken, Substitute(s.Expr), s.Label, SubstAttributes(s.Attributes));
+        r = new AssertStmt(s.Origin, Substitute(s.Expr), s.Label, SubstAttributes(s.Attributes));
       } else if (stmt is ExpectStmt) {
         var s = (ExpectStmt)stmt;
-        r = new ExpectStmt(s.RangeToken, Substitute(s.Expr), Substitute(s.Message), SubstAttributes(s.Attributes));
+        r = new ExpectStmt(s.Origin, Substitute(s.Expr), Substitute(s.Message), SubstAttributes(s.Attributes));
       } else if (stmt is AssumeStmt) {
         var s = (AssumeStmt)stmt;
-        r = new AssumeStmt(s.RangeToken, Substitute(s.Expr), SubstAttributes(s.Attributes));
+        r = new AssumeStmt(s.Origin, Substitute(s.Expr), SubstAttributes(s.Attributes));
       } else if (stmt is BreakOrContinueStmt) {
         var s = (BreakOrContinueStmt)stmt;
         BreakOrContinueStmt rr;
         if (s.TargetLabel != null) {
-          rr = new BreakOrContinueStmt(s.RangeToken, s.TargetLabel, s.IsContinue);
+          rr = new BreakOrContinueStmt(s.Origin, s.TargetLabel, s.IsContinue);
         } else {
-          rr = new BreakOrContinueStmt(s.RangeToken, s.BreakAndContinueCount, s.IsContinue);
+          rr = new BreakOrContinueStmt(s.Origin, s.BreakAndContinueCount, s.IsContinue);
         }
         // r.TargetStmt will be filled in as later
         if (!BreaksToBeResolved.TryGetValue(s, out var breaks)) {
@@ -790,10 +790,10 @@ protected virtual Statement SubstStmt(Statement stmt) {
         r = rr;
       } else if (stmt is SingleAssignStmt) {
         var s = (SingleAssignStmt)stmt;
-        r = new SingleAssignStmt(s.RangeToken, Substitute(s.Lhs), SubstRHS(s.Rhs));
+        r = new SingleAssignStmt(s.Origin, Substitute(s.Lhs), SubstRHS(s.Rhs));
       } else if (stmt is CallStmt) {
         var s = (CallStmt)stmt;
-        var rr = new CallStmt(s.RangeToken, s.Lhs.ConvertAll(Substitute), (MemberSelectExpr)Substitute(s.MethodSelect), s.Args.ConvertAll(Substitute));
+        var rr = new CallStmt(s.Origin, s.Lhs.ConvertAll(Substitute), (MemberSelectExpr)Substitute(s.MethodSelect), s.Args.ConvertAll(Substitute));
         r = rr;
       } else if (stmt is DividedBlockStmt) {
         r = SubstDividedBlockStmt((DividedBlockStmt)stmt);
@@ -802,16 +802,16 @@ protected virtual Statement SubstStmt(Statement stmt) {
       } else if (stmt is IfStmt) {
         var s = (IfStmt)stmt;
         var guard = s.IsBindingGuard ? SubstituteComprehensionExpr((ExistsExpr)s.Guard, false) : Substitute(s.Guard);
-        r = new IfStmt(s.RangeToken, s.IsBindingGuard, guard, SubstBlockStmt(s.Thn), SubstStmt(s.Els));
+        r = new IfStmt(s.Origin, s.IsBindingGuard, guard, SubstBlockStmt(s.Thn), SubstStmt(s.Els));
       } else if (stmt is AlternativeStmt) {
         var s = (AlternativeStmt)stmt;
-        r = new AlternativeStmt(s.RangeToken, s.Alternatives.ConvertAll(SubstGuardedAlternative), s.UsesOptionalBraces);
+        r = new AlternativeStmt(s.Origin, s.Alternatives.ConvertAll(SubstGuardedAlternative), s.UsesOptionalBraces);
       } else if (stmt is WhileStmt) {
         var s = (WhileStmt)stmt;
-        r = new WhileStmt(s.RangeToken, Substitute(s.Guard), s.Invariants.ConvertAll(SubstMayBeFreeExpr), SubstSpecExpr(s.Decreases), SubstSpecFrameExpr(s.Mod), SubstBlockStmt(s.Body));
+        r = new WhileStmt(s.Origin, Substitute(s.Guard), s.Invariants.ConvertAll(SubstMayBeFreeExpr), SubstSpecExpr(s.Decreases), SubstSpecFrameExpr(s.Mod), SubstBlockStmt(s.Body));
       } else if (stmt is AlternativeLoopStmt) {
         var s = (AlternativeLoopStmt)stmt;
-        r = new AlternativeLoopStmt(s.RangeToken, s.Invariants.ConvertAll(SubstMayBeFreeExpr), SubstSpecExpr(s.Decreases), SubstSpecFrameExpr(s.Mod), s.Alternatives.ConvertAll(SubstGuardedAlternative), s.UsesOptionalBraces);
+        r = new AlternativeLoopStmt(s.Origin, s.Invariants.ConvertAll(SubstMayBeFreeExpr), SubstSpecExpr(s.Decreases), SubstSpecFrameExpr(s.Mod), s.Alternatives.ConvertAll(SubstGuardedAlternative), s.UsesOptionalBraces);
       } else if (stmt is ForallStmt) {
         var s = (ForallStmt)stmt;
         var newBoundVars = CreateBoundVarSubstitutions(s.BoundVars, false);
@@ -822,7 +822,7 @@ protected virtual Statement SubstStmt(Statement stmt) {
         }
 
         // Put things together
-        var rr = new ForallStmt(s.RangeToken, newBoundVars, SubstAttributes(s.Attributes), Substitute(s.Range), s.Ens.ConvertAll(SubstMayBeFreeExpr), body);
+        var rr = new ForallStmt(s.Origin, newBoundVars, SubstAttributes(s.Attributes), Substitute(s.Range), s.Ens.ConvertAll(SubstMayBeFreeExpr), body);
         rr.Kind = s.Kind;
         rr.CanConvert = s.CanConvert;
         rr.Bounds = SubstituteBoundedPoolList(s.Bounds);
@@ -832,19 +832,19 @@ protected virtual Statement SubstStmt(Statement stmt) {
         r = rr;
       } else if (stmt is CalcStmt) {
         var s = (CalcStmt)stmt;
-        var rr = new CalcStmt(s.RangeToken, SubstCalcOp(s.UserSuppliedOp), s.Lines.ConvertAll(Substitute), s.Hints.ConvertAll(SubstBlockStmt), s.StepOps.ConvertAll(SubstCalcOp), SubstAttributes(s.Attributes));
+        var rr = new CalcStmt(s.Origin, SubstCalcOp(s.UserSuppliedOp), s.Lines.ConvertAll(Substitute), s.Hints.ConvertAll(SubstBlockStmt), s.StepOps.ConvertAll(SubstCalcOp), SubstAttributes(s.Attributes));
         rr.Op = SubstCalcOp(s.Op);
         rr.Steps.AddRange(s.Steps.ConvertAll(Substitute));
         rr.Result = Substitute(s.Result);
         r = rr;
       } else if (stmt is MatchStmt) {
         var s = (MatchStmt)stmt;
-        var rr = new MatchStmt(s.RangeToken, Substitute(s.Source), s.Cases.ConvertAll(SubstMatchCaseStmt), s.UsesOptionalBraces);
+        var rr = new MatchStmt(s.Origin, Substitute(s.Source), s.Cases.ConvertAll(SubstMatchCaseStmt), s.UsesOptionalBraces);
         rr.MissingCases.AddRange(s.MissingCases);
         r = rr;
       } else if (stmt is AssignSuchThatStmt) {
         var s = (AssignSuchThatStmt)stmt;
-        r = new AssignSuchThatStmt(s.RangeToken, s.Lhss.ConvertAll(Substitute), Substitute(s.Expr), s.AssumeToken, null) {
+        r = new AssignSuchThatStmt(s.Origin, s.Lhss.ConvertAll(Substitute), Substitute(s.Expr), s.AssumeToken, null) {
           Bounds = SubstituteBoundedPoolList(s.Bounds)
         };
       } else if (stmt is AssignStatement) {
@@ -853,9 +853,9 @@ protected virtual Statement SubstStmt(Statement stmt) {
         AssignStatement rr;
         if (resolved.Count == 1) {
           // when later translating this UpdateStmt, the s.Lhss and s.Rhss components won't be used, only s.ResolvedStatements
-          rr = new AssignStatement(s.RangeToken, s.Lhss, s.Rhss, s.CanMutateKnownState);
+          rr = new AssignStatement(s.Origin, s.Lhss, s.Rhss, s.CanMutateKnownState);
         } else {
-          rr = new AssignStatement(s.RangeToken, s.Lhss.ConvertAll(Substitute), s.Rhss.ConvertAll(SubstRHS), s.CanMutateKnownState);
+          rr = new AssignStatement(s.Origin, s.Lhss.ConvertAll(Substitute), s.Rhss.ConvertAll(SubstRHS), s.CanMutateKnownState);
         }
 
         if (s.ResolvedStatements != null) {
@@ -865,24 +865,24 @@ protected virtual Statement SubstStmt(Statement stmt) {
       } else if (stmt is VarDeclStmt) {
         var s = (VarDeclStmt)stmt;
         var lhss = CreateLocalVarSubstitutions(s.Locals, false);
-        var rr = new VarDeclStmt(s.RangeToken, lhss, (ConcreteAssignStatement)SubstStmt(s.Assign));
+        var rr = new VarDeclStmt(s.Origin, lhss, (ConcreteAssignStatement)SubstStmt(s.Assign));
         r = rr;
       } else if (stmt is VarDeclPattern) {
         var s = (VarDeclPattern)stmt;
         var lhss = SubstituteCasePattern(s.LHS, false, CloneLocalVariable);
-        var rr = new VarDeclPattern(s.RangeToken, lhss, (Expression)Substitute(s.RHS), s.HasGhostModifier);
+        var rr = new VarDeclPattern(s.Origin, lhss, (Expression)Substitute(s.RHS), s.HasGhostModifier);
         r = rr;
       } else if (stmt is HideRevealStmt revealStmt) {
         // don't need to substitute s.Expr since it won't be used, only the s.ResolvedStatements are used.
         var rr = revealStmt.Wildcard
-          ? new HideRevealStmt(revealStmt.RangeToken, revealStmt.Mode)
-          : new HideRevealStmt(revealStmt.RangeToken, revealStmt.Exprs, revealStmt.Mode);
+          ? new HideRevealStmt(revealStmt.Origin, revealStmt.Mode)
+          : new HideRevealStmt(revealStmt.Origin, revealStmt.Exprs, revealStmt.Mode);
         rr.LabeledAsserts.AddRange(revealStmt.LabeledAsserts);
         rr.ResolvedStatements.AddRange(revealStmt.ResolvedStatements.ConvertAll(SubstStmt));
         rr.OffsetMembers = revealStmt.OffsetMembers.ToList();
         r = rr;
       } else if (stmt is BlockByProofStmt blockByProofStmt) {
-        var rr = new BlockByProofStmt(blockByProofStmt.RangeToken,
+        var rr = new BlockByProofStmt(blockByProofStmt.Origin,
           (BlockStmt)SubstStmt(blockByProofStmt.Proof),
           SubstStmt(blockByProofStmt.Body));
         r = rr;
@@ -916,7 +916,7 @@ protected void AddStmtLabels(Statement s, LList<Label> node) {
     }
 
     protected virtual DividedBlockStmt SubstDividedBlockStmt(DividedBlockStmt stmt) {
-      return stmt == null ? null : new DividedBlockStmt(stmt.RangeToken, stmt.BodyInit.ConvertAll(SubstStmt), stmt.SeparatorTok, stmt.BodyProper.ConvertAll(SubstStmt));
+      return stmt == null ? null : new DividedBlockStmt(stmt.Origin, stmt.BodyInit.ConvertAll(SubstStmt), stmt.SeparatorTok, stmt.BodyProper.ConvertAll(SubstStmt));
     }
 
     protected virtual BlockStmt SubstBlockStmt(BlockStmt stmt) {
@@ -924,7 +924,7 @@ protected virtual BlockStmt SubstBlockStmt(BlockStmt stmt) {
         return null;
       }
       var prevSubstMap = new Dictionary<IVariable, Expression>(substMap);
-      var b = new BlockStmt(stmt.RangeToken, stmt.Body.ConvertAll(SubstStmt));
+      var b = new BlockStmt(stmt.Origin, stmt.Body.ConvertAll(SubstStmt));
       if (substMap.Count != prevSubstMap.Count) {
         // reset substMap to what it was (note that substMap is a readonly field, so we can't just change it back to prevSubstMap)
         substMap.Clear();
@@ -943,7 +943,7 @@ protected GuardedAlternative SubstGuardedAlternative(GuardedAlternative alt) {
 
     protected AttributedExpression SubstMayBeFreeExpr(AttributedExpression expr) {
       Contract.Requires(expr != null);
-      var mfe = new AttributedExpression(Substitute(expr.E));
+      var mfe = new AttributedExpression(expr.Origin, Substitute(expr.E));
       mfe.Attributes = SubstAttributes(expr.Attributes);
       return mfe;
     }
@@ -983,7 +983,7 @@ protected AssignmentRhs SubstRHS(AssignmentRhs rhs) {
     protected MatchCaseStmt SubstMatchCaseStmt(MatchCaseStmt c) {
       Contract.Requires(c != null);
       var newBoundVars = CreateBoundVarSubstitutions(c.Arguments, false);
-      var r = new MatchCaseStmt(c.RangeToken, c.Ctor, c.FromBoundVar, newBoundVars, c.Body.ConvertAll(SubstStmt), c.Attributes);
+      var r = new MatchCaseStmt(c.Origin, c.Ctor, c.FromBoundVar, newBoundVars, c.Body.ConvertAll(SubstStmt), c.Attributes);
       r.Ctor = c.Ctor;
       // undo any changes to substMap (could be optimized to do this only if newBoundVars != e.Vars)
       foreach (var bv in c.Arguments) {
@@ -1067,19 +1067,19 @@ protected Expression SubstituteComprehensionExpr(ComprehensionExpr expr, bool fo
       if (newBoundVars != e.BoundVars || newRange != e.Range || newTerm != e.Term || newAttrs != e.Attributes ||
           newBounds != e.Bounds || !forceSubstituteOfBoundVars) {
         if (e is SetComprehension) {
-          newExpr = new SetComprehension(e.BodyStartTok, e.RangeToken, ((SetComprehension)e).Finite, newBoundVars,
+          newExpr = new SetComprehension(e.BodyStartTok, e.Origin, ((SetComprehension)e).Finite, newBoundVars,
             newRange, newTerm, newAttrs);
         } else if (e is MapComprehension) {
           var mc = (MapComprehension)e;
           var newTermLeft = mc.IsGeneralMapComprehension ? Substitute(mc.TermLeft) : null;
-          newExpr = new MapComprehension(e.BodyStartTok, e.RangeToken, mc.Finite, newBoundVars, newRange, newTermLeft, newTerm, newAttrs);
+          newExpr = new MapComprehension(e.BodyStartTok, e.Origin, mc.Finite, newBoundVars, newRange, newTermLeft, newTerm, newAttrs);
         } else if (expr is ForallExpr forallExpr) {
-          newExpr = new ForallExpr(expr.tok, e.RangeToken, newBoundVars, newRange, newTerm, newAttrs);
+          newExpr = new ForallExpr(expr.tok, e.Origin, newBoundVars, newRange, newTerm, newAttrs);
         } else if (expr is ExistsExpr existsExpr) {
-          newExpr = new ExistsExpr(expr.tok, e.RangeToken, newBoundVars, newRange, newTerm, newAttrs);
+          newExpr = new ExistsExpr(expr.tok, e.Origin, newBoundVars, newRange, newTerm, newAttrs);
         } else if (expr is LambdaExpr) {
           var l = (LambdaExpr)expr;
-          newExpr = new LambdaExpr(e.BodyStartTok, e.RangeToken, newBoundVars, newRange,
+          newExpr = new LambdaExpr(e.BodyStartTok, e.Origin, newBoundVars, newRange,
             SubstSpecFrameExpr(l.Reads), newTerm);
         } else {
           Contract.Assert(false); // unexpected ComprehensionExpr
diff --git a/Source/DafnyCore/AST/SystemModuleManager.cs b/Source/DafnyCore/AST/SystemModuleManager.cs
index a60cce44249..cfce4494ccc 100644
--- a/Source/DafnyCore/AST/SystemModuleManager.cs
+++ b/Source/DafnyCore/AST/SystemModuleManager.cs
@@ -302,7 +302,7 @@ Function CreateMember(string name, Type resultType, Function readsFunction = nul
       var args = Util.Map(Enumerable.Range(0, arity), i => new Formal(tok, "x" + i, tys[i], true, false, null));
       var argExprs = args.ConvertAll(a =>
         (Expression)new IdentifierExpr(tok, a.Name) { Var = a, Type = a.Type });
-      var readsIS = new FunctionCallExpr(tok, "reads", new ImplicitThisExpr(tok), tok, tok, argExprs) {
+      var readsIS = new FunctionCallExpr(tok, "reads", new ImplicitThisExpr(tok), Token.NoToken, Token.NoToken, argExprs) {
         Type = ObjectSetType(),
       };
       var readsFrame = new List<FrameExpression> { new FrameExpression(tok, readsIS, null) };
@@ -333,7 +333,7 @@ Function CreateMember(string name, Type resultType, Function readsFunction = nul
     var id = new BoundVar(tok, "f", new ArrowType(tok, arrowDecl, tys));
     var partialArrow = new SubsetTypeDecl(RangeToken.NoToken, new Name(ArrowType.PartialArrowTypeName(arity)),
       new TypeParameter.TypeParameterCharacteristics(false), tps, SystemModule,
-      id, ArrowSubtypeConstraint(tok, tok.ToRange(), id, reads, tps, false), SubsetTypeDecl.WKind.Special, null, DontCompile());
+      id, ArrowSubtypeConstraint(tok, tok, id, reads, tps, false), SubsetTypeDecl.WKind.Special, null, DontCompile());
     ((RedirectingTypeDecl)partialArrow).ConstraintIsCompilable = false;
     PartialArrowTypeDecls.Add(arity, partialArrow);
     SystemModule.SourceDecls.Add(partialArrow);
@@ -348,7 +348,7 @@ Function CreateMember(string name, Type resultType, Function readsFunction = nul
     id = new BoundVar(tok, "f", new UserDefinedType(tok, partialArrow.Name, partialArrow, tys));
     var totalArrow = new SubsetTypeDecl(RangeToken.NoToken, new Name(ArrowType.TotalArrowTypeName(arity)),
       new TypeParameter.TypeParameterCharacteristics(false), tps, SystemModule,
-      id, ArrowSubtypeConstraint(tok, tok.ToRange(), id, req, tps, true), SubsetTypeDecl.WKind.Special, null, DontCompile());
+      id, ArrowSubtypeConstraint(tok, tok, id, req, tps, true), SubsetTypeDecl.WKind.Special, null, DontCompile());
     ((RedirectingTypeDecl)totalArrow).ConstraintIsCompilable = false;
     TotalArrowTypeDecls.Add(arity, totalArrow);
     SystemModule.SourceDecls.Add(totalArrow);
@@ -360,7 +360,7 @@ Function CreateMember(string name, Type resultType, Function readsFunction = nul
   /// the built-in total-arrow type (if "total", in which case "member" is expected to denote the "requires" member).
   /// The given "id" is expected to be already resolved.
   /// </summary>
-  private Expression ArrowSubtypeConstraint(IOrigin tok, RangeToken rangeOrigin, BoundVar id, Function member, List<TypeParameter> tps, bool total) {
+  private Expression ArrowSubtypeConstraint(IOrigin tok, IOrigin rangeToken, BoundVar id, Function member, List<TypeParameter> tps, bool total) {
     Contract.Requires(tok != null);
     Contract.Requires(id != null);
     Contract.Requires(member != null);
@@ -384,7 +384,7 @@ private Expression ArrowSubtypeConstraint(IOrigin tok, RangeToken rangeOrigin, B
       TypeApplicationJustMember = new List<Type>(),
       Type = GetTypeOfFunction(member, tps.ConvertAll(tp => (Type)new UserDefinedType(tp)), new List<Type>())
     };
-    Expression body = new ApplyExpr(tok, fn, args, tok);
+    Expression body = new ApplyExpr(tok, fn, args, Token.NoToken);
     body.Type = member.ResultType;  // resolve here
     if (!total) {
       Expression emptySet = new SetDisplayExpr(tok, true, new List<Expression>());
@@ -392,7 +392,7 @@ private Expression ArrowSubtypeConstraint(IOrigin tok, RangeToken rangeOrigin, B
       body = Expression.CreateEq(body, emptySet, member.ResultType);
     }
     if (tps.Count > 1) {
-      body = new ForallExpr(tok, rangeOrigin, bvs, null, body, null) { Type = Type.Bool, Bounds = bounds };
+      body = new ForallExpr(tok, rangeToken, bvs, null, body, null) { Type = Type.Bool, Bounds = bounds };
     }
     return body;
   }
diff --git a/Source/DafnyCore/AST/Tokens.cs b/Source/DafnyCore/AST/Tokens.cs
index 997528bb905..08a696af75f 100644
--- a/Source/DafnyCore/AST/Tokens.cs
+++ b/Source/DafnyCore/AST/Tokens.cs
@@ -2,6 +2,9 @@
 using System;
 using System.Diagnostics.Contracts;
 using System.IO;
+using System.Text;
+using OmniSharp.Extensions.LanguageServer.Protocol.Models;
+using Range = OmniSharp.Extensions.LanguageServer.Protocol.Models.Range;
 
 namespace Microsoft.Dafny;
 
@@ -53,7 +56,25 @@ public Token(int linenum, int colnum) {
 
   public bool IsValid => this.ActualFilename != null;
 
-  public IOrigin WithVal(string newVal) {
+  public RangeToken To(Token end) => new(this, end);
+
+  public bool IsMissingRange => true;
+
+  public bool IsInherited(ModuleDefinition d) {
+    return false;
+  }
+
+  public Token Center => this;
+  public Token StartToken => this;
+  public Token EndToken => this;
+  public bool ContainsRange => false;
+  public string filename => Path.GetFileName(Filepath);
+
+  IOrigin IOrigin.WithVal(string val) {
+    return WithVal(val);
+  }
+
+  public Token WithVal(string newVal) {
     return new Token {
       pos = pos,
       col = col,
@@ -92,12 +113,85 @@ public int CompareTo(IOrigin other) {
 }
 
 public static class TokenExtensions {
+  public static IOrigin WithCenter(this IOrigin origin, Token center) {
+    return new RangeToken(origin.StartToken, origin.EndToken, center);
+  }
+
+  public static IOrigin WithEnd(this IOrigin origin, Token end) {
+    return new RangeToken(origin.StartToken, end, origin.Center);
+  }
 
+  public static RangeToken SingleTokenRange(this Token token) {
+    return new RangeToken(token, token);
+  }
+
+  /// <summary>
+  /// Gets the LSP range of the specified token.
+  /// </summary>
+  /// <param name="startToken">The token to get the range of.</param>
+  /// <param name="endToken">An optional other token to get the end of the range of.</param>
+  /// <returns>The LSP range of the token.</returns>
+  public static Range ToLspRange(this IOrigin range) {
+    return range.ToDafnyRange().ToLspRange();
+  }
+
+  public static DafnyRange ToDafnyRange(this IOrigin origin, bool includeTrailingWhitespace = false) {
+    var startLine = origin.StartToken.line - 1;
+    var startColumn = origin.StartToken.col - 1;
+    var endLine = origin.EndToken.line - 1;
+    int whitespaceOffset = 0;
+    if (includeTrailingWhitespace) {
+      string trivia = origin.EndToken.TrailingTrivia;
+      // Don't want to remove newlines or comments -- just spaces and tabs
+      while (whitespaceOffset < trivia.Length && (trivia[whitespaceOffset] == ' ' || trivia[whitespaceOffset] == '\t')) {
+        whitespaceOffset++;
+      }
+    }
+
+    var endColumn = origin.EndToken.col + (origin.InclusiveEnd ? origin.EndToken.val.Length : 0) + whitespaceOffset - 1;
+    return new DafnyRange(
+      new DafnyPosition(startLine, startColumn),
+      new DafnyPosition(endLine, endColumn));
+  }
+
+
+  public static bool Contains(this IOrigin origin, IOrigin otherToken) {
+    return origin.StartToken.Uri == otherToken.Uri &&
+           origin.StartToken.pos <= otherToken.pos &&
+           (origin.EndToken == null || otherToken.pos <= origin.EndToken.pos);
+  }
+
+  public static bool Intersects(this IOrigin origin, IOrigin other) {
+    return !(other.EndToken.pos + other.EndToken.val.Length <= origin.StartToken.pos
+             || origin.EndToken.pos + origin.EndToken.val.Length <= other.StartToken.pos);
+  }
+
+  public static string PrintOriginal(this IOrigin origin) {
+    var token = origin.StartToken;
+    var originalString = new StringBuilder();
+    originalString.Append(token.val);
+    while (token.Next != null && token.pos < origin.EndToken.pos) {
+      originalString.Append(token.TrailingTrivia);
+      token = token.Next;
+      originalString.Append(token.LeadingTrivia);
+      originalString.Append(token.val);
+    }
+
+    return originalString.ToString();
+  }
+
+  public static IOrigin MakeAutoGenerated(this IOrigin origin) {
+    return new AutoGeneratedOrigin(origin);
+  }
+
+  public static IOrigin MakeRefined(this IOrigin origin, ModuleDefinition module) {
+    return new RefinementOrigin(origin, module);
+  }
 
   public static bool IsSet(this IOrigin token) => token.Uri != null;
 
   public static string TokenToString(this IOrigin tok, DafnyOptions options) {
-    if (tok == Token.Cli) {
+    if (ReferenceEquals(tok, Token.Cli)) {
       return "CLI";
     }
 
@@ -117,36 +211,33 @@ public static string TokenToString(this IOrigin tok, DafnyOptions options) {
     return $"{filename}({tok.line},{tok.col - 1})";
   }
 
-  public static RangeToken ToRange(this IOrigin token) {
-    if (token is BoogieRangeOrigin boogieRangeToken) {
-      return new RangeToken(boogieRangeToken.StartToken, boogieRangeToken.EndToken);
+  public static IOrigin Unwrap(this IOrigin token) {
+    if (token is OriginWrapper wrapper) {
+      return Unwrap(wrapper.WrappedOrigin);
     }
 
-    if (token is NestedOrigin nestedToken) {
-      return ToRange(nestedToken.Outer);
-    }
-    return token as RangeToken ?? new RangeToken(token, token);
+    return token;
   }
 }
 
 public class BoogieRangeOrigin : OriginWrapper {
   // The wrapped token is the startTok
-  public IOrigin StartToken { get; }
-  public IOrigin EndToken { get; }
+  public override Token StartToken { get; }
+  public override Token EndToken { get; }
 
   /// <summary>
   /// If only a single position is used to refer to this piece of code, this position is the best
   /// </summary>
-  public IOrigin Center { get; }
+  public IOrigin Centerish { get; }
 
   // Used for range reporting
   public override string val => new(' ', Math.Max(EndToken.pos + EndToken.val.Length - pos, 1));
 
-  public BoogieRangeOrigin(IOrigin startTok, IOrigin endTok, IOrigin center) : base(
+  public BoogieRangeOrigin(Token startTok, Token endTok, IOrigin center) : base(
     center ?? startTok) {
     StartToken = startTok;
     EndToken = endTok;
-    Center = center;
+    Centerish = center;
   }
 
   public override IOrigin WithVal(string newVal) {
@@ -166,7 +257,10 @@ public NestedOrigin(IOrigin outer, IOrigin inner, string message = null)
     Inner = inner;
     this.Message = message;
   }
-  public IOrigin Outer { get { return WrappedToken; } }
+
+  public override bool IsInherited(ModuleDefinition d) => Outer.IsInherited(d) || Inner.IsInherited(d);
+
+  public IOrigin Outer => WrappedOrigin;
   public readonly IOrigin Inner;
   public readonly string Message;
 
@@ -180,18 +274,18 @@ public override IOrigin WithVal(string newVal) {
 /// for quantified variables. See QuantifierVar.ExtractSingleRange()
 /// </summary>
 public class QuantifiedVariableDomainOrigin : OriginWrapper {
-  public QuantifiedVariableDomainOrigin(IOrigin wrappedToken)
-    : base(wrappedToken) {
-    Contract.Requires(wrappedToken != null);
+  public QuantifiedVariableDomainOrigin(IOrigin wrappedOrigin)
+    : base(wrappedOrigin) {
+    Contract.Requires(wrappedOrigin != null);
   }
 
   public override string val {
-    get { return WrappedToken.val; }
-    set { WrappedToken.val = value; }
+    get { return WrappedOrigin.val; }
+    set { WrappedOrigin.val = value; }
   }
 
   public override IOrigin WithVal(string newVal) {
-    return new QuantifiedVariableDomainOrigin((WrappedToken.WithVal(newVal)));
+    return new QuantifiedVariableDomainOrigin((WrappedOrigin.WithVal(newVal)));
   }
 }
 
@@ -200,17 +294,17 @@ public override IOrigin WithVal(string newVal) {
 /// for quantified variables. See QuantifierVar.ExtractSingleRange()
 /// </summary>
 public class QuantifiedVariableRangeOrigin : OriginWrapper {
-  public QuantifiedVariableRangeOrigin(IOrigin wrappedToken)
-    : base(wrappedToken) {
-    Contract.Requires(wrappedToken != null);
+  public QuantifiedVariableRangeOrigin(IOrigin wrappedOrigin)
+    : base(wrappedOrigin) {
+    Contract.Requires(wrappedOrigin != null);
   }
 
   public override string val {
-    get { return WrappedToken.val; }
-    set { WrappedToken.val = value; }
+    get { return WrappedOrigin.val; }
+    set { WrappedOrigin.val = value; }
   }
 
   public override IOrigin WithVal(string newVal) {
-    return new QuantifiedVariableRangeOrigin(WrappedToken.WithVal(newVal));
+    return new QuantifiedVariableRangeOrigin(WrappedOrigin.WithVal(newVal));
   }
 }
diff --git a/Source/DafnyCore/AST/TypeDeclarations/AbstractTypeDecl.cs b/Source/DafnyCore/AST/TypeDeclarations/AbstractTypeDecl.cs
index 8e1cc55648e..471974265b6 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/AbstractTypeDecl.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/AbstractTypeDecl.cs
@@ -11,7 +11,7 @@ public bool SupportsEquality {
     get { return Characteristics.EqualitySupport != TypeParameter.EqualitySupportValue.Unspecified; }
   }
 
-  public AbstractTypeDecl(RangeToken rangeOrigin, Name name, ModuleDefinition module, TypeParameter.TypeParameterCharacteristics characteristics,
+  public AbstractTypeDecl(IOrigin rangeOrigin, Name name, ModuleDefinition module, TypeParameter.TypeParameterCharacteristics characteristics,
     List<TypeParameter> typeArgs, List<Type> parentTraits, List<MemberDecl> members, Attributes attributes, bool isRefining)
     : base(rangeOrigin, name, module, typeArgs, members, attributes, isRefining, parentTraits) {
     Contract.Requires(rangeOrigin != null);
diff --git a/Source/DafnyCore/AST/TypeDeclarations/ArrayClassDecl.cs b/Source/DafnyCore/AST/TypeDeclarations/ArrayClassDecl.cs
index 8b691e9c1c1..f960a95f634 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/ArrayClassDecl.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/ArrayClassDecl.cs
@@ -8,8 +8,8 @@ public class ArrayClassDecl : ClassDecl {
 
   public readonly int Dims;
   public ArrayClassDecl(int dims, ModuleDefinition module, Attributes attrs)
-    : base(RangeToken.NoToken, new Name(SystemModuleManager.ArrayClassName(dims)), module,
-      new List<TypeParameter>(new TypeParameter[] { new TypeParameter(RangeToken.NoToken, new Name("arg"), TypeParameter.TPVarianceSyntax.NonVariant_Strict) }),
+    : base(Dafny.RangeToken.NoToken, new Name(SystemModuleManager.ArrayClassName(dims)), module,
+      new List<TypeParameter>(new TypeParameter[] { new TypeParameter(Dafny.RangeToken.NoToken, new Name("arg"), TypeParameter.TPVarianceSyntax.NonVariant_Strict) }),
       new List<MemberDecl>(), attrs, false, null) {
     Contract.Requires(1 <= dims);
     Contract.Requires(module != null);
diff --git a/Source/DafnyCore/AST/TypeDeclarations/ClassDecl.cs b/Source/DafnyCore/AST/TypeDeclarations/ClassDecl.cs
index 2adb01a91b5..af54ff39e4b 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/ClassDecl.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/ClassDecl.cs
@@ -15,7 +15,7 @@ void ObjectInvariant() {
     Contract.Invariant(ParentTraits != null);
   }
 
-  public ClassDecl(RangeToken rangeOrigin, Name name, ModuleDefinition module,
+  public ClassDecl(IOrigin rangeOrigin, Name name, ModuleDefinition module,
     List<TypeParameter> typeArgs, [Captured] List<MemberDecl> members, Attributes attributes, bool isRefining, List<Type>/*?*/ traits)
     : base(rangeOrigin, name, module, typeArgs, members, attributes, isRefining, traits) {
     Contract.Requires(rangeOrigin != null);
diff --git a/Source/DafnyCore/AST/TypeDeclarations/ClassLikeDecl.cs b/Source/DafnyCore/AST/TypeDeclarations/ClassLikeDecl.cs
index ec287a98579..828f0796fa2 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/ClassLikeDecl.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/ClassLikeDecl.cs
@@ -24,7 +24,7 @@ public bool IsObjectTrait {
   public TopLevelDecl AsTopLevelDecl => this;
   public TypeDeclSynonymInfo SynonymInfo { get; set; }
 
-  public ClassLikeDecl(RangeToken rangeOrigin, Name name, ModuleDefinition module,
+  public ClassLikeDecl(IOrigin rangeOrigin, Name name, ModuleDefinition module,
     List<TypeParameter> typeArgs, [Captured] List<MemberDecl> members, Attributes attributes, bool isRefining, List<Type>/*?*/ traits)
     : base(rangeOrigin, name, module, typeArgs, members, attributes, isRefining, traits) {
     Contract.Requires(rangeOrigin != null);
diff --git a/Source/DafnyCore/AST/TypeDeclarations/CoDatatypeDecl.cs b/Source/DafnyCore/AST/TypeDeclarations/CoDatatypeDecl.cs
index b86272eab7b..d1de640ee9d 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/CoDatatypeDecl.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/CoDatatypeDecl.cs
@@ -8,7 +8,7 @@ public class CoDatatypeDecl : DatatypeDecl {
   public override string WhatKind { get { return "codatatype"; } }
   [FilledInDuringResolution] public CoDatatypeDecl SscRepr;
 
-  public CoDatatypeDecl(RangeToken rangeOrigin, Name name, ModuleDefinition module, List<TypeParameter> typeArgs,
+  public CoDatatypeDecl(IOrigin rangeOrigin, Name name, ModuleDefinition module, List<TypeParameter> typeArgs,
     [Captured] List<DatatypeCtor> ctors, List<Type> parentTraits, List<MemberDecl> members, Attributes attributes, bool isRefining)
     : base(rangeOrigin, name, module, typeArgs, ctors, parentTraits, members, attributes, isRefining) {
     Contract.Requires(rangeOrigin != null);
diff --git a/Source/DafnyCore/AST/TypeDeclarations/DatatypeCtor.cs b/Source/DafnyCore/AST/TypeDeclarations/DatatypeCtor.cs
index 03439bd52b4..15368e12935 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/DatatypeCtor.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/DatatypeCtor.cs
@@ -24,7 +24,7 @@ void ObjectInvariant() {
   [FilledInDuringResolution] public SpecialField QueryField;
   [FilledInDuringResolution] public List<DatatypeDestructor> Destructors = new List<DatatypeDestructor>();  // includes both implicit (not mentionable in source) and explicit destructors
 
-  public DatatypeCtor(RangeToken rangeOrigin, Name name, bool isGhost, [Captured] List<Formal> formals, Attributes attributes)
+  public DatatypeCtor(IOrigin rangeOrigin, Name name, bool isGhost, [Captured] List<Formal> formals, Attributes attributes)
     : base(rangeOrigin, name, attributes, false) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(name != null);
diff --git a/Source/DafnyCore/AST/TypeDeclarations/DatatypeDecl.cs b/Source/DafnyCore/AST/TypeDeclarations/DatatypeDecl.cs
index 3cfbb646c25..bd6a62e9ae6 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/DatatypeDecl.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/DatatypeDecl.cs
@@ -21,7 +21,7 @@ void ObjectInvariant() {
 
   public override IEnumerable<INode> PreResolveChildren => Ctors.Concat(base.PreResolveChildren);
 
-  public DatatypeDecl(RangeToken rangeOrigin, Name name, ModuleDefinition module, List<TypeParameter> typeArgs,
+  public DatatypeDecl(IOrigin rangeOrigin, Name name, ModuleDefinition module, List<TypeParameter> typeArgs,
     [Captured] List<DatatypeCtor> ctors, List<Type> parentTraits, List<MemberDecl> members, Attributes attributes, bool isRefining)
     : base(rangeOrigin, name, module, typeArgs, members, attributes, isRefining, parentTraits) {
     Contract.Requires(rangeOrigin != null);
diff --git a/Source/DafnyCore/AST/TypeDeclarations/Declaration.cs b/Source/DafnyCore/AST/TypeDeclarations/Declaration.cs
index 42e64f7bf1b..c931962af34 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/Declaration.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/Declaration.cs
@@ -15,8 +15,8 @@ void ObjectInvariant() {
   public IOrigin BodyStartTok = Token.NoToken;
   public Name NameNode;
 
-  public override IOrigin Tok => NameNode.StartToken;
-  public virtual IOrigin NavigationToken => NameNode.StartToken;
+  public override IOrigin Tok => NameNode.Origin;
+  public virtual IOrigin NavigationToken => NameNode.Origin;
 
   public string Name => NameNode.Value;
   public bool IsRefining;
@@ -28,11 +28,11 @@ void ObjectInvariant() {
 
   protected Declaration(Cloner cloner, Declaration original) : base(cloner, original) {
     NameNode = original.NameNode.Clone(cloner);
-    BodyStartTok = cloner.Tok(original.BodyStartTok);
+    BodyStartTok = cloner.Origin(original.BodyStartTok);
     Attributes = cloner.CloneAttributes(original.Attributes);
   }
 
-  protected Declaration(RangeToken rangeOrigin, Name name, Attributes attributes, bool isRefining) : base(rangeOrigin) {
+  protected Declaration(IOrigin rangeOrigin, Name name, Attributes attributes, bool isRefining) : base(rangeOrigin) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(name != null);
     this.NameNode = name;
diff --git a/Source/DafnyCore/AST/TypeDeclarations/IndDatatypeDecl.cs b/Source/DafnyCore/AST/TypeDeclarations/IndDatatypeDecl.cs
index 3a37788c0eb..34868ddaedd 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/IndDatatypeDecl.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/IndDatatypeDecl.cs
@@ -32,7 +32,7 @@ public bool[] TypeParametersUsedInConstructionByGroundingCtor {
   public enum ES { NotYetComputed, Never, ConsultTypeArguments }
   public ES EqualitySupport = ES.NotYetComputed;
 
-  public IndDatatypeDecl(RangeToken rangeOrigin, Name name, ModuleDefinition module, List<TypeParameter> typeArgs,
+  public IndDatatypeDecl(IOrigin rangeOrigin, Name name, ModuleDefinition module, List<TypeParameter> typeArgs,
     [Captured] List<DatatypeCtor> ctors, List<Type> parentTraits, List<MemberDecl> members, Attributes attributes, bool isRefining)
     : base(rangeOrigin, name, module, typeArgs, ctors, parentTraits, members, attributes, isRefining) {
     Contract.Requires(rangeOrigin != null);
diff --git a/Source/DafnyCore/AST/TypeDeclarations/IteratorDecl.cs b/Source/DafnyCore/AST/TypeDeclarations/IteratorDecl.cs
index b723d9d89b2..72fe1fa9da9 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/IteratorDecl.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/IteratorDecl.cs
@@ -29,7 +29,7 @@ public class IteratorDecl : ClassDecl, IMethodCodeContext, ICanVerify, ICodeCont
   [FilledInDuringResolution] public Method Member_MoveNext;  // created during registration phase of resolution;
   public readonly LocalVariable YieldCountVariable;
 
-  public IteratorDecl(RangeToken rangeOrigin, Name name, ModuleDefinition module, List<TypeParameter> typeArgs,
+  public IteratorDecl(IOrigin rangeOrigin, Name name, ModuleDefinition module, List<TypeParameter> typeArgs,
     List<Formal> ins, List<Formal> outs,
     Specification<FrameExpression> reads, Specification<FrameExpression> mod, Specification<Expression> decreases,
     List<AttributedExpression> requires,
@@ -200,27 +200,27 @@ public void CreateIteratorMethodSpecs(ModuleResolver resolver) {
     var ens = Member_Init.Ens;
     foreach (var p in Ins) {
       // ensures this.x == x;
-      ens.Add(new AttributedExpression(new BinaryExpr(p.tok, BinaryExpr.Opcode.Eq,
+      ens.Add(new AttributedExpression(tok, new BinaryExpr(p.tok, BinaryExpr.Opcode.Eq,
         new ExprDotName(p.tok, new ThisExpr(p.tok), p.Name, null), new IdentifierExpr(p.tok, p.Name))));
     }
     foreach (var p in OutsHistoryFields) {
       // ensures this.ys == [];
-      ens.Add(new AttributedExpression(new BinaryExpr(p.tok, BinaryExpr.Opcode.Eq,
+      ens.Add(new AttributedExpression(tok, new BinaryExpr(p.tok, BinaryExpr.Opcode.Eq,
         new ExprDotName(p.tok, new ThisExpr(p.tok), p.Name, null), new SeqDisplayExpr(p.tok, new List<Expression>()))));
     }
     // ensures this.Valid();
-    var valid_call = AutoContractsRewriter.CreateUnresolvedValidCall(tok);
-    ens.Add(new AttributedExpression(valid_call));
+    var validCall = AutoContractsRewriter.CreateUnresolvedValidCall(tok);
+    ens.Add(new AttributedExpression(tok, validCall));
     AddConstructorFramePostconditions(tok, ens, resolver);
     // ensures this._new == {};
-    ens.Add(new AttributedExpression(new BinaryExpr(tok, BinaryExpr.Opcode.Eq,
+    ens.Add(new AttributedExpression(tok, new BinaryExpr(tok, BinaryExpr.Opcode.Eq,
       new ExprDotName(tok, new ThisExpr(tok), "_new", null),
       new SetDisplayExpr(tok, true, new List<Expression>()))));
     // ensures this._decreases0 == old(DecreasesClause[0]) && ...;
     Contract.Assert(Decreases.Expressions.Count == DecreasesFields.Count);
     for (int i = 0; i < Decreases.Expressions.Count; i++) {
       var p = Decreases.Expressions[i];
-      ens.Add(new AttributedExpression(new BinaryExpr(tok, BinaryExpr.Opcode.Eq,
+      ens.Add(new AttributedExpression(tok, new BinaryExpr(tok, BinaryExpr.Opcode.Eq,
         new ExprDotName(tok, new ThisExpr(tok), DecreasesFields[i].Name, null),
         new OldExpr(tok, p))));
     }
@@ -234,8 +234,8 @@ public void CreateIteratorMethodSpecs(ModuleResolver resolver) {
     // ---------- here comes method MoveNext() ----------
     // requires this.Valid();
     var req = Member_MoveNext.Req;
-    valid_call = AutoContractsRewriter.CreateUnresolvedValidCall(tok);
-    req.Add(new AttributedExpression(valid_call));
+    validCall = AutoContractsRewriter.CreateUnresolvedValidCall(tok);
+    req.Add(new AttributedExpression(tok, validCall));
     // requires YieldRequires;
     req.AddRange(YieldRequires);
     // modifies this, this._modifies, this._new;
@@ -245,19 +245,19 @@ public void CreateIteratorMethodSpecs(ModuleResolver resolver) {
     mod.Add(new FrameExpression(tok, new ExprDotName(tok, new ThisExpr(tok), "_new", null), null));
     // ensures fresh(_new - old(_new));
     ens = Member_MoveNext.Ens;
-    ens.Add(new AttributedExpression(new FreshExpr(tok,
+    ens.Add(new AttributedExpression(tok, new FreshExpr(tok,
       new BinaryExpr(tok, BinaryExpr.Opcode.Sub,
         new ExprDotName(tok, new ThisExpr(tok), "_new", null),
         new OldExpr(tok, new ExprDotName(tok, new ThisExpr(tok), "_new", null))))));
     // ensures null !in _new
-    ens.Add(new AttributedExpression(new BinaryExpr(tok, BinaryExpr.Opcode.NotIn,
+    ens.Add(new AttributedExpression(tok, new BinaryExpr(tok, BinaryExpr.Opcode.NotIn,
       new LiteralExpr(tok),
       new ExprDotName(tok, new ThisExpr(tok), "_new", null))));
     // ensures more ==> this.Valid();
-    valid_call = AutoContractsRewriter.CreateUnresolvedValidCall(tok);
-    ens.Add(new AttributedExpression(new BinaryExpr(tok, BinaryExpr.Opcode.Imp,
+    validCall = AutoContractsRewriter.CreateUnresolvedValidCall(tok);
+    ens.Add(new AttributedExpression(tok, new BinaryExpr(tok, BinaryExpr.Opcode.Imp,
       new IdentifierExpr(tok, "more"),
-      valid_call)));
+      validCall)));
     // ensures this.ys == if more then old(this.ys) + [this.y] else old(this.ys);
     Contract.Assert(OutsFields.Count == OutsHistoryFields.Count);
     for (int i = 0; i < OutsFields.Count; i++) {
@@ -269,17 +269,17 @@ public void CreateIteratorMethodSpecs(ModuleResolver resolver) {
           new SeqDisplayExpr(tok, new List<Expression>() { new ExprDotName(tok, new ThisExpr(tok), y.Name, null) })),
         new OldExpr(tok, new ExprDotName(tok, new ThisExpr(tok), ys.Name, null)));
       var eq = new BinaryExpr(tok, BinaryExpr.Opcode.Eq, new ExprDotName(tok, new ThisExpr(tok), ys.Name, null), ite);
-      ens.Add(new AttributedExpression(eq));
+      ens.Add(new AttributedExpression(tok, eq));
     }
     // ensures more ==> YieldEnsures;
     foreach (var ye in YieldEnsures) {
-      ens.Add(new AttributedExpression(
+      ens.Add(new AttributedExpression(tok,
         new BinaryExpr(tok, BinaryExpr.Opcode.Imp, new IdentifierExpr(tok, "more"), ye.E)
       ));
     }
     // ensures !more ==> Ensures;
     foreach (var e in Ensures) {
-      ens.Add(new AttributedExpression(new BinaryExpr(tok, BinaryExpr.Opcode.Imp,
+      ens.Add(new AttributedExpression(tok, new BinaryExpr(tok, BinaryExpr.Opcode.Imp,
         new UnaryOpExpr(tok, UnaryOpExpr.Opcode.Not, new IdentifierExpr(tok, "more")),
         e.E)
       ));
@@ -313,7 +313,7 @@ private void AddConstructorFramePostconditions(AutoGeneratedOrigin tok, List<Att
         frameSet = new BinaryExpr(fr.tok, BinaryExpr.Opcode.Add, frameSet, fr.E);
       }
     }
-    iteratorCtorEnsures.Add(new AttributedExpression(new BinaryExpr(tok, BinaryExpr.Opcode.Eq,
+    iteratorCtorEnsures.Add(new AttributedExpression(tok, new BinaryExpr(tok, BinaryExpr.Opcode.Eq,
       new ExprDotName(tok, new ThisExpr(tok), "_reads", null),
       new OldExpr(tok, frameSet))));
 
@@ -330,13 +330,13 @@ private void AddConstructorFramePostconditions(AutoGeneratedOrigin tok, List<Att
         frameSet = new BinaryExpr(fr.tok, BinaryExpr.Opcode.Add, frameSet, fr.E);
       }
     }
-    iteratorCtorEnsures.Add(new AttributedExpression(new BinaryExpr(tok, BinaryExpr.Opcode.Eq,
+    iteratorCtorEnsures.Add(new AttributedExpression(tok, new BinaryExpr(tok, BinaryExpr.Opcode.Eq,
       new ExprDotName(tok, new ThisExpr(tok), "_modifies", null),
       new OldExpr(tok, frameSet))));
   }
 
   public void Resolve(ModuleResolver resolver) {
-    var rangeToken = RangeToken.MakeAutoGenerated();
+    var origin = Origin.MakeAutoGenerated();
 
     // register the names of the implicit members
     var members = new Dictionary<string, MemberDecl>();
@@ -348,7 +348,7 @@ public void Resolve(ModuleResolver resolver) {
         resolver.reporter.Error(MessageSource.Resolver, p,
           "Name of in-parameter is used by another member of the iterator: {0}", p.Name);
       } else {
-        var field = new SpecialField(p.RangeToken, p.Name, SpecialField.ID.UseIdParam, p.CompileName, p.IsGhost, false,
+        var field = new SpecialField(p.Origin, p.Name, SpecialField.ID.UseIdParam, p.CompileName, p.IsGhost, false,
           false, p.Type, null);
         field.EnclosingClass = this; // resolve here
         field.InheritVisibility(this);
@@ -364,7 +364,7 @@ public void Resolve(ModuleResolver resolver) {
           "Name of yield-parameter is used by another member of the iterator: {0}", p.Name);
       } else {
         nonDuplicateOuts.Add(p);
-        var field = new SpecialField(p.RangeToken, p.Name, SpecialField.ID.UseIdParam, p.CompileName, p.IsGhost, true,
+        var field = new SpecialField(p.Origin, p.Name, SpecialField.ID.UseIdParam, p.CompileName, p.IsGhost, true,
           true, p.Type, null);
         field.EnclosingClass = this; // resolve here
         field.InheritVisibility(this);
@@ -385,7 +385,7 @@ public void Resolve(ModuleResolver resolver) {
 
       // we add some field to OutsHistoryFields, even if there was an error; the name of the field, in case of error, is not so important
       var tp = new SeqType(p.Type.NormalizeExpand());
-      var field = new SpecialField(p.RangeToken, nm, SpecialField.ID.UseIdParam, nm, true, true, false, tp, null);
+      var field = new SpecialField(p.Origin, nm, SpecialField.ID.UseIdParam, nm, true, true, false, tp, null);
       field.EnclosingClass = this; // resolve here
       field.InheritVisibility(this);
       OutsHistoryFields
@@ -401,11 +401,11 @@ public void Resolve(ModuleResolver resolver) {
       Members.Add(f);
     });
     // add the additional special variables as fields
-    Member_Reads = new SpecialField(RangeToken, "_reads", SpecialField.ID.Reads, null, true, false, false,
+    Member_Reads = new SpecialField(Origin, "_reads", SpecialField.ID.Reads, null, true, false, false,
       resolver.SystemModuleManager.ObjectSetType(), null);
-    Member_Modifies = new SpecialField(RangeToken, "_modifies", SpecialField.ID.Modifies, null, true, false,
+    Member_Modifies = new SpecialField(Origin, "_modifies", SpecialField.ID.Modifies, null, true, false,
       false, resolver.SystemModuleManager.ObjectSetType(), null);
-    Member_New = new SpecialField(RangeToken, "_new", SpecialField.ID.New, null, true, true, true,
+    Member_New = new SpecialField(Origin, "_new", SpecialField.ID.New, null, true, true, true,
       resolver.SystemModuleManager.ObjectSetType(), null);
     foreach (var field in new List<Field>() { Member_Reads, Member_Modifies, Member_New }) {
       field.EnclosingClass = this; // resolve here
@@ -420,7 +420,7 @@ public void Resolve(ModuleResolver resolver) {
     var i = 0;
     foreach (var p in Decreases.Expressions) {
       var nm = "_decreases" + i;
-      var field = new SpecialField(p.RangeToken, nm, SpecialField.ID.UseIdParam, nm, true, false, false,
+      var field = new SpecialField(p.Origin, nm, SpecialField.ID.UseIdParam, nm, true, false, false,
         new InferredTypeProxy(), null);
       field.EnclosingClass = this; // resolve here
       field.InheritVisibility(this);
@@ -434,7 +434,7 @@ public void Resolve(ModuleResolver resolver) {
     // saying is that the Method/Predicate does not take any type parameters over and beyond what the enclosing type (namely, the
     // iterator type) does.
     // --- here comes the constructor
-    var init = new Constructor(rangeToken, new Name(NameNode.RangeToken, "_ctor"), false,
+    var init = new Constructor(origin, new Name(NameNode.Origin, "_ctor"), false,
       new List<TypeParameter>(), Ins,
       new List<AttributedExpression>(),
       new Specification<FrameExpression>(),
@@ -443,7 +443,7 @@ public void Resolve(ModuleResolver resolver) {
       new Specification<Expression>(new List<Expression>(), null),
       null, SystemModuleManager.AxiomAttribute(), null);
     // --- here comes predicate Valid()
-    var valid = new Predicate(rangeToken, new Name(NameNode.RangeToken, "Valid"), false, true, false,
+    var valid = new Predicate(origin, new Name(NameNode.Origin, "Valid"), false, true, false,
       new List<TypeParameter>(),
       new List<Formal>(),
       null,
@@ -453,7 +453,7 @@ public void Resolve(ModuleResolver resolver) {
       new Specification<Expression>(new List<Expression>(), null),
       null, Predicate.BodyOriginKind.OriginalOrInherited, null, null, SystemModuleManager.AxiomAttribute(), null);
     // --- here comes method MoveNext
-    var moveNext = new Method(rangeToken, new Name(NameNode.RangeToken, "MoveNext"), false, false,
+    var moveNext = new Method(origin, new Name(NameNode.Origin, "MoveNext"), false, false,
       new List<TypeParameter>(),
       new List<Formal>(), new List<Formal>() { new Formal(tok, "more", Type.Bool, false, false, null) },
       new List<AttributedExpression>(),
diff --git a/Source/DafnyCore/AST/TypeDeclarations/NewtypeDecl.cs b/Source/DafnyCore/AST/TypeDeclarations/NewtypeDecl.cs
index f58836510a8..608e237235e 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/NewtypeDecl.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/NewtypeDecl.cs
@@ -32,7 +32,7 @@ bool RedirectingTypeDecl.ConstraintIsCompilable {
 
   [FilledInDuringResolution] public bool TargetTypeCoversAllBitPatterns; // "target complete" -- indicates that any bit pattern that can fill the target type is a value of the newtype
 
-  public NewtypeDecl(RangeToken rangeOrigin, Name name, List<TypeParameter> typeParameters, ModuleDefinition module,
+  public NewtypeDecl(IOrigin rangeOrigin, Name name, List<TypeParameter> typeParameters, ModuleDefinition module,
     Type baseType,
     SubsetTypeDecl.WKind witnessKind, Expression witness, List<Type> parentTraits, List<MemberDecl> members, Attributes attributes, bool isRefining)
     : base(rangeOrigin, name, module, typeParameters, members, attributes, isRefining, parentTraits) {
@@ -47,7 +47,7 @@ public NewtypeDecl(RangeToken rangeOrigin, Name name, List<TypeParameter> typePa
     WitnessKind = witnessKind;
     this.NewSelfSynonym();
   }
-  public NewtypeDecl(RangeToken rangeOrigin, Name name, List<TypeParameter> typeParameters, ModuleDefinition module,
+  public NewtypeDecl(IOrigin rangeOrigin, Name name, List<TypeParameter> typeParameters, ModuleDefinition module,
     BoundVar bv, Expression constraint,
     SubsetTypeDecl.WKind witnessKind, Expression witness, List<Type> parentTraits, List<MemberDecl> members, Attributes attributes, bool isRefining)
     : base(rangeOrigin, name, module, typeParameters, members, attributes, isRefining, parentTraits) {
diff --git a/Source/DafnyCore/AST/TypeDeclarations/NonNullTypeDecl.cs b/Source/DafnyCore/AST/TypeDeclarations/NonNullTypeDecl.cs
index 9460420165a..10baedd7a8c 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/NonNullTypeDecl.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/NonNullTypeDecl.cs
@@ -25,7 +25,7 @@ private NonNullTypeDecl(ClassLikeDecl cl, List<TypeParameter> tps)
   }
 
   private NonNullTypeDecl(ClassLikeDecl cl, List<TypeParameter> tps, BoundVar id)
-    : base(cl.RangeToken, cl.NameNode, new TypeParameter.TypeParameterCharacteristics(), tps, cl.EnclosingModuleDefinition, id,
+    : base(cl.Origin, cl.NameNode, new TypeParameter.TypeParameterCharacteristics(), tps, cl.EnclosingModuleDefinition, id,
       new BinaryExpr(cl.Tok, BinaryExpr.Opcode.Neq, new IdentifierExpr(cl.Tok, id), new LiteralExpr(cl.Tok)),
       SubsetTypeDecl.WKind.Special, null, SystemModuleManager.AxiomAttribute()) {
     Contract.Requires(cl != null);
diff --git a/Source/DafnyCore/AST/TypeDeclarations/SubsetTypeDecl.cs b/Source/DafnyCore/AST/TypeDeclarations/SubsetTypeDecl.cs
index d26493ee8d6..23905cb3776 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/SubsetTypeDecl.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/SubsetTypeDecl.cs
@@ -26,7 +26,7 @@ bool RedirectingTypeDecl.ConstraintIsCompilable {
     }
   }
 
-  public SubsetTypeDecl(RangeToken rangeOrigin, Name name, TypeParameter.TypeParameterCharacteristics characteristics, List<TypeParameter> typeArgs, ModuleDefinition module,
+  public SubsetTypeDecl(IOrigin rangeOrigin, Name name, TypeParameter.TypeParameterCharacteristics characteristics, List<TypeParameter> typeArgs, ModuleDefinition module,
     BoundVar id, Expression constraint, WKind witnessKind, Expression witness,
     Attributes attributes)
     : base(rangeOrigin, name, characteristics, typeArgs, module, id.Type, attributes) {
diff --git a/Source/DafnyCore/AST/TypeDeclarations/TopLevelDecl.cs b/Source/DafnyCore/AST/TypeDeclarations/TopLevelDecl.cs
index e001ee55a0a..926ba85da96 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/TopLevelDecl.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/TopLevelDecl.cs
@@ -20,7 +20,7 @@ protected TopLevelDecl(Cloner cloner, TopLevelDecl original, ModuleDefinition pa
     EnclosingModuleDefinition = parent;
   }
 
-  protected TopLevelDecl(RangeToken rangeOrigin, Name name, ModuleDefinition enclosingModule, List<TypeParameter> typeArgs, Attributes attributes, bool isRefining)
+  protected TopLevelDecl(IOrigin rangeOrigin, Name name, ModuleDefinition enclosingModule, List<TypeParameter> typeArgs, Attributes attributes, bool isRefining)
     : base(rangeOrigin, name, attributes, isRefining) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(name != null);
diff --git a/Source/DafnyCore/AST/TypeDeclarations/TopLevelDeclWithMembers.cs b/Source/DafnyCore/AST/TypeDeclarations/TopLevelDeclWithMembers.cs
index f5e945f4bd3..7d3fa2a0a03 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/TopLevelDeclWithMembers.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/TopLevelDeclWithMembers.cs
@@ -87,7 +87,7 @@ public void Extend(TraitDecl parent, InheritanceInformationClass parentInfo, Dic
     }
   }
 
-  protected TopLevelDeclWithMembers(RangeToken rangeOrigin, Name name, ModuleDefinition module,
+  protected TopLevelDeclWithMembers(IOrigin rangeOrigin, Name name, ModuleDefinition module,
     List<TypeParameter> typeArgs, List<MemberDecl> members, Attributes attributes,
     bool isRefining, List<Type>/*?*/ traits = null)
     : base(rangeOrigin, name, module, typeArgs, attributes, isRefining) {
@@ -221,7 +221,7 @@ public void RegisterMembers(ModuleResolver resolver, Dictionary<string, MemberDe
             List<TypeParameter> tyvars = extremePredicate.TypeArgs.ConvertAll(cloner.CloneTypeParam);
 
             // create prefix predicate
-            extremePredicate.PrefixPredicate = new PrefixPredicate(extremePredicate.RangeToken, extraName, extremePredicate.HasStaticKeyword,
+            extremePredicate.PrefixPredicate = new PrefixPredicate(extremePredicate.Origin, extraName, extremePredicate.HasStaticKeyword,
               tyvars, k, formals,
               extremePredicate.Req.ConvertAll(cloner.CloneAttributedExpr),
               cloner.CloneSpecFrameExpr(extremePredicate.Reads),
@@ -248,7 +248,7 @@ public void RegisterMembers(ModuleResolver resolver, Dictionary<string, MemberDe
             var ens = extremeLemma is GreatestLemma
               ? new List<AttributedExpression>()
               : extremeLemma.Ens.ConvertAll(cloner.CloneAttributedExpr);
-            extremeLemma.PrefixLemma = new PrefixLemma(extremeLemma.RangeToken, extraName, extremeLemma.HasStaticKeyword,
+            extremeLemma.PrefixLemma = new PrefixLemma(extremeLemma.Origin, extraName, extremeLemma.HasStaticKeyword,
               extremeLemma.TypeArgs.ConvertAll(cloner.CloneTypeParam), k, formals, extremeLemma.Outs.ConvertAll(f => cloner.CloneFormal(f, false)),
               req, cloner.CloneSpecFrameExpr(extremeLemma.Reads),
               cloner.CloneSpecFrameExpr(extremeLemma.Mod), ens,
diff --git a/Source/DafnyCore/AST/TypeDeclarations/TraitDecl.cs b/Source/DafnyCore/AST/TypeDeclarations/TraitDecl.cs
index eaf9a399c76..760e9959072 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/TraitDecl.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/TraitDecl.cs
@@ -25,7 +25,7 @@ internal void SetUpAsReferenceType(bool isReferenceType) {
   /// This constructor creates a TraitDecl object. However, before the object really functions as a TraitDecl, it is necessary
   /// to call SetUpAsReferenceType, which sets .NonNullTypeDecl (if necessary) and calls NewSelfSynonym().
   /// </summary>
-  public TraitDecl(RangeToken rangeOrigin, Name name, ModuleDefinition module,
+  public TraitDecl(IOrigin rangeOrigin, Name name, ModuleDefinition module,
     List<TypeParameter> typeArgs, [Captured] List<MemberDecl> members, Attributes attributes, bool isRefining, List<Type> /*?*/ traits)
     : base(rangeOrigin, name, module, typeArgs, members, attributes, isRefining, traits) {
   }
diff --git a/Source/DafnyCore/AST/TypeDeclarations/TupleTypeDecl.cs b/Source/DafnyCore/AST/TypeDeclarations/TupleTypeDecl.cs
index 590e4915204..4736a3dbb2d 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/TupleTypeDecl.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/TupleTypeDecl.cs
@@ -34,7 +34,7 @@ public TupleTypeDecl(List<bool> argumentGhostness, ModuleDefinition systemModule
   }
 
   private TupleTypeDecl(ModuleDefinition systemModule, List<TypeParameter> typeArgs, List<bool> argumentGhostness, Attributes attributes)
-    : base(RangeToken.NoToken, new Name(SystemModuleManager.TupleTypeName(argumentGhostness)), systemModule, typeArgs,
+    : base(Dafny.RangeToken.NoToken, new Name(SystemModuleManager.TupleTypeName(argumentGhostness)), systemModule, typeArgs,
       CreateConstructors(typeArgs, argumentGhostness),
       new List<Type>(), new List<MemberDecl>(), attributes, false) {
     Contract.Requires(systemModule != null);
@@ -58,7 +58,7 @@ private static List<TypeParameter> CreateCovariantTypeParameters(int dims) {
     Contract.Requires(0 <= dims);
     var ts = new List<TypeParameter>();
     for (int i = 0; i < dims; i++) {
-      var tp = new TypeParameter(RangeToken.NoToken, new Name("T" + i), TypeParameter.TPVarianceSyntax.Covariant_Strict);
+      var tp = new TypeParameter(Dafny.RangeToken.NoToken, new Name("T" + i), TypeParameter.TPVarianceSyntax.Covariant_Strict);
       tp.NecessaryForEqualitySupportOfSurroundingInductiveDatatype = true;
       ts.Add(tp);
     }
@@ -87,7 +87,7 @@ private static List<DatatypeCtor> CreateConstructors(List<TypeParameter> typeArg
       formals.Add(f);
     }
     string ctorName = SystemModuleManager.TupleTypeCtorName(typeArgs.Count);
-    var ctor = new DatatypeCtor(RangeToken.NoToken, new Name(ctorName), false, formals, null);
+    var ctor = new DatatypeCtor(Dafny.RangeToken.NoToken, new Name(ctorName), false, formals, null);
     return new List<DatatypeCtor>() { ctor };
   }
 
diff --git a/Source/DafnyCore/AST/TypeDeclarations/TypeDeclSynonymInfo.cs b/Source/DafnyCore/AST/TypeDeclarations/TypeDeclSynonymInfo.cs
index ec0bcf82e61..c37baf87657 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/TypeDeclSynonymInfo.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/TypeDeclSynonymInfo.cs
@@ -7,7 +7,7 @@ public class TypeDeclSynonymInfo {
 
   public TypeDeclSynonymInfo(TopLevelDecl d) {
     var thisType = UserDefinedType.FromTopLevelDecl(d.Tok, d);
-    SelfSynonymDecl = new InternalTypeSynonymDecl(d.RangeToken, d.NameNode, TypeParameter.GetExplicitCharacteristics(d),
+    SelfSynonymDecl = new InternalTypeSynonymDecl(d.Origin, d.NameNode, TypeParameter.GetExplicitCharacteristics(d),
       d.TypeArgs, d.EnclosingModuleDefinition, thisType, d.Attributes);
     SelfSynonymDecl.InheritVisibility(d, false);
   }
diff --git a/Source/DafnyCore/AST/TypeDeclarations/TypeSynonymDecl.cs b/Source/DafnyCore/AST/TypeDeclarations/TypeSynonymDecl.cs
index 457fefd4e9b..925daa2e69c 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/TypeSynonymDecl.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/TypeSynonymDecl.cs
@@ -6,7 +6,7 @@ namespace Microsoft.Dafny;
 public class TypeSynonymDecl : TypeSynonymDeclBase, RevealableTypeDecl {
   public override string WhatKind => "type synonym";
 
-  public TypeSynonymDecl(RangeToken rangeOrigin, Name name, TypeParameter.TypeParameterCharacteristics characteristics, List<TypeParameter> typeArgs, ModuleDefinition module, Type rhs, Attributes attributes)
+  public TypeSynonymDecl(IOrigin rangeOrigin, Name name, TypeParameter.TypeParameterCharacteristics characteristics, List<TypeParameter> typeArgs, ModuleDefinition module, Type rhs, Attributes attributes)
     : base(rangeOrigin, name, characteristics, typeArgs, module, rhs, attributes) {
     this.NewSelfSynonym();
   }
@@ -20,7 +20,7 @@ public override string GetDescription(DafnyOptions options) {
 
 public class InternalTypeSynonymDecl : TypeSynonymDeclBase {
   public override string WhatKind { get { return "export-provided type"; } }
-  public InternalTypeSynonymDecl(RangeToken rangeOrigin, Name name, TypeParameter.TypeParameterCharacteristics characteristics, List<TypeParameter> typeArgs, ModuleDefinition module, Type rhs, Attributes attributes)
+  public InternalTypeSynonymDecl(IOrigin rangeOrigin, Name name, TypeParameter.TypeParameterCharacteristics characteristics, List<TypeParameter> typeArgs, ModuleDefinition module, Type rhs, Attributes attributes)
     : base(rangeOrigin, name, characteristics, typeArgs, module, rhs, attributes) {
   }
 
diff --git a/Source/DafnyCore/AST/TypeDeclarations/TypeSynonymDeclBase.cs b/Source/DafnyCore/AST/TypeDeclarations/TypeSynonymDeclBase.cs
index ef5b9f637e3..e1f248b004a 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/TypeSynonymDeclBase.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/TypeSynonymDeclBase.cs
@@ -13,7 +13,7 @@ public bool SupportsEquality {
   }
   public readonly Type Rhs;
 
-  protected TypeSynonymDeclBase(RangeToken rangeOrigin, Name name, TypeParameter.TypeParameterCharacteristics characteristics, List<TypeParameter> typeArgs, ModuleDefinition module, Type rhs, Attributes attributes)
+  protected TypeSynonymDeclBase(IOrigin rangeOrigin, Name name, TypeParameter.TypeParameterCharacteristics characteristics, List<TypeParameter> typeArgs, ModuleDefinition module, Type rhs, Attributes attributes)
     : base(rangeOrigin, name, module, typeArgs, attributes, false) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(name != null);
diff --git a/Source/DafnyCore/AST/TypeDeclarations/ValuetypeDecl.cs b/Source/DafnyCore/AST/TypeDeclarations/ValuetypeDecl.cs
index fdce0dbaf1b..64782ecbbee 100644
--- a/Source/DafnyCore/AST/TypeDeclarations/ValuetypeDecl.cs
+++ b/Source/DafnyCore/AST/TypeDeclarations/ValuetypeDecl.cs
@@ -16,7 +16,7 @@ public class ValuetypeDecl : TopLevelDeclWithMembers {
   public override bool AcceptThis => true;
 
   public ValuetypeDecl(string name, ModuleDefinition module, Func<Type, bool> typeTester, Func<List<Type>, Type> typeCreator /*?*/)
-    : base(RangeToken.NoToken, new Name(name), module, new List<TypeParameter>(), new List<MemberDecl>(), null, false, null) {
+    : base(Dafny.RangeToken.NoToken, new Name(name), module, new List<TypeParameter>(), new List<MemberDecl>(), null, false, null) {
     Contract.Requires(name != null);
     Contract.Requires(module != null);
     Contract.Requires(typeTester != null);
@@ -34,7 +34,7 @@ public ValuetypeDecl(string name, ModuleDefinition module, List<TypeParameter.TP
     if (typeParameterVariance != null) {
       for (int i = 0; i < typeParameterVariance.Count; i++) {
         var variance = typeParameterVariance[i];
-        var tp = new TypeParameter(RangeToken.NoToken, new Name(((char)('T' + i)).ToString()), variance) {
+        var tp = new TypeParameter(Dafny.RangeToken.NoToken, new Name(((char)('T' + i)).ToString()), variance) {
           Parent = this,
           PositionalIndex = i
         };
@@ -45,7 +45,7 @@ public ValuetypeDecl(string name, ModuleDefinition module, List<TypeParameter.TP
 
   public ValuetypeDecl(string name, ModuleDefinition module, List<TypeParameter> typeParameters,
     List<MemberDecl> members, Attributes attributes, Func<Type, bool> typeTester, Func<List<Type>, Type> /*?*/ typeCreator)
-    : base(RangeToken.NoToken, new Name(name), module, typeParameters, members, attributes, false) {
+    : base(Dafny.RangeToken.NoToken, new Name(name), module, typeParameters, members, attributes, false) {
     this.typeTester = typeTester;
     this.typeCreator = typeCreator;
   }
diff --git a/Source/DafnyCore/AST/Types/TypeParameter.cs b/Source/DafnyCore/AST/Types/TypeParameter.cs
index 15b0d8b0e43..0d8aa6c10c7 100644
--- a/Source/DafnyCore/AST/Types/TypeParameter.cs
+++ b/Source/DafnyCore/AST/Types/TypeParameter.cs
@@ -126,7 +126,7 @@ public static List<TPVariance> Variances(List<TypeParameter> typeParameters, boo
 
   public enum EqualitySupportValue { Required, InferredRequired, Unspecified }
   public struct TypeParameterCharacteristics {
-    public RangeToken RangeToken = null;
+    public RangeToken RangeOrigin = null;
     public EqualitySupportValue EqualitySupport;  // the resolver may change this value from Unspecified to InferredRequired (for some signatures that may immediately imply that equality support is required)
     public Type.AutoInitInfo AutoInit;
     public bool HasCompiledValue => AutoInit == Type.AutoInitInfo.CompilableValue;
@@ -186,7 +186,7 @@ public IEnumerable<TopLevelDecl> TypeBoundHeads {
     }
   }
 
-  public TypeParameter(RangeToken rangeOrigin, Name name, TPVarianceSyntax varianceS, TypeParameterCharacteristics characteristics,
+  public TypeParameter(IOrigin rangeOrigin, Name name, TPVarianceSyntax varianceS, TypeParameterCharacteristics characteristics,
     List<Type> typeBounds)
     : base(rangeOrigin, name, null, new List<TypeParameter>(), null, false) {
     Contract.Requires(rangeOrigin != null);
@@ -196,13 +196,13 @@ public TypeParameter(RangeToken rangeOrigin, Name name, TPVarianceSyntax varianc
     TypeBounds = typeBounds;
   }
 
-  public TypeParameter(RangeToken rangeOrigin, Name name, TPVarianceSyntax varianceS)
+  public TypeParameter(IOrigin rangeOrigin, Name name, TPVarianceSyntax varianceS)
     : this(rangeOrigin, name, varianceS, new TypeParameterCharacteristics(false), new List<Type>()) {
     Contract.Requires(rangeOrigin != null);
     Contract.Requires(name != null);
   }
 
-  public TypeParameter(RangeToken tok, Name name, int positionalIndex, ParentType parent)
+  public TypeParameter(IOrigin tok, Name name, int positionalIndex, ParentType parent)
     : this(tok, name, TPVarianceSyntax.NonVariant_Strict) {
     PositionalIndex = positionalIndex;
     Parent = parent;
@@ -215,7 +215,7 @@ public static List<TypeParameter> CloneTypeParameters(List<TypeParameter> typePa
     var cloner = new Cloner();
     return typeParameters.ConvertAll(tp => {
       var typeBounds = tp.TypeBounds.ConvertAll(cloner.CloneType);
-      return new TypeParameter(tp.RangeToken, tp.NameNode, tp.VarianceSyntax, tp.Characteristics, typeBounds);
+      return new TypeParameter(tp.Origin, tp.NameNode, tp.VarianceSyntax, tp.Characteristics, typeBounds);
     });
   }
 
diff --git a/Source/DafnyCore/AST/Types/Types.cs b/Source/DafnyCore/AST/Types/Types.cs
index 423797040a4..c71a1b69ec3 100644
--- a/Source/DafnyCore/AST/Types/Types.cs
+++ b/Source/DafnyCore/AST/Types/Types.cs
@@ -1897,8 +1897,8 @@ public override bool IsSubtypeOf(Type super, bool ignoreTypeArguments, bool igno
 public class SelfType : NonProxyType {
   public TypeParameter TypeArg;
   public Type ResolvedType;
-  public SelfType() : base() {
-    TypeArg = new TypeParameter(RangeToken.NoToken, new Name("selfType"), TypeParameter.TPVarianceSyntax.NonVariant_Strict);
+  public SelfType() {
+    TypeArg = new TypeParameter(Dafny.RangeToken.NoToken, new Name("selfType"), TypeParameter.TPVarianceSyntax.NonVariant_Strict);
   }
 
   [System.Diagnostics.Contracts.Pure]
diff --git a/Source/DafnyCore/AST/Types/UserDefinedType.cs b/Source/DafnyCore/AST/Types/UserDefinedType.cs
index 48df0cc49a1..2dea4e86bad 100644
--- a/Source/DafnyCore/AST/Types/UserDefinedType.cs
+++ b/Source/DafnyCore/AST/Types/UserDefinedType.cs
@@ -68,7 +68,7 @@ public UserDefinedType(IOrigin tok, Expression namePath) {
     this.NamePath = namePath;
   }
   public UserDefinedType(Cloner cloner, UserDefinedType original)
-    : this(cloner.Tok(original.tok), cloner.CloneExpr(original.NamePath)) {
+    : this(cloner.Origin(original.tok), cloner.CloneExpr(original.NamePath)) {
     if (cloner.CloneResolvedFields) {
       ResolvedClass = cloner.GetCloneIfAvailable(original.ResolvedClass);
       TypeArgs = original.TypeArgs.Select(cloner.CloneType).ToList();
diff --git a/Source/DafnyCore/Backends/CSharp/CsharpCodeGenerator.cs b/Source/DafnyCore/Backends/CSharp/CsharpCodeGenerator.cs
index 83715edf02f..d63b0ffc335 100644
--- a/Source/DafnyCore/Backends/CSharp/CsharpCodeGenerator.cs
+++ b/Source/DafnyCore/Backends/CSharp/CsharpCodeGenerator.cs
@@ -726,7 +726,7 @@ bool InvalidType(Type ty, bool refTy) =>
       var typeArgs = TypeParameters(nonGhostTypeArgs);
       var typeParameterSubstMap = nonGhostTypeArgs.ToDictionary(
         tp => tp,
-        tp => new TypeParameter(tp.RangeToken, tp.NameNode.Prepend("_"), tp.VarianceSyntax));
+        tp => new TypeParameter(tp.Origin, tp.NameNode.Prepend("_"), tp.VarianceSyntax));
       var typeSubstMap = nonGhostTypeArgs.ToDictionary(
         tp => tp,
         tp => (Type)new UserDefinedType(tp.tok, typeParameterSubstMap[tp]));
@@ -813,7 +813,7 @@ bool ContainsTyVar(TypeParameter tp, Type ty)
         if (nonGhostTypeArgs.Exists(ty => ContainsTyVar(ty, fromType))) {
           var map = nonGhostTypeArgs.ToDictionary(
             tp => tp,
-            tp => (Type)new UserDefinedType(tp.tok, new TypeParameter(tp.RangeToken, tp.NameNode.Prepend("_"), tp.VarianceSyntax)));
+            tp => (Type)new UserDefinedType(tp.tok, new TypeParameter(tp.Origin, tp.NameNode.Prepend("_"), tp.VarianceSyntax)));
           var to = fromType.Subst(map);
           var downcast = new ConcreteSyntaxTree();
           EmitDowncast(fromType, to, null, downcast).Write(name);
diff --git a/Source/DafnyCore/Backends/GoLang/GoCodeGenerator.cs b/Source/DafnyCore/Backends/GoLang/GoCodeGenerator.cs
index 01f63f53a58..45d77372adf 100644
--- a/Source/DafnyCore/Backends/GoLang/GoCodeGenerator.cs
+++ b/Source/DafnyCore/Backends/GoLang/GoCodeGenerator.cs
@@ -3257,7 +3257,7 @@ protected override void EmitSeqConstructionExpr(SeqConstructionExpr expr, bool i
       wr.Write(", ");
       var fromType = (ArrowType)expr.Initializer.Type.NormalizeExpand();
       var atd = (ArrowTypeDecl)fromType.ResolvedClass;
-      var tParam = new UserDefinedType(expr.tok, new TypeParameter(expr.RangeToken, new Name("X"), TypeParameter.TPVarianceSyntax.NonVariant_Strict));
+      var tParam = new UserDefinedType(expr.tok, new TypeParameter(expr.Origin, new Name("X"), TypeParameter.TPVarianceSyntax.NonVariant_Strict));
       var toType = new ArrowType(expr.tok, atd, new List<Type>() { Type.Int }, tParam);
       var initWr = EmitCoercionIfNecessary(fromType, toType, expr.tok, wr);
       initWr.Append(Expr(expr.Initializer, inLetExprBody, wStmts));
diff --git a/Source/DafnyCore/Backends/SinglePassCodeGenerator/SinglePassCodeGenerator.Statement.cs b/Source/DafnyCore/Backends/SinglePassCodeGenerator/SinglePassCodeGenerator.Statement.cs
index 52053e747ab..c6004552363 100644
--- a/Source/DafnyCore/Backends/SinglePassCodeGenerator/SinglePassCodeGenerator.Statement.cs
+++ b/Source/DafnyCore/Backends/SinglePassCodeGenerator/SinglePassCodeGenerator.Statement.cs
@@ -171,7 +171,7 @@ protected void TrStmt(Statement stmt, ConcreteSyntaxTree wr, ConcreteSyntaxTree
                 && stmtUpdate == assignOrReturnStmt) {
               // Wrap this UpdateStmt with a VarDecl containing this Local that we haven't emitted yet.
               stmts[innerExtractIndex] =
-                new VarDeclStmt(enclosingVarDecl.RangeToken,
+                new VarDeclStmt(enclosingVarDecl.Origin,
                   new List<LocalVariable>() { locals[0] },
                   (AssignStatement)stmts[innerExtractIndex]);
             }
diff --git a/Source/DafnyCore/Backends/SinglePassCodeGenerator/SinglePassCodeGenerator.cs b/Source/DafnyCore/Backends/SinglePassCodeGenerator/SinglePassCodeGenerator.cs
index 86a7d5a793d..c00b2c0fc01 100644
--- a/Source/DafnyCore/Backends/SinglePassCodeGenerator/SinglePassCodeGenerator.cs
+++ b/Source/DafnyCore/Backends/SinglePassCodeGenerator/SinglePassCodeGenerator.cs
@@ -2754,7 +2754,7 @@ private void CompileFunction(Function f, IClassWriter cw, bool lookasideBody) {
         IVariable accVar = null;
         if (f.IsTailRecursive) {
           if (f.IsAccumulatorTailRecursive) {
-            accVar = new LocalVariable(f.RangeToken, "_accumulator", f.ResultType, false) {
+            accVar = new LocalVariable(f.Origin, "_accumulator", f.ResultType, false) {
               type = f.ResultType
             };
             var resultType = f.ResultType.NormalizeToAncestorType();
@@ -2847,7 +2847,7 @@ private void HandleCompilingMainMethod(Program program, Method m, IClassWriter c
         var ty = UserDefinedType.FromTopLevelDeclWithAllBooleanTypeParameters(m.EnclosingClass);
         LocalVariable receiver = null;
         if (!m.IsStatic) {
-          receiver = new LocalVariable(m.RangeToken, "b", ty, false) {
+          receiver = new LocalVariable(m.Origin, "b", ty, false) {
             type = ty
           };
           if (m.EnclosingClass is ClassLikeDecl) {
@@ -5064,7 +5064,7 @@ void ReturnBoolLiteral(ConcreteSyntaxTree writer, bool value) {
         baseType = baseTypeVarDecl.Type;
       } else {
         baseType = ((NewtypeDecl)declWithConstraints).BaseType;
-        baseTypeVarDecl = new BoundVar(declWithConstraints.RangeToken, "_base", baseType);
+        baseTypeVarDecl = new BoundVar(declWithConstraints.Origin, "_base", baseType);
       }
       baseType = baseType.NormalizeExpandKeepConstraints();
       var baseTypeVar = new IdentifierExpr(declWithConstraints.tok, baseTypeVarDecl);
diff --git a/Source/DafnyCore/CompileNestedMatch/MatchAst.cs b/Source/DafnyCore/CompileNestedMatch/MatchAst.cs
index a8d95233063..9e3a7b08339 100644
--- a/Source/DafnyCore/CompileNestedMatch/MatchAst.cs
+++ b/Source/DafnyCore/CompileNestedMatch/MatchAst.cs
@@ -92,7 +92,7 @@ void ObjectInvariant() {
     Contract.Invariant(cce.NonNullElements(Arguments));
   }
 
-  public MatchCase(IOrigin tok, DatatypeCtor ctor, [Captured] List<BoundVar> arguments) {
+  protected MatchCase(IOrigin tok, DatatypeCtor ctor, [Captured] List<BoundVar> arguments) {
     Contract.Requires(tok != null);
     Contract.Requires(ctor != null);
     Contract.Requires(cce.NonNullElements(arguments));
@@ -142,7 +142,7 @@ public MatchStmt(Cloner cloner, MatchStmt original) : base(cloner, original) {
     }
   }
 
-  public MatchStmt(RangeToken rangeOrigin, Expression source, [Captured] List<MatchCaseStmt> cases,
+  public MatchStmt(IOrigin rangeOrigin, Expression source, [Captured] List<MatchCaseStmt> cases,
     bool usesOptionalBraces, MatchingContext context = null)
     : base(rangeOrigin) {
     Contract.Requires(rangeOrigin != null);
@@ -154,7 +154,7 @@ public MatchStmt(RangeToken rangeOrigin, Expression source, [Captured] List<Matc
     Context = context is null ? new HoleCtx() : context;
   }
 
-  public MatchStmt(RangeToken rangeOrigin, Expression source, [Captured] List<MatchCaseStmt> cases,
+  public MatchStmt(IOrigin rangeOrigin, Expression source, [Captured] List<MatchCaseStmt> cases,
     bool usesOptionalBraces, Attributes attrs, MatchingContext context = null)
     : base(rangeOrigin, attrs) {
     Contract.Requires(rangeOrigin != null);
@@ -250,9 +250,9 @@ void ObjectInvariant() {
   public override IEnumerable<INode> Children => body;
   public override IEnumerable<INode> PreResolveChildren => Children;
 
-  public MatchCaseStmt(RangeToken rangeOrigin, DatatypeCtor ctor, bool fromBoundVar, [Captured] List<BoundVar> arguments, [Captured] List<Statement> body, Attributes attrs = null)
-    : base(rangeOrigin.StartToken, ctor, arguments) {
-    RangeToken = rangeOrigin;
+  public MatchCaseStmt(IOrigin rangeOrigin, DatatypeCtor ctor, bool fromBoundVar, [Captured] List<BoundVar> arguments, [Captured] List<Statement> body, Attributes attrs = null)
+    : base(rangeOrigin, ctor, arguments) {
+    RangeOrigin = rangeOrigin;
     Contract.Requires(tok != null);
     Contract.Requires(ctor != null);
     Contract.Requires(cce.NonNullElements(arguments));
diff --git a/Source/DafnyCore/CompileNestedMatch/MatchFlattener.cs b/Source/DafnyCore/CompileNestedMatch/MatchFlattener.cs
index d915cb3e9cf..40a762241f3 100644
--- a/Source/DafnyCore/CompileNestedMatch/MatchFlattener.cs
+++ b/Source/DafnyCore/CompileNestedMatch/MatchFlattener.cs
@@ -126,7 +126,7 @@ private Statement CompileNestedMatchStmt(NestedMatchStmt nestedMatchStmt) {
         return AssertStmt.CreateErrorAssert(nestedMatchStmt, NoCasesMessage);
       }
 
-      return new MatchStmt(nestedMatchStmt.RangeToken, nestedMatchStmt.Source, new List<MatchCaseStmt>(), nestedMatchStmt.UsesOptionalBraces, nestedMatchStmt.Attributes);
+      return new MatchStmt(nestedMatchStmt.Origin, nestedMatchStmt.Source, new List<MatchCaseStmt>(), nestedMatchStmt.UsesOptionalBraces, nestedMatchStmt.Attributes);
     }
 
     if (compiledMatch.Node is Statement statement) {
@@ -399,7 +399,7 @@ private CaseBody CompileHeadsContainingConstructor(MatchCompilationState mti, Ma
         args.Add(literalExpr);
         c.Attributes = new Attributes("split", args, c.Attributes);
       }
-      var newMatchStmt = new MatchStmt(nestedMatchStmt.RangeToken, headMatchee, newMatchCaseStmts, true, mti.Attributes, context);
+      var newMatchStmt = new MatchStmt(nestedMatchStmt.Origin, headMatchee, newMatchCaseStmts, true, mti.Attributes, context);
       newMatchStmt.IsGhost |= mti.CodeContext.IsGhost;
       return new CaseBody(null, newMatchStmt);
     }
@@ -414,7 +414,7 @@ private MatchCase CreateMatchCase(IOrigin tok, DatatypeCtor ctor, List<BoundVar>
     var cloner = new Cloner(false, true);
     if (bodyContainer.Node is Statement statement) {
       var body = UnboxStmt(statement).Select(stmt => cloner.CloneStmt(stmt, false)).ToList();
-      newMatchCase = new MatchCaseStmt(tok.ToRange(), ctor, fromBoundVar, freshPatBV, body, bodyContainer.Attributes);
+      newMatchCase = new MatchCaseStmt(tok, ctor, fromBoundVar, freshPatBV, body, bodyContainer.Attributes);
     } else {
       var body = (Expression)(bodyContainer.Node);
       var attrs = bodyContainer.Attributes;
@@ -523,7 +523,7 @@ private CaseBody CreateIfElseIfChain(MatchCompilationState mti, MatchingContext
     if (blocks.Count == 0) {
       if (defaultBlock?.Node is Statement stmt) {
         // Ensures the statements are wrapped in braces
-        return new CaseBody(null, BlockStmtOfCStmt(stmt.RangeToken, stmt));
+        return new CaseBody(null, BlockStmtOfCStmt(stmt.Origin, stmt));
       }
 
       return defaultBlock;
@@ -533,7 +533,7 @@ private CaseBody CreateIfElseIfChain(MatchCompilationState mti, MatchingContext
     blocks = blocks.Skip(1).ToList();
 
     var tok = matchee.Tok;
-    var range = matchee.Tok.ToRange();
+    var range = matchee.Tok;
     var guard = new BinaryExpr(mti.Match.Tok, BinaryExpr.Opcode.Eq, matchee, currBlock.Item1) {
       ResolvedOp = BinaryExpr.ResolvedOpcode.EqCommon,
       Type = Type.Bool
@@ -584,7 +584,7 @@ record CaseBody(IOrigin Tok, Node Node, Attributes Attributes = null);
 
   private CaseBody PackBody(IOrigin tok, PatternPath path) {
     if (path is StmtPatternPath br) {
-      return new CaseBody(tok, new BlockStmt(tok.ToRange(), br.Body.ToList()), br.Attributes);
+      return new CaseBody(tok, new BlockStmt(tok, br.Body.ToList()), br.Attributes);
     }
 
     if (path is ExprPatternPath) {
@@ -602,14 +602,14 @@ private List<Statement> UnboxStmt(Statement statement) {
     return new List<Statement>() { statement };
   }
 
-  private BlockStmt BlockStmtOfCStmt(RangeToken rangeOrigin, Statement stmt) {
+  private BlockStmt BlockStmtOfCStmt(IOrigin rangeToken, Statement stmt) {
     if (stmt is BlockStmt) {
       return (BlockStmt)stmt;
     }
 
     var stmts = new List<Statement>();
     stmts.Add(stmt);
-    return new BlockStmt(rangeOrigin, stmts);
+    return new BlockStmt(rangeToken, stmts);
   }
 
   private class MatchCompilationState {
@@ -710,12 +710,12 @@ private PatternPath LetBind(IdPattern var, Expression genExpr, PatternPath bodyP
         return stmtPath;
       }
 
-      var caseLocal = new LocalVariable(var.RangeToken, name, type, isGhost) {
+      var caseLocal = new LocalVariable(var.Origin, name, type, isGhost) {
         type = type
       };
-      var casePattern = new CasePattern<LocalVariable>(caseLocal.RangeToken.EndToken, caseLocal);
+      var casePattern = new CasePattern<LocalVariable>(caseLocal.Origin.EndToken, caseLocal);
       casePattern.AssembleExpr(new List<Type>());
-      var caseLet = new VarDeclPattern(caseLocal.RangeToken, casePattern, expr, false) {
+      var caseLet = new VarDeclPattern(caseLocal.Origin, casePattern, expr, false) {
         IsGhost = isGhost
       };
 
diff --git a/Source/DafnyCore/CoverageReport/CoverageReport.cs b/Source/DafnyCore/CoverageReport/CoverageReport.cs
index 3271f8f063b..9b5db49f03b 100644
--- a/Source/DafnyCore/CoverageReport/CoverageReport.cs
+++ b/Source/DafnyCore/CoverageReport/CoverageReport.cs
@@ -40,7 +40,7 @@ public CoverageReport(string name, string units, string suffix, Program program)
   /// <summary>
   /// Assign a coverage label to the code indicated by the <param name="span"></param> range token.
   /// </summary>
-  public void LabelCode(RangeToken span, CoverageLabel label) {
+  public void LabelCode(IOrigin span, CoverageLabel label) {
     Contract.Assert(labelsByFile.ContainsKey(span.Uri));
     var labeledFile = labelsByFile[span.Uri];
     var coverageSpan = new CoverageSpan(span, label);
diff --git a/Source/DafnyCore/CoverageReport/CoverageSpan.cs b/Source/DafnyCore/CoverageReport/CoverageSpan.cs
index a6bef7345a2..89ac4995eaf 100644
--- a/Source/DafnyCore/CoverageReport/CoverageSpan.cs
+++ b/Source/DafnyCore/CoverageReport/CoverageSpan.cs
@@ -1,4 +1,3 @@
-#nullable disable
 using System;
 using System.Diagnostics.Contracts;
 
@@ -6,10 +5,10 @@ namespace Microsoft.Dafny;
 
 public class CoverageSpan : IComparable<CoverageSpan> {
 
-  public readonly RangeToken Span;
+  public readonly IOrigin Span;
   public readonly CoverageLabel Label;
 
-  public CoverageSpan(RangeToken span, CoverageLabel label) {
+  public CoverageSpan(IOrigin span, CoverageLabel label) {
     Contract.Assert(span.Uri != null);
     Contract.Assert(span.StartToken != null);
     Contract.Assert(span.EndToken != null);
diff --git a/Source/DafnyCore/Dafny.atg b/Source/DafnyCore/Dafny.atg
index 2568f369a93..be0dcef0c55 100644
--- a/Source/DafnyCore/Dafny.atg
+++ b/Source/DafnyCore/Dafny.atg
@@ -227,7 +227,7 @@ Dafny
                                    includedFile = Path.Combine(basePath, includedFile);
                                  }
                                  var oneInclude = new Include(t, parsedFile, new Uri(Path.GetFullPath(includedFile)), theOptions);
-                                 oneInclude.RangeToken = new RangeToken(includeStartToken, t);
+                                 oneInclude.RangeOrigin = new RangeToken(includeStartToken, t);
                                  theModule.Includes.Add(oneInclude);
                                }
                             .)
@@ -236,7 +236,7 @@ Dafny
     TopDecl<theModule, /* isTopLevel */ true, ref attrs> }
   (. CheckNoAttributes(ref attrs); .)
   (. 
-    theModule.RangeToken = new RangeToken(fileStartToken.Next, t);
+    theModule.RangeOrigin = new RangeToken(fileStartToken.Next, t);
   .)
   SYNC
   EOF
@@ -308,7 +308,7 @@ SubModuleDecl<DeclModifierData dmod, ModuleDefinition parent, out ModuleDecl sub
   ( ModuleDefinition<dmod, parent, out submodule>
   | ModuleImport<parent, out submodule>
   | ModuleExport<parent, out submodule>
-    (. if (isTopLevel) SemErr(ErrorId.p_superfluous_export, submodule.RangeToken,
+    (. if (isTopLevel) SemErr(ErrorId.p_superfluous_export, submodule.Origin,
           "There is no point to an export declaration at the top level");
     .)
   )
@@ -331,7 +331,7 @@ ModuleDefinition<DeclModifierData dmod, ModuleDefinition parent, out ModuleDecl
    { Attribute<ref dmod.Attributes> }            (. ApplyOptionsFromAttributes(dmod.Attributes); .)
    ModuleQualifiedName<out var names>
    (. var name = names[^1];
-      prefixIds = names.GetRange(0,names.Count-1).Select(n => n.StartToken).ToList();
+      prefixIds = names.GetRange(0,names.Count-1).Select(n => (IOrigin)n.StartToken).ToList();
    .)
 
    [ "refines" ModuleQualifiedName<out idRefined> (. implementationKind = ImplementationKind.Refinement; .)
@@ -348,9 +348,9 @@ ModuleDefinition<DeclModifierData dmod, ModuleDefinition parent, out ModuleDecl
    "}"
    (. CheckNoAttributes(ref attrs); .)
     (.
-      module.RangeToken = new RangeToken(dmod.FirstToken, t);
+      module.RangeOrigin = new RangeToken(dmod.FirstToken, t);
       submodule = new LiteralModuleDecl(theOptions, module, parent, Guid.NewGuid());
-      submodule.RangeToken = module.RangeToken;
+      submodule.RangeOrigin =module.Origin;
       theOptions = dafnyOptionsBackup;
     .)
   .
@@ -450,7 +450,7 @@ ModuleExport<ModuleDefinition parent, out ModuleDecl submodule>
      Name name;
      if (exportId.val == "export" || exportId.val == parent.Name) {
        isDefault = true;
-       name = new Name(exportId.ToRange(), parent.Name);
+       name = new Name(exportId, parent.Name);
      } else {
        name = new Name(exportId);
      }
@@ -478,7 +478,7 @@ ExportSignature<bool opaque, out ExportSignature exsig>
      } else {
        exsig = new ExportSignature(prefix, prefix.val, opaque);
      }
-     exsig.RangeToken = new RangeToken(startToken, t);
+     exsig.RangeOrigin = new RangeToken(startToken, t);
   .)
   .
 
@@ -900,7 +900,7 @@ GIdentType<bool allowGhostKeyword, bool allowNewKeyword, bool allowNameOnlyKeywo
     )
   }
   IdentType<out var id, out var originalId, out ty, false> 
-                                (. range = new RangeToken(startToken, ty.EndToken);
+                                (. range = new RangeToken(startToken, ty.EndToken, id);
                                    name = new Name(id);
                                 .)
   .
@@ -960,7 +960,7 @@ IdentTypeOptional<out BoundVar var>
      // Also a SetComprehension would be the wrong type in a slices-by-length construct.
   ]
   (. var = new BoundVar(name.Tok, name.Value, ty) {
-       RangeToken = new RangeToken(name.StartToken, t)
+       RangeOrigin = new RangeToken(name.StartToken, t)
      }; .)
   .
 
@@ -998,7 +998,7 @@ TypeIdentOptional<out RangeToken/*!*/ range, out Name/*!*/ identName, out Type/*
     Type<out ty>
     ParameterDefaultValue<true, out defaultValue>
   )
-  (. range = new RangeToken(beforeStartToken.Next, t);
+  (. range = new RangeToken(beforeStartToken.Next, t, nameToken);
      if (nameToken != null) {
        identName = new Name(nameToken);
        isNameOnly = nameonlyToken != null;
@@ -1123,7 +1123,7 @@ TypeParameterCharacteristics<ref TypeParameter.TypeParameterCharacteristics char
   { ","
     TPCharOption<ref characteristics>
   }
-  ")" (. characteristics.RangeToken = new RangeToken(startToken, t); .)
+  ")" (. characteristics.RangeOrigin = new RangeToken(startToken, t); .)
   .
 
 TPCharOption<ref TypeParameter.TypeParameterCharacteristics characteristics>
@@ -1253,7 +1253,7 @@ MethodDecl<DeclModifierData dmod, bool allowConstructor, out Method/*!*/ m>
   ]
   (. var range = new RangeToken(dmod.FirstToken, t);
      if (isConstructor) {
-       m = new Constructor(range, hasName ? name : new Name(dmod.FirstToken.ToRange(), "_ctor"), dmod.IsGhost, typeArgs, ins,
+       m = new Constructor(range, hasName ? name : new Name(dmod.FirstToken, "_ctor"), dmod.IsGhost, typeArgs, ins,
                            req, new Specification<FrameExpression>(reads, readsAttrs), 
                            new Specification<FrameExpression>(mod, modAttrs), ens, 
                            new Specification<Expression>(dec, decAttrs), 
@@ -1296,23 +1296,25 @@ RequiresClause<.List<AttributedExpression> req, bool allowLabel.>
                    Token first = t;
                    Attributes attrs = null;
                    Expression e;
+                   Token keyword = t;
                  .)
   { Attribute<ref attrs> }
   [ IF(IsLabel(allowLabel))
     LabelName<out lbl> ":"
   ]
   Expression<out e, false, false>
-  OldSemi       (. req.Add(new AttributedExpression(e, lbl == null ? null : new AssertLabel(lbl, lbl.val), attrs)); .)
+  OldSemi       (. req.Add(new AttributedExpression(e.Origin.WithCenter(e.StartToken), e, lbl == null ? null : new AssertLabel(lbl, lbl.val), attrs)); .)
   .
 
 /*------------------------------------------------------------------------*/
 EnsuresClause<.List<AttributedExpression> ens, bool allowLambda.>
 = "ensures"     (. Expression e;
                    Attributes attrs = null;
+                   Token keyword = t;
                  .)
   { Attribute<ref attrs> }
   Expression<out e, false, allowLambda>
-    OldSemi       (. ens.Add(new AttributedExpression(e, attrs)); .)
+    OldSemi       (. ens.Add(new AttributedExpression(e.Origin.WithCenter(e.StartToken), e, attrs)); .)
   .
 
 /*------------------------------------------------------------------------*/
@@ -1357,9 +1359,10 @@ ReadsClause<.List<FrameExpression/*!*/>/*!*/ reads, ref Attributes attrs,
 InvariantClause<. List<AttributedExpression> invariants.> =
   "invariant"                                   (. Attributes attrs = null;
                                                    Expression e;
+                                                   Token keyword = t;
                                                 .)
   { Attribute<ref attrs> }
-  Expression<out e, false, true>                (. invariants.Add(new AttributedExpression(e, attrs)); .)
+  Expression<out e, false, true>                (. invariants.Add(new AttributedExpression(e.Origin.WithCenter(e.StartToken), e, attrs)); .)
   OldSemi
   .
 
@@ -1418,16 +1421,14 @@ Formals<.bool incoming, bool allowGhostKeyword, bool allowNewKeyword, bool allow
     { Attribute<ref attrs> }
     GIdentType<allowGhostKeyword, allowNewKeyword, incoming, allowOlderKeyword, out range, out name, out ty, out isGhost, out isOld, out isNameOnly, out isOlder>
     ParameterDefaultValue<incoming, out defaultValue>
-                 (. formals.Add(new Formal(name.Tok, name.Value, ty, incoming, isGhost, defaultValue, attrs, isOld, isNameOnly, isOlder)
-                        { RangeToken = defaultValue != null ? new RangeToken(range.StartToken, defaultValue.EndToken) : range }
-                    ); .)
+                 (. var formalRange = defaultValue != null ? range.WithEnd(defaultValue.EndToken) : range;
+                    formals.Add(new Formal(formalRange, name.Value, ty, incoming, isGhost, defaultValue, attrs, isOld, isNameOnly, isOlder)); .)
     { ","
       { Attribute<ref attrs> }
       GIdentType<allowGhostKeyword, allowNewKeyword, incoming, allowOlderKeyword, out range, out name, out ty, out isGhost, out isOld, out isNameOnly, out isOlder>
       ParameterDefaultValue<incoming, out defaultValue>
-                 (. formals.Add(new Formal(name.Tok, name.Value, ty, incoming, isGhost, defaultValue, attrs, isOld, isNameOnly, isOlder)
-                        { RangeToken = defaultValue != null ? new RangeToken(range.StartToken, defaultValue.EndToken) : range }
-                    ); .)
+                 (. var formalRange2 = defaultValue != null ? range.WithEnd(defaultValue.EndToken) : range;
+                    formals.Add(new Formal(formalRange2, name.Value, ty, incoming, isGhost, defaultValue, attrs, isOld, isNameOnly, isOlder)); .)
     }
   ]
   ")"
@@ -1449,21 +1450,17 @@ ParameterDefaultValue<bool incoming, out Expression defaultValue>
 /*------------------------------------------------------------------------*/
 FormalsOptionalIds<.List<Formal/*!*/>/*!*/ formals.>
 = (. Contract.Requires(cce.NonNullElements(formals));
-     RangeToken/*!*/ range;  Type/*!*/ ty;  Name/*!*/ name;  bool isGhost;  Expression/*?*/ defaultValue;
+     Type/*!*/ ty;  Name/*!*/ name;  bool isGhost;  Expression/*?*/ defaultValue;
      bool isNameOnly;
      Attributes attributes;
   .)
   "("
   [
-    TypeIdentOptional<out range, out name, out ty, out isGhost, out defaultValue, out isNameOnly, out attributes>
-            (. formals.Add(new Formal(name.Tok, name.Value, ty, true, isGhost, defaultValue, attributes, false, isNameOnly) 
-                    { RangeToken = range }
-               ); 
+    TypeIdentOptional<out var origin, out name, out ty, out isGhost, out defaultValue, out isNameOnly, out attributes>
+            (. formals.Add(new Formal(origin, name.Value, ty, true, isGhost, defaultValue, attributes, false, isNameOnly));
             .)
-    { "," TypeIdentOptional<out range, out name, out ty, out isGhost, out defaultValue, out isNameOnly, out attributes>
-            (. formals.Add(new Formal(name.Tok, name.Value, ty, true, isGhost, defaultValue, attributes, false, isNameOnly)
-                    { RangeToken = range }
-               ); 
+    { "," TypeIdentOptional<out origin, out name, out ty, out isGhost, out defaultValue, out isNameOnly, out attributes>
+            (. formals.Add(new Formal(origin, name.Value, ty, true, isGhost, defaultValue, attributes, false, isNameOnly));
             .)
     }
   ]
@@ -1481,7 +1478,7 @@ TypeAndToken<out Token tok, out Type ty, bool inExpressionContext>
      Contract.Ensures(Contract.ValueAtReturn(out ty) != null);
      tok = Token.NoToken;
      ty = new BoolType();  /*keep compiler happy*/
-     IOrigin startToken = null;
+     Token startToken = null;
      List<Type> gt;
      List<Type> tupleArgTypes = null;
      List<Token> argumentGhostTokens = null;
@@ -1569,7 +1566,7 @@ TypeAndToken<out Token tok, out Type ty, bool inExpressionContext>
   | NamedType<out ty, out tok, inExpressionContext>
   )
   (. startToken = startToken ?? ty.StartToken ?? tok;
-     ty.RangeToken = new RangeToken(startToken, t);
+     ty.RangeOrigin = new RangeToken(startToken, t);
   .)
   [ (. int arrowKind = 0; /* 0: any, 1: partial, 2: total */
        Type t2;
@@ -1600,7 +1597,7 @@ TypeAndToken<out Token tok, out Type ty, bool inExpressionContext>
            ty = new UserDefinedType(tok, ArrowType.TotalArrowTypeName(arity), gt);
          }
        }
-       ty.RangeToken = new RangeToken(startToken, t);
+       ty.RangeOrigin = new RangeToken(startToken, t);
     .)
   ]
   .
@@ -1637,7 +1634,7 @@ TupleType<.out Type ty, out Token tok, out List<Type> tupleArgTypes, out List<To
 
 /*------------------------------------------------------------------------*/
 NamedType<.out Type ty, out Token tok, bool inExpressionContext.> =
-  (. Expression e; IOrigin startToken = null; .)
+  (. Expression e; Token startToken = null; .)
   NameSegmentForTypeName<out e, inExpressionContext>  (. tok = t; startToken = e.StartToken; .)
   { "."
     TypeNameOrCtorSuffix<out tok>       (. List<Type> typeArgs; .)
@@ -1645,7 +1642,7 @@ NamedType<.out Type ty, out Token tok, bool inExpressionContext.> =
     (. e = new ExprDotName(tok, e, tok.val, typeArgs); .)
   }
   (. ty = new UserDefinedType(e.tok, e);
-     ty.RangeToken = new RangeToken(startToken, t);
+     ty.RangeOrigin = new RangeToken(startToken, t);
    .)
   .
 
@@ -1749,8 +1746,7 @@ FunctionDecl<DeclModifierData dmod, out Function/*!*/ f>
          "("
            GIdentType<false, false, false, false, out var range2, out var resultName, out var ty, out var resultIsGhost, out var isOld, out var isNameOnly, out var isOlder>
            (. Contract.Assert(!resultIsGhost && !isOld && !isNameOnly && !isOlder);
-              result = new Formal(resultName.Tok, resultName.Value, ty, false, false, null, null, false)
-                { RangeToken = range2 };
+              result = new Formal(range2, resultName.Value, ty, false, false, null, null, false);
            .)
          ")"
          | Type<out returnType>
@@ -2054,8 +2050,7 @@ PredicateResult<string name, out Formal result>
           if (ty is not BoolType) {
             SemErr(ErrorId.p_predicate_return_type_must_be_bool, new RangeToken(ty.StartToken, t), $"{name} return type should be bool, got {ty}");
           }
-          result = new Formal(nameId.Tok, nameId.Value, ty, false, false, null, attributes, false)
-            { RangeToken = range };
+          result = new Formal(range, nameId.Value, ty, false, false, null, attributes, false);
        .)
      ")"
      | Type<out returnType> (. SemErr(ErrorId.p_no_return_type_for_predicate, new RangeToken(returnType.StartToken, t), $"{name}s do not have an explicitly declared return type; it is always bool. Unless you want to name the result: ': (result: bool)'"); .)
@@ -2231,7 +2226,7 @@ LabeledStmt<out Statement s>
   OneStmt<out s>
   (. s.Labels = new LList<Label>(new Label(id, id.val), s.Labels);
      s.PostLabelToken = s.StartToken;
-     s.RangeToken = new RangeToken(labelToken, t);
+     s.RangeOrigin = new RangeToken(labelToken, t);
   .)
   .
 
@@ -2318,9 +2313,10 @@ AssignStatement<out Statement/*!*/ s>
      Expression e;
      AssignmentRhs r;
      BlockStmt proof = null;
-     IOrigin x = Token.NoToken;
+     Token center = null;
+     Token byKeyword = null;
      Token endTok = Token.NoToken;
-     IOrigin startToken = Token.NoToken;
+     Token startToken = Token.NoToken;
      Attributes attrs = null;
      Attributes tokenAttrs = null;
      AttributedToken suchThatAssume = null;
@@ -2330,22 +2326,22 @@ AssignStatement<out Statement/*!*/ s>
      ExprRhs exceptionRhs = null;
      Token endToken = Token.NoToken;
   .)
-( Lhs<out e>                       (. x = e.tok; startToken = e.StartToken; endToken = t; .)
+( Lhs<out e>                       (. center = e.Center; startToken = e.StartToken; endToken = t; .)
   ( 
                                    (. lhss.Add(e); .)
     { "," Lhs<out e>               (. lhss.Add(e); .)
     }
-    ( ":="                         (. x = t; .)
+    ( ":="                         (. center = t; .)
       Rhs<out r>                   (. rhss.Add(r); .)
       { "," Rhs<out r>             (. rhss.Add(r); .)
       }
-    | ":|"                         (. x = t; .)
+    | ":|"                         (. center = t; .)
       [ IF(la.kind == _assume)     /* an Expression can also begin with an "assume", so this says to resolve it to pick up any "assume" here */
         "assume"                      (. var tok = t; .)
         { Attribute<ref tokenAttrs> } (. suchThatAssume = new AttributedToken(tok, tokenAttrs); .)
       ]
       Expression<out suchThat, false, true>
-    | ":-"                         (. x = t; .)
+    | ":-"                         (. center = t; .)
       [ IF(IsAssumeTypeKeyword(la))   /* an Expression can also begin with these keywords, so this says to resolve it to pick up the keyword here */
         ("expect"|"assert"|"assume")  (. var tok = t; .)
         { Attribute<ref tokenAttrs> } (. keywordToken = new AttributedToken(tok, tokenAttrs); .)
@@ -2356,21 +2352,21 @@ AssignStatement<out Statement/*!*/ s>
       }
     )
     (
-      "by" BlockStmt<out proof, out _, out _>
+      "by" BlockStmt<out proof, out _, out _> (. byKeyword = t; .)
     | ";"
     )
   | ":"                            (. SemErr(ErrorId.p_invalid_colon, new RangeToken(startToken, t), "invalid statement beginning here (is a 'label' keyword missing? or a 'const' or 'var' keyword?)"); .)
   | { Attribute<ref attrs> }       (. endToken = t; .)
     (
-      "by" BlockStmt<out proof, out _, out _>
+      "by" BlockStmt<out proof, out _, out _> (. byKeyword = t; .)
     | ";"
-    )                              (. endTok = t; rhss.Add(new ExprRhs(e, attrs) { RangeToken = new RangeToken(e.StartToken, endToken) }); .)
+    )                              (. endTok = t; rhss.Add(new ExprRhs(e, attrs) { RangeOrigin = new RangeToken(e.StartToken, endToken) }); .)
   | { Attribute<ref attrs> }       (. endToken = t; .)
-                                   (. endTok = t; rhss.Add(new ExprRhs(e, attrs) { RangeToken = new RangeToken(e.StartToken, endToken) });
+                                   (. endTok = t; rhss.Add(new ExprRhs(e, attrs) { RangeOrigin = new RangeToken(e.StartToken, endToken) });
                                       SemErr(ErrorId.p_missing_semicolon, new RangeToken(startToken, t), "missing semicolon at end of statement");
                                    .)   
   )
-| ":-"                             (. x = t; startToken = t; .)
+| ":-"                             (. center = t; startToken = t; .)
    [ IF(IsAssumeTypeKeyword(la))      /* an Expression can also begin with these keywords, so this says to resolve it to pick up the keyword here */
       ("expect"|"assert"|"assume")    (. var tok = t; .)
       { Attribute<ref tokenAttrs> }   (. keywordToken = new AttributedToken(tok, tokenAttrs); .)
@@ -2380,25 +2376,27 @@ AssignStatement<out Statement/*!*/ s>
    { "," Rhs<out r>                (. rhss.Add(r); .)
    }
    (
-     "by" BlockStmt<out proof, out _, out _>
+     "by" BlockStmt<out proof, out _, out _> (. byKeyword = t; .)
    | ";"                           (. endTok = t; .)
    )                           
 )
-  (. var rangeToken = new RangeToken(startToken, t);
+  (. 
+     var assignmentOrigin = new RangeToken(startToken, t, center);
+     var byOrigin = new RangeToken(startToken, t, byKeyword);
      if (suchThat != null) {
-       s = new AssignSuchThatStmt(rangeToken, lhss, suchThat, suchThatAssume, null);
+       s = new AssignSuchThatStmt(assignmentOrigin, lhss, suchThat, suchThatAssume, null);
      } else if (exceptionRhs != null) {
-       s = new AssignOrReturnStmt(rangeToken, lhss, exceptionRhs, keywordToken, rhss);
+       s = new AssignOrReturnStmt(assignmentOrigin, lhss, exceptionRhs, keywordToken, rhss);
        if (proof != null) {
-         s = new BlockByProofStmt(rangeToken, proof, s);
+         s = new BlockByProofStmt(byOrigin, proof, s);
        }
      } else {
        if (lhss.Count == 0 && rhss.Count == 0) {
-         s = new BlockStmt(rangeToken, new List<Statement>()); // error, give empty statement
+         s = new BlockStmt(assignmentOrigin, new List<Statement>()); // error, give empty statement
        } else {
-         s = new AssignStatement(rangeToken, lhss, rhss);
+         s = new AssignStatement(assignmentOrigin, lhss, rhss);
          if (proof != null) {
-           s = new BlockByProofStmt(rangeToken, proof, s);
+           s = new BlockByProofStmt(byOrigin, proof, s);
          }
        }
      }
@@ -2416,7 +2414,7 @@ Rhs<out AssignmentRhs r>
      List<Expression> display = null;
      r = dummyRhs;  // to please compiler
      Attributes attrs = null;
-     IOrigin startToken = null;
+     Token startToken = null;
   .)
   ( IF(la.val == "new")
     "new"                              (. newToken = t; startToken = t; .)
@@ -2445,7 +2443,7 @@ Rhs<out AssignmentRhs r>
   | Expression<out e, false, true>     (. r = new ExprRhs(e); startToken = e.StartToken; .)
   )
   { Attribute<ref attrs> }             (. r.Attributes = attrs;
-                                          r.RangeToken = new RangeToken(startToken ?? t, t); .)
+                                          r.RangeOrigin = new RangeToken(startToken ?? t, t); .)
   .
 
 /*------------------------------------------------------------------------*/
@@ -2544,27 +2542,27 @@ VarDeclStatement<.out Statement/*!*/ s.>
        var lhsExprs = new List<Expression>();
        if (isGhost || (rhss.Count == 0 && exceptionRhs == null && suchThat == null)) { // explicitly ghost or no init
          foreach (var lhs in lhss) {
-           lhsExprs.Add(new IdentifierExpr(lhs.Tok, lhs.Name) { RangeToken = new RangeToken(lhs.Tok, lhs.Tok) } );
+           lhsExprs.Add(new IdentifierExpr(lhs.Tok, lhs.Name) { RangeOrigin = new RangeToken(lhs.StartToken, lhs.StartToken) } );
          }
        } else { // not explicitly ghost, but with init - so auto-ghost
          foreach (var lhs in lhss) {
-           lhsExprs.Add(new AutoGhostIdentifierExpr(lhs.Tok, lhs.Name) { RangeToken = new RangeToken(lhs.Tok, lhs.Tok) } );
+           lhsExprs.Add(new AutoGhostIdentifierExpr(lhs.Origin, lhs.Name) { RangeOrigin = new RangeToken(lhs.StartToken, lhs.StartToken) } );
          }
        }
        var rangeToken = new RangeToken(startToken, t);
-       var updateRangeToken = new RangeToken(assignTok, t);
+       var updateRangeOrigin = new RangeToken(assignTok, t);
        if (suchThat != null) {
-         assignment = new AssignSuchThatStmt(updateRangeToken, lhsExprs, suchThat, suchThatAssume, attrs);
+         assignment = new AssignSuchThatStmt(updateRangeOrigin, lhsExprs, suchThat, suchThatAssume, attrs);
        } else if (exceptionRhs != null) {
-         assignment = new AssignOrReturnStmt(updateRangeToken, lhsExprs, exceptionRhs, keywordToken, rhss);
+         assignment = new AssignOrReturnStmt(updateRangeOrigin, lhsExprs, exceptionRhs, keywordToken, rhss);
        } else if (rhss.Count == 0) {
          assignment = null;
        } else {
-         assignment = new AssignStatement(updateRangeToken, lhsExprs, rhss);
+         assignment = new AssignStatement(updateRangeOrigin, lhsExprs, rhss);
        }
        s = new VarDeclStmt(rangeToken, lhss, assignment);
        if (proof != null) {
-         s = new BlockByProofStmt(s.RangeToken, proof, s);
+         s = new BlockByProofStmt(s.Origin, proof, s);
        }
     .)
   | (. CasePattern<LocalVariable> pat;
@@ -2579,8 +2577,8 @@ VarDeclStatement<.out Statement/*!*/ s.>
     Expression<out e, false, true>
 
     ";"
-    (. s = new VarDeclPattern(e.RangeToken, pat, e, isGhost);
-       s.RangeToken = new RangeToken(pat.StartToken, t); .)
+    (. s = new VarDeclPattern(e.Origin, pat, e, isGhost);
+       s.RangeOrigin = new RangeToken(pat.StartToken, t); .)
   )
   .
 
@@ -2730,7 +2728,7 @@ WhileStmt<out Statement stmt>
     | /* go body-less */
     )
     (.
-      var rangeToken = new RangeToken(startToken, t);
+      var rangeToken = new RangeToken(startToken, t, x);
       if (guardEllipsis != null || bodyEllipsis != null) {
         if (mod != null) {
           SemErr(ErrorId.p_no_modifies_on_refining_loops, mod[0].E.tok, "'modifies' clauses are not allowed on refining loops");
@@ -2845,18 +2843,18 @@ Guard<out Expression e>   /* null represents demonic-choice */
 BindingGuard<out Expression e, bool allowLambda>
 = (. var bvars = new List<BoundVar>();
      BoundVar bv;  
-     IOrigin x;
+     Token startToken;
      Attributes attrs = null;
      Expression body;
   .)
-  IdentTypeOptional<out bv>                    (. bvars.Add(bv); x = bv.tok; .)
+  IdentTypeOptional<out bv>                    (. bvars.Add(bv); startToken = bv.StartToken; .)
   { ","
     IdentTypeOptional<out bv>                  (. bvars.Add(bv); .)
   }
   { Attribute<ref attrs> }
   ":|"
   Expression<out body, true, allowLambda>
-  (. e = new ExistsExpr(x, new RangeToken(x, t), bvars, null, body, attrs); .)
+  (. e = new ExistsExpr(startToken, new RangeToken(startToken, t), bvars, null, body, attrs); .)
   .
 
 
@@ -2988,7 +2986,7 @@ AssertStmt<out Statement/*!*/ s>
      } else {
        s = new AssertStmt(new RangeToken(startToken, t), e, lbl == null ? null : new AssertLabel(lbl, lbl.val), attrs);
        if (proof != null) {
-         s = new BlockByProofStmt(s.RangeToken, proof, s);
+         s = new BlockByProofStmt(s.Origin, proof, s);
        }
      }
   .)
@@ -3201,8 +3199,7 @@ CalcStmt<out Statement s>
 
     /* now for the hint, which we build up as a possibly empty sequence of statements placed into one BlockStmt */
     (. var subhints = new List<Statement>();
-       Token hintStart = la;  
-       IOrigin hintEnd = hintStart.Prev;
+       Token hintStart = la;  Token hintEnd = hintStart.Prev;
        Token t0, t1;
        BlockStmt subBlock; Statement subCalc;
     .)
@@ -3292,7 +3289,7 @@ QSep = "::".
  * cardinality brackets, that is, "|expr|".
  */
 Expression<out Expression e, bool allowLemma, bool allowLambda, bool allowBitwiseOps = true, bool allowDecreasesTo = true>
-= (. Expression e0; Token semiToken; .)
+= (. Expression e0; Token semToken; .)
   [ "new" (. SemErr(ErrorId.p_no_side_effects_in_expressions, t, "Calls with side-effects such as constructors are not allowed in expressions."); .) ]
   EquivExpression<out e, allowLemma, allowLambda, allowBitwiseOps>
   [ IF(allowDecreasesTo && IsDecreasesTo())
@@ -3302,30 +3299,27 @@ Expression<out Expression e, bool allowLemma, bool allowLambda, bool allowBitwis
   ]
   [ IF(SemiFollowsCall(allowLemma, e))
     /* here we parse the ";E" that is part of a "LemmaCall;E" expression (other "S;E" expressions are parsed elsewhere) */
-    ";"                       (. semiToken = t; .)
+    ";"                       (. semToken = t; .)
     Expression<out e0, allowLemma, allowLambda>
     (. var startToken = e.StartToken;
-       e = new StmtExpr(e0.Tok,
-             new AssignStatement(e.RangeToken, new List<Expression>(), new List<AssignmentRhs>() { new ExprRhs(e) }),
+       e = new StmtExpr(semToken,
+             new AssignStatement(e.Origin, new List<Expression>(), new List<AssignmentRhs>() { new ExprRhs(e) }),
              e0);
-       e.RangeToken = new RangeToken(startToken, e0.EndToken);
+       e.RangeOrigin = new RangeToken(startToken, e0.EndToken);
     .)
   ]
   .
 
 /*------------------------------------------------------------------------*/
 EquivExpression<out Expression e0, bool allowLemma, bool allowLambda, bool allowBitwiseOps>
-= (. Contract.Ensures(Contract.ValueAtReturn(out e0) != null); 
-     Token/*!*/ x;  
-     Expression/*!*/ e1; 
-  .)
+= (. Contract.Ensures(Contract.ValueAtReturn(out e0) != null); Token/*!*/ x;  Expression/*!*/ e1; .)
   ImpliesExpliesExpression<out e0, allowLemma, allowLambda, allowBitwiseOps>
   { IF(IsEquivOp())  /* read an EquivExpression as far as possible */
     EquivOp                                                   (. x = t; .)
     ImpliesExpliesExpression<out e1, allowLemma, allowLambda, allowBitwiseOps>  (.
       var startToken = e0.StartToken;
       e0 = new BinaryExpr(x, BinaryExpr.Opcode.Iff, e0, e1);
-      e0.RangeToken = new RangeToken(startToken, t); .)
+      e0.RangeOrigin = new RangeToken(startToken, t); .)
   }
   .
 
@@ -3342,18 +3336,18 @@ ImpliesExpliesExpression<out Expression e0, bool allowLemma, bool allowLambda, b
     ( ImpliesOp                                               (. x = t; .)
       ImpliesExpression<out e1, allowLemma, allowLambda, allowBitwiseOps>       (. var startToken = e0.StartToken;
                                                                                    e0 = new BinaryExpr(x, BinaryExpr.Opcode.Imp, e0, e1);
-                                                                                   e0.RangeToken = new RangeToken(startToken, t); .)
+                                                                                   e0.RangeOrigin = new RangeToken(startToken, t); .)
     | ExpliesOp                                               (. x = t; .)
       LogicalExpression<out e1, allowLemma, allowLambda, allowBitwiseOps>       (. // The order of operands is reversed so that it can be turned into implication during resolution
                                                                  var startToken = e0.StartToken;
                                                                  e0 = new BinaryExpr(x, BinaryExpr.Opcode.Exp, e1, e0);
-                                                                 e0.RangeToken = new RangeToken(startToken, t); .)
+                                                                 e0.RangeOrigin = new RangeToken(startToken, t); .)
       { IF(IsExpliesOp())  /* read a reverse implication as far as possible */
         ExpliesOp                                             (. x = t; .)
         LogicalExpression<out e1, allowLemma, allowLambda, allowBitwiseOps>     (. //The order of operands is reversed so that it can be turned into implication during resolution
                                                                  startToken = e0.StartToken;
                                                                  e0 = new BinaryExpr(x, BinaryExpr.Opcode.Exp, e1, e0);
-                                                                 e0.RangeToken = new RangeToken(startToken, t);
+                                                                 e0.RangeOrigin = new RangeToken(startToken, t);
                                                               .)
       }
       [ IF(IsImpliesOp()) ImpliesOp (. SemErr(ErrorId.p_ambiguous_implies, t, "Ambiguous use of ==> and <==. Use parentheses to disambiguate."); .) 
@@ -3372,7 +3366,7 @@ ImpliesExpression<out Expression e0, bool allowLemma, bool allowLambda, bool all
     (. x = t; .)
     ImpliesExpression<out e1, allowLemma, allowLambda, allowBitwiseOps>       (. var startToken = e0.StartToken;
                                                                                  e0 = new BinaryExpr(x, BinaryExpr.Opcode.Imp, e0, e1); 
-                                                                                 e0.RangeToken = new RangeToken(startToken, t);.)
+                                                                                 e0.RangeOrigin = new RangeToken(startToken, t);.)
   ]
   .
 
@@ -3380,7 +3374,7 @@ ImpliesExpression<out Expression e0, bool allowLemma, bool allowLambda, bool all
 LogicalExpression<out Expression e0, bool allowLemma, bool allowLambda, bool allowBitwiseOps>
 = (. Contract.Ensures(Contract.ValueAtReturn(out e0) != null); Token/*!*/ x = null;  Expression/*!*/ e1;
      Expression first;
-     IOrigin startToken = null;
+     Token startToken = null;
      Token/*!*/ firstOp = null;
      Token/*!*/ prefixOp = null;
      e0 = dummyExpr; /* mute the warning */
@@ -3397,7 +3391,7 @@ LogicalExpression<out Expression e0, bool allowLemma, bool allowLambda, bool all
     RelationalExpression<out e1, allowLemma, allowLambda, allowBitwiseOps>
          (. startToken = e0.StartToken;
             e0 = new BinaryExpr(x, firstOp.val == "&&" ? BinaryExpr.Opcode.And : BinaryExpr.Opcode.Or, e0, e1);
-            e0.RangeToken = new RangeToken(startToken, t);
+            e0.RangeOrigin = new RangeToken(startToken, t);
          .)
   }
   (.
@@ -3406,10 +3400,10 @@ LogicalExpression<out Expression e0, bool allowLemma, bool allowLambda, bool all
          // be a boolean, we conjoin "true" of "false" to its left.
          if (firstOp.val == "&&") e0 = new BinaryExpr(x, BinaryExpr.Opcode.And, new LiteralExpr(new AutoGeneratedOrigin(x), true), e0);
          else e0 = new BinaryExpr(x, BinaryExpr.Opcode.Or, new LiteralExpr(new AutoGeneratedOrigin(x), false), e0);
-         e0.RangeToken = new RangeToken(firstOp, t);
+         e0.RangeOrigin = new RangeToken(firstOp, t);
          e0.FormatTokens = new[] { firstOp };
        } else if(prefixOp != null) {
-         e0.RangeToken = new RangeToken(prefixOp, e0.EndToken);
+         e0.RangeOrigin = new RangeToken(prefixOp, e0.EndToken);
        }
   .)
   .
@@ -3422,7 +3416,7 @@ RelationalExpression<out Expression e, bool allowLemma, bool allowLambda, bool a
      List<BinaryExpr.Opcode> ops = null;
      List<IOrigin> opLocs = null;
      List<Expression/*?*/> prefixLimits = null;
-     IOrigin startToken = null;
+     Token startToken = null;
      Expression k;
      int kind = 0;  // 0 ("uncommitted") indicates chain of ==, possibly with one !=
                     // 1 ("ascending")   indicates chain of ==, <, <=, possibly with one !=
@@ -3443,7 +3437,7 @@ RelationalExpression<out Expression e, bool allowLemma, bool allowLambda, bool a
                                         Contract.Assert(op == BinaryExpr.Opcode.Eq || op == BinaryExpr.Opcode.Neq);
                                         e = new TernaryExpr(x, op == BinaryExpr.Opcode.Eq ? TernaryExpr.Opcode.PrefixEqOp : TernaryExpr.Opcode.PrefixNeqOp, k, e0, e1);
                                       }
-                                      e.RangeToken = new RangeToken(startToken, t);
+                                      e.RangeOrigin = new RangeToken(startToken, t);
                                    .)
     { IF(IsRelOp())  /* read a RelationalExpression as far as possible */
                                    (. if (chain == null) {
@@ -3504,7 +3498,7 @@ RelationalExpression<out Expression e, bool allowLemma, bool allowLambda, bool a
   (. if (chain != null && kind != 3) {
        e = new ChainingExpression(opLocs[0], chain, ops, opLocs, prefixLimits);
      }
-     e.RangeToken = new RangeToken(startToken, t);
+     e.RangeOrigin = new RangeToken(startToken, t);
   .)
   .
 
@@ -3568,7 +3562,7 @@ ShiftTerm<out Expression e0, bool allowLemma, bool allowLambda, bool allowBitwis
     Term<out e1, allowLemma, allowLambda, allowBitwiseOps> (.
       var startToken = e0.StartToken;
       e0 = new BinaryExpr(x, op, e0, e1);
-      e0.RangeToken = new RangeToken(startToken, t);
+      e0.RangeOrigin = new RangeToken(startToken, t);
      .)
   }
   .
@@ -3582,7 +3576,7 @@ Term<out Expression e0, bool allowLemma, bool allowLambda, bool allowBitwiseOps>
     Factor<out e1, allowLemma, allowLambda, allowBitwiseOps>
     (. var startToken = e0.StartToken;
        e0 = new BinaryExpr(x, op, e0, e1);
-       e0.RangeToken = new RangeToken(startToken, t); .)
+       e0.RangeOrigin = new RangeToken(startToken, t); .)
   }
   .
 
@@ -3604,7 +3598,7 @@ Factor<out Expression e0, bool allowLemma, bool allowLambda, bool allowBitwiseOp
     (. 
       var startToken = e0.StartToken;
       e0 = new BinaryExpr(x, op, e0, e1);
-      e0.RangeToken = new RangeToken(startToken, t);
+      e0.RangeOrigin = new RangeToken(startToken, t);
     .)
   }
   .
@@ -3627,11 +3621,11 @@ BitvectorFactor<out Expression e0, bool allowLemma, bool allowLambda, bool allow
     | "|"                                                (. op = BinaryExpr.Opcode.BitwiseOr; x = t; .)
     | "^"                                                (. op = BinaryExpr.Opcode.BitwiseXor; x = t; .)
     )
-    AsExpression<out e1, allowLemma, allowLambda, allowBitwiseOps>   (. var startToken = e0.StartToken; e0 = new BinaryExpr(x, op, e0, e1); e0.RangeToken = new RangeToken(startToken, t); .)
+    AsExpression<out e1, allowLemma, allowLambda, allowBitwiseOps>   (. var startToken = e0.StartToken; e0 = new BinaryExpr(x, op, e0, e1); e0.RangeOrigin = new RangeToken(startToken, t); .)
     { IF(IsBitwiseOp())
       ( "&" | "|" | "^" )                                (. if (x.kind != t.kind && !ambig) { ambig = true; SemErr(ErrorId.p_ambiguous_bitop, t, "Ambiguous use of &, |, ^. Use parentheses to disambiguate."); }
                                                             x = t; .)
-      AsExpression<out e1, allowLemma, allowLambda, allowBitwiseOps> (. startToken = e0.StartToken; e0 = new BinaryExpr(x, op, e0, e1); e0.RangeToken = new RangeToken(startToken, t); .)
+      AsExpression<out e1, allowLemma, allowLambda, allowBitwiseOps> (. startToken = e0.StartToken; e0 = new BinaryExpr(x, op, e0, e1); e0.RangeOrigin = new RangeToken(startToken, t); .)
     }
   ]
   .
@@ -3642,9 +3636,9 @@ AsExpression<out Expression e, bool allowLemma, bool allowLambda, bool allowBitw
   UnaryExpression<out e, allowLemma, allowLambda, allowBitwiseOps>
   { IF(IsAsOrIs())
     ( "as"                                  (. tok = t; .)
-      TypeAndToken<out x, out toType, true> (. e = new ConversionExpr(tok, e, toType) { RangeToken = new RangeToken(e.StartToken, t)}; .)
+      TypeAndToken<out x, out toType, true> (. e = new ConversionExpr(tok, e, toType) { RangeOrigin = new RangeToken(e.StartToken, t)}; .)
     | "is"                                  (. tok = t; .)
-      TypeAndToken<out x, out toType, true> (. e = new TypeTestExpr(tok, e, toType) { RangeToken = new RangeToken(e.StartToken, t)}; .)
+      TypeAndToken<out x, out toType, true> (. e = new TypeTestExpr(tok, e, toType) { RangeOrigin = new RangeToken(e.StartToken, t)}; .)
     )
   }
   .
@@ -3653,9 +3647,9 @@ AsExpression<out Expression e, bool allowLemma, bool allowLambda, bool allowBitw
 UnaryExpression<out Expression e, bool allowLemma, bool allowLambda, bool allowBitwiseOps>
 = (. Contract.Ensures(Contract.ValueAtReturn(out e) != null); Token/*!*/ x;  e = dummyExpr; .)
   ( "-"                                             (. x = t; .)
-    UnaryExpression<out e, allowLemma, allowLambda, allowBitwiseOps>  (. e = new NegationExpression(x, e) { RangeToken = new RangeToken(x, t) }; .)
+    UnaryExpression<out e, allowLemma, allowLambda, allowBitwiseOps>  (. e = new NegationExpression(x, e) { RangeOrigin = new RangeToken(x, t) }; .)
   | NegOp                                           (. x = t; .)
-    UnaryExpression<out e, allowLemma, allowLambda, allowBitwiseOps>  (. e = new UnaryOpExpr(x, UnaryOpExpr.Opcode.Not, e) { RangeToken = new RangeToken(x, t) }; .)
+    UnaryExpression<out e, allowLemma, allowLambda, allowBitwiseOps>  (. e = new UnaryOpExpr(x, UnaryOpExpr.Opcode.Not, e) { RangeOrigin = new RangeToken(x, t) }; .)
   | PrimaryExpression<out e, allowLemma, allowLambda, allowBitwiseOps>
   )
   .
@@ -3723,7 +3717,7 @@ ConstAtomExpression<out Expression e>
   | "assigned"                                 (. x = t; .)
     "(" NameSegment<out e> ")"                 (. e = new UnaryOpExpr(x, UnaryOpExpr.Opcode.Assigned, e); .)
   | ParensExpression<out e>
-  ) (. if(x!= null) { e.RangeToken = new RangeToken(x, t); } .)
+  ) (. if(x!= null) { e.RangeOrigin = new RangeToken(x, t); } .)
   .
 
 /*------------------------------------------------------------------------*/
@@ -3747,7 +3741,7 @@ LiteralExpression<out Expression e>
                                                   Util.ValidateEscaping(theOptions, t, s, isVerbatimString, errors);
                                                   e = new StringLiteralExpr(t, s, isVerbatimString);
                                                .)
-  ) (. e.RangeToken = new RangeToken(t, t); .)
+  ) (. e.RangeOrigin = new RangeToken((Token)t, (Token)t); .)
   .
 
 /*------------------------------------------------------------------------*/
@@ -3773,7 +3767,7 @@ LambdaExpression<out Expression e, bool allowLemma, bool allowBitwiseOps>
      Expression req = null;
      Expression body = null;
   .)
-  ( WildIdent<out id, true>                  (. x = t; bvs.Add(new BoundVar(id, id.val, new InferredTypeProxy()) {RangeToken = new RangeToken(x, x)}); .)
+  ( WildIdent<out id, true>                  (. x = t; bvs.Add(new BoundVar(id, id.val, new InferredTypeProxy()) {RangeOrigin = new RangeToken(x, x)}); .)
   | "("                                      (. x = t; .)
       [
         IdentTypeOptional<out bv>            (. bvs.Add(bv); .)
@@ -3794,7 +3788,7 @@ LambdaExpression<out Expression e, bool allowLemma, bool allowBitwiseOps>
 LambdaSpec<.ref List<FrameExpression> reads, ref Attributes readsAttrs, ref Expression req.>
 = { ReadsClause<reads, ref readsAttrs, true, false, true>
   | "requires"                             (. Expression ee; .)
-    Expression<out ee, true, false>        (. req = req == null ? ee : new BinaryExpr(req.tok, BinaryExpr.Opcode.And, req, ee) { RangeToken = new RangeToken(req.StartToken, ee.EndToken) } ; .)
+    Expression<out ee, true, false>        (. req = req == null ? ee : new BinaryExpr(req.tok, BinaryExpr.Opcode.And, req, ee) { RangeOrigin = new RangeToken(req.StartToken, ee.EndToken) } ; .)
   }
   .
 
@@ -3846,7 +3840,7 @@ ParensExpression<out Expression e>
          e = new ParensExpression(lp, e);
        }
      }
-     e.RangeToken = new RangeToken(lp, rp);
+     e.RangeOrigin = new RangeToken(lp, rp);
   .)
   .
 
@@ -3922,7 +3916,7 @@ SetDisplayExpr<out Expression e>
                                                .)
     ")"
   )
-  (. e.RangeToken = new RangeToken(startToken, t); .)
+  (. e.RangeOrigin = new RangeToken(startToken, t); .)
   .
 
 /*------------------------------------------------------------------------*/
@@ -3958,7 +3952,7 @@ SeqDisplayExpr<out Expression e>
                                              .)
     "]"
   )
-  (.  e.RangeToken = new RangeToken(x, t); .)
+  (.  e.RangeOrigin = new RangeToken(x, t); .)
   .
 
 /*------------------------------------------------------------------------*/
@@ -3971,7 +3965,7 @@ MapDisplayExpr<out Expression e>
   "["
     [ MapLiteralExpressions<out elements> ] 
                      (. e = new MapDisplayExpr(mapToken, mapToken.kind == _map, elements);.)
-  "]"                (. e.RangeToken = new RangeToken(mapToken, t); .)
+  "]"                (. e.RangeOrigin = new RangeToken(mapToken, t); .)
   .
 
 /*------------------------------------------------------------------------*/
@@ -4021,7 +4015,7 @@ EndlessExpression<out Expression e, bool allowLemma, bool allowLambda, bool allo
   | SetComprehensionExpr<out e, allowLemma, allowLambda, allowBitwiseOps>
   | StmtInExpr<out s>
     Expression<out e, allowLemma, allowLambda, allowBitwiseOps>
-    (. e = new StmtExpr(s.Tok, s, e) { RangeToken = new RangeToken(s.StartToken, e.EndToken) }; .)
+    (. e = new StmtExpr(s.EndToken, s, e) { RangeOrigin = new RangeToken(s.StartToken, e.EndToken) }; .)
   | LetExpression<out e, allowLemma, allowLambda, allowBitwiseOps>
   | MapComprehensionExpr<out e, allowLemma, allowLambda, allowBitwiseOps>
   )
@@ -4046,10 +4040,10 @@ IfExpression<out Expression e, bool allowLemma, bool allowLambda, bool allowBitw
                        LHSs.Add(new CasePattern<BoundVar>(e.tok, v));
                      }
                      e0 = new LetExpr(e.tok, LHSs, new List<Expression>() {
-                       exists.Term }, e0, false) { RangeToken = exists.RangeToken};
+                       exists.Term }, e0, false) { RangeOrigin =exists.Origin};
                  }
                  e = new ITEExpr(x, isBindingGuard, e, e0, e1);
-                 e.RangeToken = new RangeToken(x, t);
+                 e.RangeOrigin = new RangeToken(x, t);
                 .)
   .
 /*------------------------------------------------------------------------*/
@@ -4134,7 +4128,7 @@ LetExprWithLHS<out Expression e, bool allowLemma, bool allowLambda, bool allowBi
     } else {
       e = new LetExpr(x, letLHSs, letRHSs, e, exact, attrs);
     }
-    e.RangeToken = new RangeToken(x, t);
+    e.RangeOrigin = new RangeToken(x, t);
   .)
   .
 
@@ -4149,7 +4143,7 @@ LetExprWithoutLHS<out Expression e, bool allowLemma, bool allowLambda, bool allo
   ";"
   Expression<out body, allowLemma, allowLambda, allowBitwiseOps>
   (. e = new LetOrFailExpr(x, null, rhs, body);
-     e.RangeToken = new RangeToken(x, t);
+     e.RangeOrigin = new RangeToken(x, t);
    .)
   .
 
@@ -4170,7 +4164,7 @@ MatchExpression<out Expression e, bool allowLemma, bool allowLambda, bool allowB
         }
   )
   (. e = new NestedMatchExpr(x, e, cases, usesOptionalBraces);
-     e.RangeToken = new RangeToken(x, t); .)
+     e.RangeOrigin = new RangeToken(x, t); .)
 .
 
 /*------------------------------------------------------------------------*/
@@ -4294,7 +4288,7 @@ NameSegment<out Expression e>
      } else {
        Contract.Assert(atLabel == null);
      }
-     e.RangeToken = new RangeToken(id, t);
+     e.RangeOrigin = new RangeToken(id, t);
   .)
   .
 
@@ -4305,7 +4299,7 @@ NameSegmentForTypeName<out Expression e, bool inExpressionContext>
   Ident<out id>
   OptGenericInstantiation<out typeArgs, inExpressionContext>
   (. e = new NameSegment(id, id.val, typeArgs);
-     e.RangeToken = new RangeToken(id, t);
+     e.RangeOrigin = new RangeToken(id, t);
   .)
   .
 
@@ -4360,10 +4354,10 @@ Suffix<ref Expression e>
         { "," MemberBindingUpdate<out id, out v>      (. updates.Add(Tuple.Create((IOrigin)id, id.val, v)); .)
         }
       ")"
-      (. e = new DatatypeUpdateExpr(x, e, updates) { RangeToken = new RangeToken(startToken, t)}; .)
+      (. e = new DatatypeUpdateExpr(x, e, updates) { RangeOrigin = new RangeToken(startToken, t)}; .)
     | DotSuffix<out id, out x>                 (. if (x != null) {
                                                     // process id as a Suffix in its own right
-                                                    e = new ExprDotName(id, e, id.val, null) { RangeToken = new RangeToken(startToken, t)};
+                                                    e = new ExprDotName(id, e, id.val, null) { RangeOrigin = new RangeToken(startToken, t)};
                                                     id = x;  // move to the next Suffix
                                                   }
                                                   Token openParen = null;  List<Type> typeArgs = null;
@@ -4381,12 +4375,10 @@ Suffix<ref Expression e>
           AtCall<out atLabel, out openParen, out args> ]
       )
       (. e = new ExprDotName(id, e, id.val, typeArgs) {
-           RangeToken = new RangeToken(startToken, id)
+           RangeOrigin = new RangeToken(startToken, id)
          };
          if (openParen != null) {
-           e = new ApplySuffix(openParen, atLabel, e, args, t) {
-             RangeToken = new RangeToken(startToken, t)
-           };
+           e = new ApplySuffix(new RangeToken(startToken, t, openParen), atLabel, e, args, t);
          } else {
            Contract.Assert(atLabel == null);
          }
@@ -4442,16 +4434,16 @@ Suffix<ref Expression e>
              List<Expression> seqs = new List<Expression>();
               foreach (var len in multipleLengths) {
                 var end = prev == null ? len : new BinaryExpr(x, BinaryExpr.Opcode.Add, prev, len) {
-                  RangeToken = new RangeToken(prev.StartToken, len.EndToken)
+                  RangeOrigin = new RangeToken(prev.StartToken, len.EndToken)
                 };
                 seqs.Add(new SeqSelectExpr(x, false, e, prev, end, t) {
-                  RangeToken = new RangeToken(e.StartToken, t)
+                  RangeOrigin = new RangeToken(e.StartToken, t)
                 });
                 prev = end;
               }
              if (takeRest) {
                seqs.Add(new SeqSelectExpr(x, false, e, prev, null, t) {
-                 RangeToken = new RangeToken(e.StartToken, t)
+                 RangeOrigin = new RangeToken(e.StartToken, t)
                });
              }
              e = new SeqDisplayExpr(x, seqs);
@@ -4463,12 +4455,11 @@ Suffix<ref Expression e>
              e = new SeqUpdateExpr(x, e, e0, e1);
            }
          }
-         e.RangeToken = new RangeToken(startToken, t);
+         e.RangeOrigin = new RangeToken(startToken, t);
       .)
   | "("                                    (. Token openParen = t; var args = new List<ActualBinding>(); .)
     [ ActualBindings<args> ]
-    ")"                                    (. e = new ApplySuffix(openParen, null, e, args, t);
-                                              e.RangeToken = new RangeToken(startToken, t);
+    ")"                                    (. e = new ApplySuffix(new RangeToken(startToken, t, openParen), null, e, args, t);
                                            .)
   )
   .
@@ -4510,7 +4501,7 @@ QuantifierExpression<out Expression q, bool allowLemma, bool allowLambda>
     ForallStatementEnsuresAndBody<out var forallStatement, x, bvars, attrs, range>
     Expression<out var expr, allowLemma, allowLambda>
     (. q = new StmtExpr(forallStatement.Tok, forallStatement, expr) {
-         RangeToken = new RangeToken(forallStatement.StartToken, forallStatement.EndToken)
+         RangeOrigin = new RangeToken(forallStatement.StartToken, forallStatement.EndToken)
        };
     .)
 
@@ -4627,7 +4618,7 @@ Attribute<ref Attributes attrs>
      var rtok = new RangeToken(openBrace, t);
      if (!CheckAttribute(errors, x, rtok)) return;
      attrs = new UserSuppliedAttributes(x, openBrace, closeBrace, args, attrs);
-     attrs.RangeToken = rtok;
+     attrs.RangeOrigin =rtok;
   .)
   .
 
@@ -4649,7 +4640,7 @@ AtAttribute<ref Attributes attrs>
   (. 
      var rtok = new RangeToken(atToken, t);
      attrs = new UserSuppliedAtAttribute(t, arg, attrs);
-     attrs.RangeToken = rtok;
+     attrs.RangeOrigin =rtok;
   .)
   .
 
@@ -4810,7 +4801,7 @@ WildIdentN<out Name name, bool allowWildcardId>
 // Identifier, disallowing leading underscores, except possibly the "wildcard" identifier "_"
 WildIdent<out Token x, bool allowWildcardId>
 = (. Contract.Ensures(Contract.ValueAtReturn(out x) != null); .)
-  Ident<out x>     (. x = (Token)t.WithVal(UnwildIdent(t, allowWildcardId)); .)
+  Ident<out x>     (. x = t.WithVal(UnwildIdent(t, allowWildcardId)); .)
   .
 
 /*------------------------------------------------------------------------*/
@@ -4864,4 +4855,4 @@ Dec<out BaseTypes.BigDec d>
   .
 
 /*------------------------------------------------------------------------*/
-END Dafny.
\ No newline at end of file
+END Dafny.
diff --git a/Source/DafnyCore/Generic/ConsoleErrorReporter.cs b/Source/DafnyCore/Generic/ConsoleErrorReporter.cs
index 4c9048b8666..5b84329569b 100644
--- a/Source/DafnyCore/Generic/ConsoleErrorReporter.cs
+++ b/Source/DafnyCore/Generic/ConsoleErrorReporter.cs
@@ -45,7 +45,7 @@ protected override bool MessageCore(MessageSource source, ErrorLevel level, stri
 
     if (Options.Get(Snippets.ShowSnippets) && tok.Uri != null) {
       var tw = new StringWriter();
-      Snippets.WriteSourceCodeSnippet(Options, tok.ToRange(), tw);
+      Snippets.WriteSourceCodeSnippet(Options, tok, tw);
       errorLine += tw.ToString();
     }
 
@@ -68,7 +68,7 @@ protected override bool MessageCore(MessageSource source, ErrorLevel level, stri
       errorLine += $"{innerToken.TokenToString(Options)}: {innerMessage}\n";
       if (Options.Get(Snippets.ShowSnippets) && tok.Uri != null) {
         var tw = new StringWriter();
-        Snippets.WriteSourceCodeSnippet(Options, innerToken.ToRange(), tw);
+        Snippets.WriteSourceCodeSnippet(Options, innerToken, tw);
         errorLine += tw.ToString();
       }
     }
diff --git a/Source/DafnyCore/Generic/EmptyNode.cs b/Source/DafnyCore/Generic/EmptyNode.cs
index f443e455d40..a54d3083f57 100644
--- a/Source/DafnyCore/Generic/EmptyNode.cs
+++ b/Source/DafnyCore/Generic/EmptyNode.cs
@@ -4,7 +4,12 @@
 namespace Microsoft.Dafny;
 
 public class EmptyNode : Node {
-  public override RangeToken RangeToken { get; set; } = new(new Token(), new Token());
+  public override IOrigin Origin { get; } = new RangeToken(new Token(), new Token());
+
+  public override IOrigin RangeOrigin {
+    set => throw new System.NotImplementedException();
+  }
+
   public override IOrigin Tok => new Token();
   public override IEnumerable<INode> Children => Enumerable.Empty<Node>();
   public override IEnumerable<INode> PreResolveChildren => Enumerable.Empty<Node>();
diff --git a/Source/DafnyCore/Generic/ErrorRegistry.cs b/Source/DafnyCore/Generic/ErrorRegistry.cs
index 3b09fccfdd2..5b77ea1877c 100644
--- a/Source/DafnyCore/Generic/ErrorRegistry.cs
+++ b/Source/DafnyCore/Generic/ErrorRegistry.cs
@@ -29,8 +29,8 @@ public bool Contains(DafnyPosition position) {
 /// <param name="Range">The range to replace. The start is given by the token's start, and the length is given by the val's length.</param>
 /// <param name="Replacement"></param>
 public record DafnyCodeActionEdit(DafnyRange Range, string Replacement = "") {
-  public DafnyCodeActionEdit(RangeToken rangeOrigin, string replacement = "", bool includeTrailingWhitespace = false)
-    : this(rangeOrigin.ToDafnyRange(includeTrailingWhitespace), replacement) {
+  public DafnyCodeActionEdit(RangeToken rangeToken, string replacement = "", bool includeTrailingWhitespace = false)
+    : this(rangeToken.ToDafnyRange(includeTrailingWhitespace), replacement) {
   }
 }
 
@@ -86,7 +86,7 @@ public static RangeToken IncludeComma(RangeToken range) {
 
   public static RangeToken ExpandStart(RangeToken range, TokenPredicate pred, bool include) {
     var t = range.StartToken;
-    IOrigin p = null;
+    Token p = null;
     while (!pred(t)) {
       p = t;
       t = t.Prev;
@@ -99,7 +99,7 @@ public static RangeToken ExpandStart(RangeToken range, TokenPredicate pred, bool
 
   public static RangeToken ExpandEnd(RangeToken range, TokenPredicate pred, bool include) {
     var t = range.EndToken;
-    IOrigin p = null;
+    Token p = null;
     while (!pred(t)) {
       p = t;
       t = t.Prev;
diff --git a/Source/DafnyCore/Generic/ErrorReporter.cs b/Source/DafnyCore/Generic/ErrorReporter.cs
index 660dfddc5ae..a939c073f1a 100644
--- a/Source/DafnyCore/Generic/ErrorReporter.cs
+++ b/Source/DafnyCore/Generic/ErrorReporter.cs
@@ -104,14 +104,14 @@ public void Error(MessageSource source, Statement s, string format, params objec
     Contract.Requires(s != null);
     Contract.Requires(format != null);
     Contract.Requires(args != null);
-    Error(source, ParseErrors.ErrorId.none, s.Tok, format, args);
+    Error(source, ParseErrors.ErrorId.none, s.Origin, format, args);
   }
 
   public void Error(MessageSource source, INode v, string format, params object[] args) {
     Contract.Requires(v != null);
     Contract.Requires(format != null);
     Contract.Requires(args != null);
-    Error(source, ParseErrors.ErrorId.none, v.Tok, format, args);
+    Error(source, ParseErrors.ErrorId.none, v.Origin, format, args);
   }
 
   public void Error(MessageSource source, Enum errorId, INode v, string format, params object[] args) {
diff --git a/Source/DafnyCore/Generic/INode.cs b/Source/DafnyCore/Generic/INode.cs
new file mode 100644
index 00000000000..03965a140da
--- /dev/null
+++ b/Source/DafnyCore/Generic/INode.cs
@@ -0,0 +1,17 @@
+using System.Collections.Generic;
+
+namespace Microsoft.Dafny;
+
+public interface INode {
+  bool SingleFileToken { get; }
+
+  public Token Center => Origin.Center; // TODO inline
+  public Token StartToken => Origin.StartToken; // TODO inline
+  public Token EndToken => Origin.EndToken; // TODO inline
+  IEnumerable<IOrigin> OwnedTokens { get; }
+  IOrigin Origin { get; }
+  IOrigin RangeOrigin { set; } // TODO remove
+  IOrigin Tok { get; } // TODO remove
+  IEnumerable<INode> Children { get; }
+  IEnumerable<INode> PreResolveChildren { get; }
+}
\ No newline at end of file
diff --git a/Source/DafnyCore/Generic/Name.cs b/Source/DafnyCore/Generic/Name.cs
index 9cf9af42421..a6ba202a116 100644
--- a/Source/DafnyCore/Generic/Name.cs
+++ b/Source/DafnyCore/Generic/Name.cs
@@ -12,15 +12,15 @@ namespace Microsoft.Dafny;
 public class Name : RangeNode {
 
   public Name Prepend(string prefix) {
-    return new Name(RangeToken.MakeAutoGenerated(), prefix + Value);
+    return new Name(Origin.MakeAutoGenerated(), prefix + Value);
   }
 
   public Name Append(string suffix) {
-    return new Name(RangeToken, Value + suffix);
+    return new Name(Origin, Value + suffix);
   }
 
   public Name Update(Func<string, string> update) {
-    return new Name(RangeToken, update(Value));
+    return new Name(Origin, update(Value));
   }
   public string Value { get; set; }
 
@@ -28,14 +28,14 @@ public Name(Cloner cloner, Name original) : base(cloner, original) {
     Value = original.Value;
   }
 
-  public Name(RangeToken range, string value) : base(range) {
+  public Name(IOrigin range, string value) : base(range) {
     this.Value = value;
   }
 
-  public Name(IOrigin token) : this(new RangeToken(token, token), token.val) {
+  public Name(Token token) : this(new RangeToken(token, token), token.val) {
   }
 
-  public Name(string value) : base(RangeToken.NoToken) {
+  public Name(string value) : base(Microsoft.Dafny.RangeToken.NoToken) {
     this.Value = value;
   }
 
@@ -43,7 +43,7 @@ public Name(string value) : base(RangeToken.NoToken) {
   public override IEnumerable<INode> PreResolveChildren => Children;
 
   public Name Clone(Cloner cloner) {
-    return new Name(cloner.Tok(RangeToken), Value);
+    return new Name(cloner.Origin(Origin), Value);
   }
 
   public override string ToString() => Value;
diff --git a/Source/DafnyCore/Generic/Node.cs b/Source/DafnyCore/Generic/Node.cs
index c292997423e..29ffa0e84d4 100644
--- a/Source/DafnyCore/Generic/Node.cs
+++ b/Source/DafnyCore/Generic/Node.cs
@@ -1,26 +1,14 @@
 using System;
 using System.Collections.Generic;
-using System.Diagnostics;
 using System.Diagnostics.Contracts;
 using System.Linq;
 using System.Text.RegularExpressions;
-using Microsoft.Boogie;
+using Dafny;
 using Microsoft.Dafny.Auditor;
 using Action = System.Action;
 
 namespace Microsoft.Dafny;
 
-public interface INode {
-  bool SingleFileToken { get; }
-  public IOrigin StartToken => RangeToken.StartToken;
-  public IOrigin EndToken => RangeToken.EndToken;
-  IEnumerable<IOrigin> OwnedTokens { get; }
-  RangeToken RangeToken { get; }
-  IOrigin Tok { get; }
-  IEnumerable<INode> Children { get; }
-  IEnumerable<INode> PreResolveChildren { get; }
-}
-
 public interface ICanFormat : INode {
   /// Sets the indentation of individual tokens owned by this node, given
   /// the new indentation set by the tokens preceding this node
@@ -36,9 +24,10 @@ public abstract class Node : INode {
   protected IReadOnlyList<IOrigin> OwnedTokensCache;
 
   public virtual bool SingleFileToken => true;
-  public IOrigin StartToken => RangeToken?.StartToken;
+  public Token Center => Tok.Center;
+  public Token StartToken => Origin?.StartToken;
 
-  public IOrigin EndToken => RangeToken?.EndToken;
+  public Token EndToken => Origin?.EndToken;
   public abstract IOrigin Tok { get; }
 
   /// <summary>
@@ -56,7 +45,7 @@ public abstract class Node : INode {
   /// </summary>
   public abstract IEnumerable<INode> PreResolveChildren { get; }
 
-  public IEnumerable<IOrigin> CoveredTokens {
+  public IEnumerable<Token> CoveredTokens {
     get {
       var token = StartToken;
       if (token == Token.NoToken) {
@@ -114,6 +103,8 @@ public IEnumerable<IOrigin> OwnedTokens {
     }
   }
 
+  public abstract IOrigin Origin { get; }
+
   /// <summary>
   // Nodes like DefaultClassDecl have children but no OwnedTokens as they are not "physical"
   // Therefore, we have to find all the concrete children by unwrapping such nodes. 
@@ -130,7 +121,7 @@ private static IEnumerable<INode> GetConcreteChildren(INode node) {
     }
   }
 
-  public abstract RangeToken RangeToken { get; set; }
+  public abstract IOrigin RangeOrigin { set; }
 
   // <summary>
   // Returns all assumptions contained in this node or its descendants.
@@ -142,7 +133,7 @@ public virtual IEnumerable<Assumption> Assumptions(Declaration decl) {
     return Enumerable.Empty<Assumption>();
   }
 
-  public ISet<INode> Visit(Func<INode, bool> beforeChildren = null, Action<INode> afterChildren = null, Action<Exception> reportError = null) {
+  public System.Collections.Generic.ISet<INode> Visit(Func<INode, bool> beforeChildren = null, Action<INode> afterChildren = null, Action<Exception> reportError = null) {
     reportError ??= _ => { };
     beforeChildren ??= node => true;
 
@@ -202,89 +193,4 @@ protected bool GetStartTriviaDocstring(out string trivia) {
     }
     return trivia is not ("" or null);
   }
-}
-
-public abstract class TokenNode : Node {
-  // Contains tokens that did not make it in the AST but are part of the expression,
-  // Enables ranges to be correct.
-  // TODO: Re-add format tokens where needed until we put all the formatting to replace the tok of every expression
-  internal IOrigin[] FormatTokens = null;
-
-  protected RangeToken RangeOrigin = null;
-
-  public IOrigin tok = Token.NoToken;
-
-  [DebuggerBrowsable(DebuggerBrowsableState.Never)]
-  public override IOrigin Tok {
-    get => tok;
-  }
-
-  public override RangeToken RangeToken {
-    get {
-      if (RangeOrigin == null) {
-
-        var startTok = tok;
-        var endTok = tok;
-
-        void UpdateStartEndToken(IOrigin token1) {
-          if (token1.Filepath != tok.Filepath) {
-            return;
-          }
-
-          if (token1.pos < startTok.pos) {
-            startTok = token1;
-          }
-
-          if (token1.pos + token1.val.Length > endTok.pos + endTok.val.Length) {
-            endTok = token1;
-          }
-        }
-
-        void UpdateStartEndTokRecursive(INode node) {
-          if (node is null) {
-            return;
-          }
-
-          if (node.RangeToken.Filepath != tok.Filepath || node is Expression { IsImplicit: true } ||
-              node is DefaultValueExpression) {
-            // Ignore any auto-generated expressions.
-          } else {
-            UpdateStartEndToken(node.StartToken);
-            UpdateStartEndToken(node.EndToken);
-          }
-        }
-
-        PreResolveChildren.ForEach(UpdateStartEndTokRecursive);
-
-        if (FormatTokens != null) {
-          foreach (var token in FormatTokens) {
-            UpdateStartEndToken(token);
-          }
-        }
-
-        RangeOrigin = new RangeToken(startTok, endTok);
-      }
-
-      return RangeOrigin;
-    }
-    set => RangeOrigin = value;
-  }
-}
-
-public abstract class RangeNode : Node { // TODO merge into Node when TokenNode is gone.
-
-  public override IOrigin Tok => StartToken; // TODO rename to ReportingToken in separate PR
-
-  public IOrigin tok => Tok; // TODO replace with Tok in separate PR
-
-  // TODO rename to Range in separate PR
-  public override RangeToken RangeToken { get; set; } // TODO remove setter when TokenNode is gone.
-
-  protected RangeNode(Cloner cloner, RangeNode original) {
-    RangeToken = cloner.Tok(original.RangeToken);
-  }
-
-  protected RangeNode(RangeToken rangeOrigin) {
-    RangeToken = rangeOrigin;
-  }
-}
+}
\ No newline at end of file
diff --git a/Source/DafnyCore/Generic/NodeExtensions.cs b/Source/DafnyCore/Generic/NodeExtensions.cs
index 0e843f7ea25..4bf9178c6c8 100644
--- a/Source/DafnyCore/Generic/NodeExtensions.cs
+++ b/Source/DafnyCore/Generic/NodeExtensions.cs
@@ -110,8 +110,8 @@ public static IEnumerable<INode> FindNodesInUris(this INode node, Uri uri) {
   }
 
   public static IEnumerable<LList<INode>> FindNodeChainsInUri(this INode node, Uri uri, LList<INode> parent) {
-    if (node.RangeToken.Uri != null) {
-      if (node.RangeToken.Uri == uri) {
+    if (node.Origin.Uri != null) {
+      if (node.Origin.Uri == uri) {
         return new[] { new LList<INode>(node, parent) };
       }
 
@@ -124,8 +124,8 @@ public static IEnumerable<LList<INode>> FindNodeChainsInUri(this INode node, Uri
 
   private static LList<INode> FindNodeChain(this INode node, Uri uri, DafnyPosition position, LList<INode> parent,
     Func<INode, bool> predicate) {
-    if (node.RangeToken.Uri != null) {
-      if (node.RangeToken.Uri == uri) {
+    if (node.Origin.Uri != null) {
+      if (node.Origin.Uri == uri) {
         return node.FindNodeChain(position, parent, predicate);
       }
 
@@ -151,7 +151,14 @@ public static LList<INode> FindNodeChain(this INode node, DafnyPosition position
 
   private static LList<INode> FindNodeChain(this INode node, DafnyPosition position, LList<INode> parent,
     Func<INode, bool> predicate) {
-    if (node.Tok is AutoGeneratedOrigin || (node.Tok != Token.NoToken && !node.RangeToken.ToDafnyRange().Contains(position))) {
+    if (node.Tok is AutoGeneratedOrigin) {
+      return null;
+    }
+
+    // Example is the default class, although we could give it the same origin as the module it is in.
+    // TODO remove either Token.NoToken or RangeToken.NoToken
+    var fillerNode = node.Origin != Token.NoToken;
+    if (fillerNode && !node.Origin.ToDafnyRange().Contains(position)) {
       return null;
     }
 
diff --git a/Source/DafnyCore/Generic/RangeNode.cs b/Source/DafnyCore/Generic/RangeNode.cs
new file mode 100644
index 00000000000..043f86563e0
--- /dev/null
+++ b/Source/DafnyCore/Generic/RangeNode.cs
@@ -0,0 +1,24 @@
+namespace Microsoft.Dafny;
+
+public abstract class RangeNode : Node {
+  private IOrigin rangeToken; // TODO merge into Node when TokenNode is gone.
+
+  public override IOrigin Tok => Origin; // TODO remove
+
+  public IOrigin tok => Tok; // TODO remove
+
+  // TODO rename to Range in separate PR
+  public override IOrigin RangeOrigin {
+    set => rangeToken = value;
+  } // TODO remove setter when TokenNode is gone.
+
+  public override IOrigin Origin => rangeToken;
+
+  protected RangeNode(Cloner cloner, RangeNode original) {
+    RangeOrigin = cloner.Origin(original.rangeToken);
+  }
+
+  protected RangeNode(IOrigin rangeOrigin) {
+    RangeOrigin = rangeOrigin;
+  }
+}
\ No newline at end of file
diff --git a/Source/DafnyCore/Generic/ReporterExtensions.cs b/Source/DafnyCore/Generic/ReporterExtensions.cs
index 631c1038572..7ed85f62f73 100644
--- a/Source/DafnyCore/Generic/ReporterExtensions.cs
+++ b/Source/DafnyCore/Generic/ReporterExtensions.cs
@@ -54,13 +54,13 @@ private static string FormatRelated(string related) {
 
   public static IEnumerable<DafnyRelatedInformation> CreateDiagnosticRelatedInformationFor(IOrigin token, string? message, bool usingSnippets) {
     var (tokenForMessage, inner, newMessage) = token is NestedOrigin nestedToken ? (nestedToken.Outer, nestedToken.Inner, nestedToken.Message) : (token, null, null);
-    var dafnyToken = BoogieGenerator.ToDafnyToken(true, tokenForMessage);
-    if (!usingSnippets && dafnyToken is RangeToken rangeToken) {
+    var origin = BoogieGenerator.ToDafnyToken(true, tokenForMessage);
+    if (!usingSnippets && origin.ContainsRange) {
       if (message == PostConditionFailingMessage) {
-        var postcondition = rangeToken.PrintOriginal();
+        var postcondition = origin.PrintOriginal();
         message = $"this postcondition might not hold: {postcondition}";
       } else if (message == null || message == RelatedLocationMessage) {
-        message = FormatRelated(rangeToken.PrintOriginal());
+        message = FormatRelated(origin.PrintOriginal());
       }
     }
 
diff --git a/Source/DafnyCore/Generic/TokenNode.cs b/Source/DafnyCore/Generic/TokenNode.cs
new file mode 100644
index 00000000000..c2616dfe5d4
--- /dev/null
+++ b/Source/DafnyCore/Generic/TokenNode.cs
@@ -0,0 +1,93 @@
+using System.Diagnostics;
+using Microsoft.Boogie;
+
+namespace Microsoft.Dafny;
+
+class OriginWithComputedRange : OriginWrapper {
+  private readonly TokenNode node;
+
+  public OriginWithComputedRange(IOrigin center, TokenNode node) : base(center) {
+    this.node = node;
+  }
+
+  public override Token StartToken => RangeToken.StartToken;
+  public override Token EndToken => RangeToken.EndToken;
+  public override bool ContainsRange => true;
+
+  public RangeToken RangeToken {
+    get {
+      if (node.rangeToken == null) {
+
+        var startTok = Center;
+        var endTok = Center;
+
+        void UpdateStartEndToken(Token token1) {
+          if (token1.Filepath != WrappedOrigin.Filepath) {
+            return;
+          }
+
+          if (token1.pos < startTok.pos) {
+            startTok = token1;
+          }
+
+          if (token1.pos + token1.val.Length > endTok.pos + endTok.val.Length) {
+            endTok = token1;
+          }
+        }
+
+        void UpdateStartEndTokRecursive(INode node) {
+          if (node is null) {
+            return;
+          }
+
+          if (node.Origin.Filepath != WrappedOrigin.Filepath || node is Expression { IsImplicit: true } ||
+              node is DefaultValueExpression) {
+            // Ignore any auto-generated expressions.
+          } else {
+            UpdateStartEndToken(node.StartToken);
+            UpdateStartEndToken(node.EndToken);
+          }
+        }
+
+        node.PreResolveChildren.ForEach(UpdateStartEndTokRecursive);
+
+        if (node.FormatTokens != null) {
+          foreach (var token in node.FormatTokens) {
+            UpdateStartEndToken(token);
+          }
+        }
+
+        node.rangeToken = new RangeToken(startTok, endTok);
+      }
+
+      return node.rangeToken;
+    }
+    set => node.rangeToken = value;
+  }
+
+  public override IOrigin WithVal(string newVal) {
+    return new OriginWithComputedRange(Center.WithVal(newVal), node);
+  }
+}
+
+public abstract class TokenNode : Node {
+  // Contains tokens that did not make it in the AST but are part of the expression,
+  // Enables ranges to be correct.
+  // TODO: Re-add format tokens where needed until we put all the formatting to replace the tok of every expression
+  internal Token[] FormatTokens = null;
+
+  public RangeToken rangeToken;
+
+  public IOrigin tok = Token.NoToken;
+
+  [DebuggerBrowsable(DebuggerBrowsableState.Never)]
+  public override IOrigin Tok => tok;
+
+  public override IOrigin RangeOrigin {
+    // TODO do not create new RangeToken.
+    // Let IOrigin also get a RangeToken.
+    set => rangeToken = value == null ? null : new RangeToken(value.StartToken, value.EndToken);
+  }
+
+  public override IOrigin Origin => tok.IsMissingRange ? new OriginWithComputedRange(tok, this) : tok;
+}
\ No newline at end of file
diff --git a/Source/DafnyCore/JsonDiagnostics.cs b/Source/DafnyCore/JsonDiagnostics.cs
index 3eb4562d862..bf4f3f54248 100644
--- a/Source/DafnyCore/JsonDiagnostics.cs
+++ b/Source/DafnyCore/JsonDiagnostics.cs
@@ -6,12 +6,12 @@
 using System.Linq;
 using System.Text.Json;
 using System.Text.Json.Nodes;
+using DafnyCore;
 using VCGeneration;
-using static Microsoft.Dafny.ErrorRegistry;
 
 namespace Microsoft.Dafny;
 
-record DiagnosticMessageData(MessageSource source, ErrorLevel level, Boogie.IToken tok, string? category, string message, List<ErrorInformation.AuxErrorInfo>? related) {
+record DiagnosticMessageData(MessageSource source, ErrorLevel level, IOrigin tok, string? category, string message, List<ErrorInformation.AuxErrorInfo>? related) {
   private static JsonObject SerializePosition(Boogie.IToken tok) {
     return new JsonObject {
       ["pos"] = tok.pos,
@@ -20,23 +20,24 @@ private static JsonObject SerializePosition(Boogie.IToken tok) {
     };
   }
 
-  private static JsonObject SerializeRange(Boogie.IToken tok) {
+  private static JsonObject SerializeRange(DafnyOptions options, IOrigin origin) {
+    var showSnippets = options.Get(Snippets.ShowSnippets);
     var range = new JsonObject {
-      ["start"] = SerializePosition(tok),
+      ["start"] = SerializePosition(showSnippets ? origin.StartToken : origin.Center),
     };
-    if (tok is RangeToken rangeToken1) {
+    if (origin is RangeToken rangeToken1 && showSnippets) {
       range["end"] = SerializePosition(rangeToken1.EndToken);
-    } else if (tok is BoogieRangeOrigin rangeToken2) {
+    } else if (origin is BoogieRangeOrigin rangeToken2 && showSnippets) {
       range["end"] = SerializePosition(rangeToken2.EndToken);
     }
     return range;
   }
 
-  private static JsonObject SerializeToken(Boogie.IToken tok) {
+  private static JsonObject SerializeToken(DafnyOptions options, IOrigin tok) {
     return new JsonObject {
       ["filename"] = tok.filename,
-      ["uri"] = ((IOrigin)tok).Uri.AbsoluteUri,
-      ["range"] = SerializeRange(tok)
+      ["uri"] = tok.Uri.AbsoluteUri,
+      ["range"] = SerializeRange(options, tok)
     };
   }
 
@@ -53,33 +54,34 @@ private static string SerializeMessage(string? category, string message) {
     return category == null ? message : $"{category}: {message}";
   }
 
-  private static JsonObject SerializeRelated(Boogie.IToken tok, string? category, string message) {
+  private static JsonObject SerializeRelated(DafnyOptions options, IOrigin tok, string? category, string message) {
     return new JsonObject {
-      ["location"] = SerializeToken(tok),
+      ["location"] = SerializeToken(options, tok),
       ["message"] = SerializeMessage(category, message),
     };
   }
 
-  private static IEnumerable<JsonNode> SerializeInnerTokens(Boogie.IToken tok) {
+  private static IEnumerable<JsonNode> SerializeInnerTokens(IOrigin tok, DafnyOptions options) {
     while (tok is NestedOrigin nestedToken) {
       tok = nestedToken.Inner;
       var message = nestedToken.Message != null ? "Related location: " + nestedToken.Message : "Related location";
-      yield return SerializeRelated(tok, null, message);
+      yield return SerializeRelated(options, tok, null, message);
     }
   }
 
-  private static IEnumerable<JsonNode> SerializeAuxInfo(ErrorInformation.AuxErrorInfo aux) {
-    yield return SerializeRelated(aux.Tok, aux.Category, aux.Msg);
-    foreach (var n in SerializeInnerTokens(aux.Tok)) {
+  private static IEnumerable<JsonNode> SerializeAuxInfo(ErrorInformation.AuxErrorInfo aux, DafnyOptions options) {
+    var reportRanges = options.Get(Snippets.ShowSnippets);
+    yield return SerializeRelated(options, BoogieGenerator.ToDafnyToken(reportRanges, aux.Tok), aux.Category, aux.Msg);
+    foreach (var n in SerializeInnerTokens(BoogieGenerator.ToDafnyToken(reportRanges, aux.Tok), options)) {
       yield return n;
     }
   }
 
-  public JsonNode ToJson() {
-    var auxRelated = related?.SelectMany(SerializeAuxInfo) ?? Enumerable.Empty<JsonNode>();
-    var innerRelated = SerializeInnerTokens(tok);
+  public JsonNode ToJson(DafnyOptions options) {
+    var auxRelated = related?.SelectMany(aux => SerializeAuxInfo(aux, options)) ?? Enumerable.Empty<JsonNode>();
+    var innerRelated = SerializeInnerTokens(tok, options);
     return new JsonObject {
-      ["location"] = SerializeToken(tok),
+      ["location"] = SerializeToken(options, tok),
       ["severity"] = SerializeErrorLevel(level),
       ["message"] = SerializeMessage(category, message),
       ["source"] = source.ToString(),
@@ -87,22 +89,24 @@ public JsonNode ToJson() {
     };
   }
 
-  public void WriteJsonTo(TextWriter wr) {
-    wr.WriteLine(ToJson().ToJsonString(new JsonSerializerOptions { WriteIndented = false }));
+  public void WriteJsonTo(DafnyOptions options, TextWriter wr) {
+    wr.WriteLine(ToJson(options).ToJsonString(new JsonSerializerOptions { WriteIndented = false }));
   }
 }
 
 public class DafnyJsonConsolePrinter : DafnyConsolePrinter {
   public override void ReportBplError(Boogie.IToken tok, string message, bool error, TextWriter tw, string? category = null) {
     var level = error ? ErrorLevel.Error : ErrorLevel.Warning;
-    new DiagnosticMessageData(MessageSource.Verifier, level, tok, category, message, null).WriteJsonTo(tw);
+    var origin = BoogieGenerator.ToDafnyToken(Options.Get(Snippets.ShowSnippets), tok);
+    new DiagnosticMessageData(MessageSource.Verifier, level, origin, category, message, null).WriteJsonTo(Options, tw);
   }
 
   public override void WriteErrorInformation(VCGeneration.ErrorInformation errorInfo, TextWriter tw, bool skipExecutionTrace = true) {
     var related = errorInfo.Aux.Where(e =>
       !(skipExecutionTrace && (e.Category ?? "").Contains("Execution trace"))).ToList();
+    var dafnyToken = BoogieGenerator.ToDafnyToken(Options.Get(Snippets.ShowSnippets), errorInfo.Tok);
     new DiagnosticMessageData(MessageSource.Verifier, ErrorLevel.Error,
-      errorInfo.Tok, errorInfo.Category, errorInfo.Msg, related).WriteJsonTo(tw);
+      dafnyToken, errorInfo.Category, errorInfo.Msg, related).WriteJsonTo(Options, tw);
     tw.Flush();
   }
 
@@ -113,7 +117,7 @@ public DafnyJsonConsolePrinter(DafnyOptions options) : base(options) {
 public class JsonConsoleErrorReporter : BatchErrorReporter {
   protected override bool MessageCore(MessageSource source, ErrorLevel level, string errorID, Dafny.IOrigin tok, string msg) {
     if (base.MessageCore(source, level, errorID, tok, msg) && (Options is { PrintTooltips: true } || level != ErrorLevel.Info)) {
-      new DiagnosticMessageData(source, level, tok, level == ErrorLevel.Error ? "Error" : null, msg, null).WriteJsonTo(Options.OutputWriter);
+      new DiagnosticMessageData(source, level, tok, level == ErrorLevel.Error ? "Error" : null, msg, null).WriteJsonTo(Options, Options.OutputWriter);
       return true;
     }
 
diff --git a/Source/DafnyCore/Pipeline/BoogieExtensions.cs b/Source/DafnyCore/Pipeline/BoogieExtensions.cs
index 3477a1dce0a..f01e1eb800e 100644
--- a/Source/DafnyCore/Pipeline/BoogieExtensions.cs
+++ b/Source/DafnyCore/Pipeline/BoogieExtensions.cs
@@ -24,16 +24,6 @@ public static Range ToLspRange(this DafnyRange range) {
         range.ExclusiveEnd.GetLspPosition());
     }
 
-    /// <summary>
-    /// Gets the LSP range of the specified token.
-    /// </summary>
-    /// <param name="startToken">The token to get the range of.</param>
-    /// <param name="endToken">An optional other token to get the end of the range of.</param>
-    /// <returns>The LSP range of the token.</returns>
-    public static Range ToLspRange(this RangeToken range) {
-      return range.ToDafnyRange().ToLspRange();
-    }
-
     /// <summary>
     /// Gets the LSP range of the specified token.
     /// </summary>
@@ -61,11 +51,18 @@ public static Range GetLspRange(this Boogie.IToken token, bool nameRange = false
       if (token is NestedOrigin nestedToken) {
         return GetLspRange(nestedToken.Outer, nameRange);
       }
-      var dafnyToken = BoogieGenerator.ToDafnyToken(!nameRange, token);
-      if (dafnyToken is RangeToken rangeToken) {
-        return GetLspRangeGeneric(rangeToken.StartToken, rangeToken.EndToken);
-      }
-      return GetLspRangeGeneric(token, token);
+      var origin = BoogieGenerator.ToDafnyToken(!nameRange, token);
+      return GetLspRange(origin);
+    }
+
+    /// <summary>
+    /// Gets the LSP range of the specified token.
+    /// </summary>
+    /// <param name="token">The token to get the range of.</param>
+    /// <param name="endToken">An optional other token to get the end of the range of.</param>
+    /// <returns>The LSP range of the token.</returns>
+    public static Range GetLspRange(this IOrigin origin) {
+      return GetLspRangeGeneric(origin.StartToken, origin.EndToken);
     }
 
     public static Position GetLspPosition(this DafnyPosition position) {
@@ -79,10 +76,10 @@ public static Location GetLocation(this IOrigin token) {
       };
     }
 
-    public static Location GetLocation(this RangeToken origin) {
+    public static Location GetLocation(this RangeToken token) {
       return new Location() {
-        Uri = DocumentUri.From(origin.Uri),
-        Range = origin.GetLspRange()
+        Uri = DocumentUri.From(token.Uri),
+        Range = token.GetLspRange()
       };
     }
 
diff --git a/Source/DafnyCore/Pipeline/Compilation.cs b/Source/DafnyCore/Pipeline/Compilation.cs
index 863fbd7adab..ab6e5cd8e5e 100644
--- a/Source/DafnyCore/Pipeline/Compilation.cs
+++ b/Source/DafnyCore/Pipeline/Compilation.cs
@@ -47,7 +47,10 @@ public class Compilation : IDisposable {
   private readonly LazyConcurrentDictionary<ModuleDefinition,
     Task<IReadOnlyDictionary<FilePosition, IReadOnlyList<IVerificationTask>>>> translatedModules = new();
 
-  private readonly ConcurrentDictionary<ICanVerify, Unit> verifyingOrVerifiedSymbols = new();
+  /// <summary>
+  /// We use file positions as keys, because nodes are transformed throughout the compilation pipeline
+  /// </summary>
+  private readonly ConcurrentDictionary<FilePosition, Unit> verifyingOrVerifiedSymbols = new();
   private readonly LazyConcurrentDictionary<ICanVerify, IReadOnlyList<IVerificationTask>> tasksPerVerifiable = new();
 
   public DafnyOptions Options => Input.Options;
@@ -296,7 +299,7 @@ public async Task<bool> VerifyLocation(FilePosition verifiableLocation, Func<IVe
   }
 
   private async Task<bool> VerifyCanVerify(ICanVerify canVerify, Func<IVerificationTask, bool> taskFilter,
-    int? randomSeed = 0,
+    int? randomSeed = null,
     bool onlyPrepareVerificationForGutterTests = false) {
 
     var resolution = await Resolution;
@@ -309,7 +312,9 @@ private async Task<bool> VerifyCanVerify(ICanVerify canVerify, Func<IVerificatio
       return false;
     }
 
-    if (!onlyPrepareVerificationForGutterTests && (randomSeed == null && !verifyingOrVerifiedSymbols.TryAdd(canVerify, Unit.Default))) {
+    var key = canVerify.NavigationToken.GetFilePosition();
+
+    if (!onlyPrepareVerificationForGutterTests && randomSeed == null && !verifyingOrVerifiedSymbols.TryAdd(key, Unit.Default)) {
       return false;
     }
 
@@ -433,7 +438,9 @@ public async Task Cancel(FilePosition filePosition) {
       foreach (var view in implementations) {
         view.Cancel();
       }
-      verifyingOrVerifiedSymbols.TryRemove(canVerify, out _);
+
+      var key = canVerify.NavigationToken.GetFilePosition();
+      verifyingOrVerifiedSymbols.TryRemove(key, out _);
     }
   }
 
diff --git a/Source/DafnyCore/Pipeline/TextDocumentLoader.cs b/Source/DafnyCore/Pipeline/TextDocumentLoader.cs
index 60748398ea6..3d200f380f5 100644
--- a/Source/DafnyCore/Pipeline/TextDocumentLoader.cs
+++ b/Source/DafnyCore/Pipeline/TextDocumentLoader.cs
@@ -61,7 +61,7 @@ public async Task<ProgramParseResult> ParseAsync(Compilation compilation, Cancel
         verifiables = null;
       } else {
         var symbols = SymbolExtensions.GetSymbolDescendants(program.DefaultModule);
-        verifiables = symbols.OfType<ICanVerify>().Where(v => !v.RangeToken.IsCopy &&
+        verifiables = symbols.OfType<ICanVerify>().Where(v => !v.Origin.IsCopy &&
                                                               v.ContainingModule.ShouldVerify(program.Compilation) &&
                                                               v.ShouldVerify(program.Compilation) &&
                                                               v.ShouldVerify).ToList();
diff --git a/Source/DafnyCore/ProofDependencyWarnings.cs b/Source/DafnyCore/ProofDependencyWarnings.cs
index b26e2a4d105..e93ca12c12b 100644
--- a/Source/DafnyCore/ProofDependencyWarnings.cs
+++ b/Source/DafnyCore/ProofDependencyWarnings.cs
@@ -160,12 +160,23 @@ private static void SuggestByProofRefactoring(string scopeName,
 
       manager.ProofDependenciesById.TryGetValue(partialAssert!.Id, out var assertDepProvenByFact);
 
-      var factAlreadyInByBlock = assertDepProvenByFact != null && (fact == assertDepProvenByFact || assertDepProvenByFact.Range.Intersects(fact.Range));
-      if (factAlreadyInByBlock) {
+
+      var factAlreadyInByBlock1 = assertDepProvenByFact != null && assertDepProvenByFact.Range.Contains(fact.Range);
+      if (factAlreadyInByBlock1) {
+        continue;
+      }
+
+      var factAlreadyInByBlock2 = assertDepProvenByFact is ProofObligationDependency { ProofObligation: AssertStatementDescription assertStatementDescription }
+                                  && assertStatementDescription.AssertStatement.Origin.Contains(fact.Range);
+      if (factAlreadyInByBlock2) {
+        continue;
+      }
+
+      if (fact == assertDepProvenByFact) {
         continue;
       }
 
-      RangeToken range = null;
+      IOrigin range = null;
       var factProvider = "";
       var factConsumer = "";
       var recommendation = "";
@@ -190,7 +201,7 @@ private static void SuggestByProofRefactoring(string scopeName,
 
       switch (assertDepProvenByFact) {
         case CallDependency call: {
-            factConsumer = $"precondtion{(call.call.Method.Req.Count > 1 ? "s" : "")} of the method call {call.Range.Next.TokenToString(options)}";
+            factConsumer = $"precondition{(call.call.Method.Req.Count > 1 ? "s" : "")} of the method call {call.Range.Next.TokenToString(options)}";
             break;
           }
         case ProofObligationDependency { ProofObligation: AssertStatementDescription }: {
diff --git a/Source/DafnyCore/Resolver/AmbiguousMemberDecl.cs b/Source/DafnyCore/Resolver/AmbiguousMemberDecl.cs
index 1379864e655..3da22bb860b 100644
--- a/Source/DafnyCore/Resolver/AmbiguousMemberDecl.cs
+++ b/Source/DafnyCore/Resolver/AmbiguousMemberDecl.cs
@@ -37,7 +37,7 @@ public override string GetDescription(DafnyOptions options) {
   ISet<MemberDecl> IAmbiguousThing<MemberDecl>.Pool => pool;
 
   private AmbiguousMemberDecl(ModuleDefinition m, string name, ISet<MemberDecl> pool)
-    : base(pool.First().RangeToken, new Name(pool.First().RangeToken, name), true, pool.First().IsGhost, null, false) {
+    : base(pool.First().Origin, new Name(pool.First().Origin, name), true, pool.First().IsGhost, null, false) {
     Contract.Requires(name != null);
     Contract.Requires(pool != null && 2 <= pool.Count);
     this.pool = pool;
diff --git a/Source/DafnyCore/Resolver/AmbiguousTopLevelDecl.cs b/Source/DafnyCore/Resolver/AmbiguousTopLevelDecl.cs
index 0317957f73a..f284452f6c0 100644
--- a/Source/DafnyCore/Resolver/AmbiguousTopLevelDecl.cs
+++ b/Source/DafnyCore/Resolver/AmbiguousTopLevelDecl.cs
@@ -42,7 +42,7 @@ public override string GetDescription(DafnyOptions options) {
   ISet<TopLevelDecl> IAmbiguousThing<TopLevelDecl>.Pool => pool;
 
   private AmbiguousTopLevelDecl(ModuleDefinition m, string name, ISet<TopLevelDecl> pool)
-    : base(pool.First().RangeToken, new Name(pool.First().RangeToken, name), m, new List<TypeParameter>(), null, false) {
+    : base(pool.First().Origin, new Name(pool.First().Origin, name), m, new List<TypeParameter>(), null, false) {
     Contract.Requires(name != null);
     Contract.Requires(pool != null && 2 <= pool.Count);
     this.pool = pool;
diff --git a/Source/DafnyCore/Resolver/BoundsDiscovery/BoundsDiscovery.cs b/Source/DafnyCore/Resolver/BoundsDiscovery/BoundsDiscovery.cs
index 137a9f10e91..0b2e4de385e 100644
--- a/Source/DafnyCore/Resolver/BoundsDiscovery/BoundsDiscovery.cs
+++ b/Source/DafnyCore/Resolver/BoundsDiscovery/BoundsDiscovery.cs
@@ -151,7 +151,7 @@ public static Expression FrameArrowToObjectSet(Expression e) {
         var objUse = new IdentifierExpr(e.tok, objVar.Name) { Type = objVar.Type, Var = objVar };
         boundVarDecls.Add(objVar);
 
-        var collection = new ApplyExpr(e.tok, e, boundVarUses, e.tok) {
+        var collection = new ApplyExpr(e.tok, e, boundVarUses, Token.NoToken) {
           Type = collectionType
         };
         var resolvedOpcode = collectionType.ResolvedOpcodeForIn;
@@ -162,7 +162,7 @@ public static Expression FrameArrowToObjectSet(Expression e) {
         };
 
         var attributes = new Attributes("_reads", new List<Expression>(), null);
-        return new SetComprehension(e.tok, e.RangeToken, true, boundVarDecls, inCollection, objUse, attributes) {
+        return new SetComprehension(e.tok, e.Origin, true, boundVarDecls, inCollection, objUse, attributes) {
           Type = new SetType(true, elementType)
         };
       }
diff --git a/Source/DafnyCore/Resolver/CallGraphBuilder.cs b/Source/DafnyCore/Resolver/CallGraphBuilder.cs
index 4f193d74e9d..262c7b02ad7 100644
--- a/Source/DafnyCore/Resolver/CallGraphBuilder.cs
+++ b/Source/DafnyCore/Resolver/CallGraphBuilder.cs
@@ -224,7 +224,7 @@ protected override bool VisitOneStatement(Statement stmt, CallGraphBuilderContex
                 !currentMethod.AssignedAssumptionVariables.Contains(localVar)) {
               currentMethod.AssignedAssumptionVariables.Add(localVar);
             } else {
-              reporter.Error(MessageSource.Resolver, stmt,
+              reporter.Error(MessageSource.Resolver, assignStmt,
                 $"there may be at most one assignment to an assumption variable, the RHS of which must match the expression \"{localVar.Name} && <boolean expression>\"");
             }
           }
diff --git a/Source/DafnyCore/Resolver/InferDecreasesClause.cs b/Source/DafnyCore/Resolver/InferDecreasesClause.cs
index 452839f0115..3a61420cbe6 100644
--- a/Source/DafnyCore/Resolver/InferDecreasesClause.cs
+++ b/Source/DafnyCore/Resolver/InferDecreasesClause.cs
@@ -104,11 +104,11 @@ public bool FillInDefaultDecreases(ICallable clbl, bool addPrefixInCoClusters) {
 
       // Add one component for each parameter, unless the parameter's type is one that
       // doesn't appear useful to orderings.
-      foreach (var p in clbl.Ins) {
-        if (!(p is ImplicitFormal) && p.Type.IsOrdered) {
-          var ie = new IdentifierExpr(new AutoGeneratedOrigin(p.tok), p.Name);
-          ie.Var = p;
-          ie.Type = p.Type; // resolve it here
+      foreach (var formal in clbl.Ins) {
+        if (formal is not ImplicitFormal && formal.Type.IsOrdered) {
+          var ie = new IdentifierExpr(formal.StartToken.MakeAutoGenerated(), formal.Name);
+          ie.Var = formal;
+          ie.Type = formal.Type; // resolve it here
           decr.Add(AutoGeneratedExpression.Create(ie));
           anyChangeToDecreases = true;
         }
@@ -177,7 +177,7 @@ public Expression FrameToObjectSet(List<FrameExpression> fexprs) {
           ResolvedOp = resolvedOpcode,
           Type = Type.Bool
         };
-        var s = new SetComprehension(e.tok, e.RangeToken, true, new List<BoundVar>() { bvDecl }, bvInE, bv,
+        var s = new SetComprehension(e.tok, e.Origin, true, new List<BoundVar>() { bvDecl }, bvInE, bv,
           new Attributes("trigger", new List<Expression> { bvInE }, null)) {
           Type = resolver.SystemModuleManager.ObjectSetType(),
           Bounds = new List<BoundedPool>() { boundedPool }
diff --git a/Source/DafnyCore/Resolver/ModuleResolver.cs b/Source/DafnyCore/Resolver/ModuleResolver.cs
index ade4003df23..2ee87601a73 100644
--- a/Source/DafnyCore/Resolver/ModuleResolver.cs
+++ b/Source/DafnyCore/Resolver/ModuleResolver.cs
@@ -782,9 +782,8 @@ public void RegisterByMethod(Function f, TopLevelDeclWithMembers cl) {
       var receiver = isStatic ? (Expression)new StaticReceiverExpr(tok, cl, true) : new ImplicitThisExpr(tok);
       var fn = new ApplySuffix(tok, null,
         new ExprDotName(tok, receiver, f.Name, f.TypeArgs.ConvertAll(typeParameter => (Type)new UserDefinedType(f.tok, typeParameter))),
-        new ActualBindings(f.Ins.ConvertAll(Expression.CreateIdentExpr)).ArgumentBindings,
-        tok);
-      var post = new AttributedExpression(new BinaryExpr(tok, BinaryExpr.Opcode.Eq, r, fn));
+        new ActualBindings(f.Ins.ConvertAll(Expression.CreateIdentExpr)).ArgumentBindings, Token.NoToken);
+      var post = new AttributedExpression(tok, new BinaryExpr(tok, BinaryExpr.Opcode.Eq, r, fn));
       Specification<FrameExpression> reads;
       if (Options.Get(Method.ReadsClausesOnMethods)) {
         // If f.Reads is empty, replace it with an explicit `reads {}` so that we don't replace that
@@ -801,7 +800,9 @@ public void RegisterByMethod(Function f, TopLevelDeclWithMembers cl) {
         reads = new Specification<FrameExpression>();
       }
 
-      var method = new Method(f.RangeToken.MakeAutoGenerated(), new Name(new AutoGeneratedOrigin(f.NameNode.Tok)), f.HasStaticKeyword, false, f.TypeArgs,
+      var method = new Method(f.Origin.MakeAutoGenerated(),
+        new Name(f.NameNode.Tok.MakeAutoGenerated(), f.Name),
+        f.HasStaticKeyword, false, f.TypeArgs,
         f.Ins, new List<Formal>() { resultVar },
         f.Req, reads, new Specification<FrameExpression>(new List<FrameExpression>(), null), new List<AttributedExpression>() { post }, f.Decreases,
         f.ByMethodBody, f.Attributes, null, true);
@@ -868,7 +869,7 @@ TopLevelDecl CloneDeclarationForAbstractSignature(VisibilityScope scope, TopLeve
 
       if (d is AbstractModuleDecl abstractDecl) {
         var sig = MakeAbstractSignature(abstractDecl.OriginalSignature, name + "." + abstractDecl.Name, abstractDecl.Height, mods);
-        var result = new AbstractModuleDecl(abstractDecl.Options, abstractDecl.RangeToken, abstractDecl.QId, abstractDecl.NameNode,
+        var result = new AbstractModuleDecl(abstractDecl.Options, abstractDecl.Origin, abstractDecl.QId, abstractDecl.NameNode,
           newParent, abstractDecl.Opened, abstractDecl.Exports, Guid.NewGuid()) {
           Signature = sig,
           OriginalSignature = abstractDecl.OriginalSignature
@@ -1695,7 +1696,7 @@ private void FillInPostConditionsAndBodiesOfPrefixLemmas(List<TopLevelDecl> decl
             var subst = new ExtremeLemmaSpecificationSubstituter(coConclusions, new IdentifierExpr(k.tok, k.Name),
               this.reporter, true);
             var post = subst.CloneExpr(p.E);
-            prefixLemma.Ens.Add(new AttributedExpression(post));
+            prefixLemma.Ens.Add(new AttributedExpression(post.Origin, post));
             foreach (var e in coConclusions) {
               if (e is FunctionCallExpr fce) {
                 GreatestPredicate predicate = (GreatestPredicate)fce.Function;
@@ -1722,7 +1723,7 @@ private void FillInPostConditionsAndBodiesOfPrefixLemmas(List<TopLevelDecl> decl
             var subst = new ExtremeLemmaSpecificationSubstituter(antecedents, new IdentifierExpr(k.tok, k.Name),
               this.reporter, false);
             var pre = subst.CloneExpr(p.E);
-            prefixLemma.Req.Add(new AttributedExpression(pre, p.Label, null));
+            prefixLemma.Req.Add(new AttributedExpression(pre.Origin, pre, p.Label, null));
             foreach (var e in antecedents) {
               var fce = (FunctionCallExpr)e; // we expect "antecedents" to contain only FunctionCallExpr's
               LeastPredicate predicate = (LeastPredicate)fce.Function;
@@ -1792,7 +1793,7 @@ private void FillInPostConditionsAndBodiesOfPrefixLemmas(List<TopLevelDecl> decl
             methodSel.TypeApplicationJustMember =
               prefixLemma.TypeArgs.ConvertAll(tp => (Type)new UserDefinedType(tp.tok, tp));
             methodSel.Type = new InferredTypeProxy();
-            var recursiveCall = new CallStmt(com.RangeToken, new List<Expression>(), methodSel,
+            var recursiveCall = new CallStmt(com.Origin, new List<Expression>(), methodSel,
               recursiveCallArgs.ConvertAll(e => new ActualBinding(null, e)));
             recursiveCall.IsGhost = prefixLemma.IsGhost; // resolve here
 
@@ -1805,18 +1806,18 @@ private void FillInPostConditionsAndBodiesOfPrefixLemmas(List<TopLevelDecl> decl
             attrs = new Attributes("_trustWellformed", new List<Expression>(), attrs);
 #endif
             attrs = new Attributes("auto_generated", new List<Expression>(), attrs);
-            var forallBody = new BlockStmt(mainBody.RangeToken, new List<Statement>() { recursiveCall });
-            var forallStmt = new ForallStmt(mainBody.RangeToken, bvs, attrs, range,
+            var forallBody = new BlockStmt(mainBody.Origin, new List<Statement>() { recursiveCall });
+            var forallStmt = new ForallStmt(mainBody.Origin, bvs, attrs, range,
               new List<AttributedExpression>(), forallBody);
-            els = new BlockStmt(mainBody.RangeToken, new List<Statement>() { forallStmt });
+            els = new BlockStmt(mainBody.Origin, new List<Statement>() { forallStmt });
           } else {
             kk = new IdentifierExpr(k.tok, k.Name);
             els = null;
           }
 
           var kPositive = new BinaryExpr(com.tok, BinaryExpr.Opcode.Lt, new LiteralExpr(com.tok, 0), kk);
-          var condBody = new IfStmt(mainBody.RangeToken, false, kPositive, mainBody, els);
-          prefixLemma.Body = new BlockStmt(mainBody.RangeToken, new List<Statement>() { condBody });
+          var condBody = new IfStmt(mainBody.Origin, false, kPositive, mainBody, els);
+          prefixLemma.Body = new BlockStmt(mainBody.Origin, new List<Statement>() { condBody });
         }
 
         // The prefix lemma now has all its components, so it's finally time we resolve it
@@ -3141,18 +3142,18 @@ internal Type ResolvedArrayType(IOrigin tok, int dims, Type arg, ResolutionConte
     }
 
     public Expression VarDotMethod(IOrigin tok, string varname, string methodname) {
-      return new ApplySuffix(tok, null, new ExprDotName(tok, new IdentifierExpr(tok, varname), methodname, null), new List<ActualBinding>(), tok);
+      return new ApplySuffix(tok, null, new ExprDotName(tok, new IdentifierExpr(tok, varname), methodname, null), new List<ActualBinding>(), Token.NoToken);
     }
 
     public Expression makeTemp(String prefix, AssignOrReturnStmt s, ResolutionContext resolutionContext, Expression ex) {
       var temp = FreshTempVarName(prefix, resolutionContext.CodeContext);
-      var locvar = new LocalVariable(s.RangeToken, temp, ex.Type, false);
+      var locvar = new LocalVariable(s.Origin, temp, ex.Type, false);
       var id = new IdentifierExpr(s.Tok, temp);
       var idlist = new List<Expression>() { id };
       var lhss = new List<LocalVariable>() { locvar };
       var rhss = new List<AssignmentRhs>() { new ExprRhs(ex) };
-      var up = new AssignStatement(s.RangeToken, idlist, rhss);
-      s.ResolvedStatements.Add(new VarDeclStmt(s.RangeToken, lhss, up));
+      var up = new AssignStatement(s.Origin, idlist, rhss);
+      s.ResolvedStatements.Add(new VarDeclStmt(s.Origin, lhss, up));
       return id;
     }
 
@@ -3320,7 +3321,7 @@ public static UserDefinedType GetReceiverType(IOrigin tok, MemberDecl member) {
     }
 
     internal Expression VarDotFunction(IOrigin tok, string varname, string functionname) {
-      return new ApplySuffix(tok, null, new ExprDotName(tok, new IdentifierExpr(tok, varname), functionname, null), new List<ActualBinding>(), tok);
+      return new ApplySuffix(tok, null, new ExprDotName(tok, new IdentifierExpr(tok, varname), functionname, null), new List<ActualBinding>(), Token.NoToken);
     }
 
     // TODO search for occurrences of "new LetExpr" which could benefit from this helper
diff --git a/Source/DafnyCore/Resolver/NameResolutionAndTypeInference/NameResolutionAndTypeInference.cs b/Source/DafnyCore/Resolver/NameResolutionAndTypeInference/NameResolutionAndTypeInference.cs
index d8c364a604a..9fd64d8c29c 100644
--- a/Source/DafnyCore/Resolver/NameResolutionAndTypeInference/NameResolutionAndTypeInference.cs
+++ b/Source/DafnyCore/Resolver/NameResolutionAndTypeInference/NameResolutionAndTypeInference.cs
@@ -423,9 +423,9 @@ public void ResolveExpressionX(Expression expr, ResolutionContext resolutionCont
       if (expr is ParensExpression) {
         var e = (ParensExpression)expr;
         ResolveExpression(e.E, resolutionContext);
-        var innerRange = e.E.RangeToken;
+        var innerRange = e.E.Origin;
         e.ResolvedExpression = e.E; // Overwrites the range, which is not suitable for ParensExpressions
-        e.E.RangeToken = innerRange;
+        e.E.RangeOrigin = innerRange;
         e.Type = e.E.Type;
 
       } else if (expr is ChainingExpression) {
@@ -2778,10 +2778,10 @@ void ResolveClassMemberBodies(TopLevelDeclWithMembers cl) {
       foreach (MemberDecl member in cl.Members) {
         Contract.Assert(VisibleInScope(member));
         if (member.HasUserAttribute("only", out var attribute)) {
-          reporter.Warning(MessageSource.Verifier, ResolutionErrors.ErrorId.r_member_only_assumes_other.ToString(), attribute.RangeToken.ToToken(),
+          reporter.Warning(MessageSource.Verifier, ResolutionErrors.ErrorId.r_member_only_assumes_other.ToString(), attribute.Origin,
             "Members with {:only} temporarily disable the verification of other members in the entire file");
           if (attribute.Args.Count >= 1) {
-            reporter.Warning(MessageSource.Verifier, ResolutionErrors.ErrorId.r_member_only_has_no_before_after.ToString(), attribute.Args[0].RangeToken.ToToken(),
+            reporter.Warning(MessageSource.Verifier, ResolutionErrors.ErrorId.r_member_only_has_no_before_after.ToString(), attribute.Args[0].Origin,
               "{:only} on members does not support arguments");
           }
         }
@@ -3142,7 +3142,7 @@ void ResolveCallStmt(CallStmt s, ResolutionContext resolutionContext, Type recei
       bool tryToResolve = false;
       if (callee.Outs.Count != s.Lhs.Count) {
         if (isInitCall) {
-          reporter.Error(MessageSource.Resolver, s, "a method called as an initialization method must not have any result arguments");
+          reporter.Error(MessageSource.Resolver, s.MethodSelect, "a method called as an initialization method must not have any result arguments");
         } else {
           reporter.Error(MessageSource.Resolver, s,
             "the method returns {1} value{3} but is assigned to {0} variable{2} (all return values must be assigned)",
@@ -3564,7 +3564,7 @@ public void ResolveStatement(Statement stmt, ResolutionContext resolutionContext
             foreach (Formal f in cmc.Outs) {
               Expression produceLhs;
               if (stmt is ReturnStmt) {
-                var ident = new ImplicitIdentifierExpr(f.tok, f.Name);
+                var ident = new ImplicitIdentifierExpr(stmt.Tok.MakeAutoGenerated(), f.Name);
                 // resolve it here to avoid capture into more closely declared local variables
                 ident.Var = f;
                 ident.Type = ident.Var.Type;
@@ -3577,7 +3577,7 @@ public void ResolveStatement(Statement stmt, ResolutionContext resolutionContext
               }
               formals.Add(produceLhs);
             }
-            s.HiddenUpdate = new AssignStatement(s.RangeToken, formals, s.Rhss, true);
+            s.HiddenUpdate = new AssignStatement(s.Origin, formals, s.Rhss, true);
             // resolving the update statement will check for return/yield statement specifics.
             ResolveStatement(s.HiddenUpdate, resolutionContext);
           }
@@ -3866,7 +3866,7 @@ public void ResolveStatement(Statement stmt, ResolutionContext resolutionContext
               s.Kind = ForallStmt.BodyKind.Proof;
               // add the conclusion of the calc as a free postcondition
               var result = ((CalcStmt)s0).Result;
-              s.Ens.Add(new AttributedExpression(result));
+              s.Ens.Add(new AttributedExpression(result.Origin, result));
               reporter.Info(MessageSource.Resolver, s.Tok, "ensures " + Printer.ExprToString(Options, result));
             } else {
               s.Kind = ForallStmt.BodyKind.Proof;
@@ -4272,7 +4272,7 @@ static void FillInTypeArguments(IOrigin tok, int n, List<Type> typeArgs, List<Ty
           // extend defaultTypeArguments, if needed
           for (int i = defaultTypeArguments.Count; i < n; i++) {
             var parentToken = option.Parent.Tok;
-            var tp = new TypeParameter(parentToken.ToRange(), new Name(parentToken.ToRange(), "_T" + i), i, option.Parent);
+            var tp = new TypeParameter(parentToken, new Name(parentToken, "_T" + i), i, option.Parent);
             if (option.Parent is IteratorDecl) {
               tp.Characteristics.AutoInit = Type.AutoInitInfo.CompilableValue;
             }
@@ -4413,13 +4413,13 @@ public void ResolveTypeRhs(TypeRhs rr, Statement stmt, ResolutionContext resolut
               // We want to create a MemberSelectExpr for the initializing method.  To do that, we create a throw-away receiver of the appropriate
               // type, create a dot-suffix expression around this receiver, and then resolve it in the usual way for dot-suffix expressions.
               var lhs = new ImplicitThisExpr_ConstructorCall(initCallTok) { Type = rr.EType };
-              var callLhs = new ExprDotName(((UserDefinedType)rr.EType).tok, lhs, initCallName, ret == null ? null : ret.LastComponent.OptTypeArguments);
+              var callLhs = new ExprDotName(rr.Path.Origin, lhs, initCallName, ret == null ? null : ret.LastComponent.OptTypeArguments);
               ResolveDotSuffix(callLhs, false, true, rr.Bindings.ArgumentBindings, resolutionContext, true);
               if (prevErrorCount == reporter.Count(ErrorLevel.Error)) {
                 Contract.Assert(callLhs.ResolvedExpression is MemberSelectExpr);  // since ResolveApplySuffix succeeded and call.Lhs denotes an expression (not a module or a type)
                 var methodSel = (MemberSelectExpr)callLhs.ResolvedExpression;
                 if (methodSel.Member is Method) {
-                  rr.InitCall = new CallStmt(stmt.RangeToken, new List<Expression>(), methodSel, rr.Bindings.ArgumentBindings, initCallTok);
+                  rr.InitCall = new CallStmt(stmt.Origin, new List<Expression>(), methodSel, rr.Bindings.ArgumentBindings, initCallTok);
                   ResolveCallStmt(rr.InitCall, resolutionContext, rr.EType);
                 } else {
                   reporter.Error(MessageSource.Resolver, initCallTok, "object initialization must denote an initializing method or constructor ({0})", initCallName);
@@ -5894,7 +5894,7 @@ public MethodCallInformation ResolveApplySuffix(ApplySuffix e, ResolutionContext
               }
               if (allowMethodCall) {
                 Contract.Assert(!e.Bindings.WasResolved); // we expect that .Bindings has not yet been processed, so we use just .ArgumentBindings in the next line
-                var tok = Options.Get(Snippets.ShowSnippets) ? e.RangeToken.ToToken() : e.tok;
+                var tok = Options.Get(Snippets.ShowSnippets) ? e.Origin : e.tok;
                 var cRhs = new MethodCallInformation(tok, mse, e.Bindings.ArgumentBindings);
                 return cRhs;
               } else {
@@ -5917,7 +5917,7 @@ public MethodCallInformation ResolveApplySuffix(ApplySuffix e, ResolutionContext
           }
           if (callee != null) {
             // produce a FunctionCallExpr instead of an ApplyExpr(MemberSelectExpr)
-            var rr = new FunctionCallExpr(e.Lhs.Tok, callee.Name, mse.Obj, e.tok, e.CloseParen, e.Bindings, atLabel) {
+            var rr = new FunctionCallExpr(e.Lhs.Tok, callee.Name, mse.Obj, Token.NoToken, e.CloseParen, e.Bindings, atLabel) {
               Function = callee,
               TypeApplication_AtEnclosingClass = mse.TypeApplicationAtEnclosingClass,
               TypeApplication_JustFunction = mse.TypeApplicationJustMember
diff --git a/Source/DafnyCore/Resolver/PreType/PreTypeResolve.Expressions.cs b/Source/DafnyCore/Resolver/PreType/PreTypeResolve.Expressions.cs
index 5f95a66103f..5ef4df4bac0 100644
--- a/Source/DafnyCore/Resolver/PreType/PreTypeResolve.Expressions.cs
+++ b/Source/DafnyCore/Resolver/PreType/PreTypeResolve.Expressions.cs
@@ -1756,7 +1756,7 @@ public MethodCallInformation ResolveApplySuffix(ApplySuffix e, ResolutionContext
           }
           if (callee != null) {
             // resolve as a FunctionCallExpr instead of as an ApplyExpr(MemberSelectExpr)
-            var rr = new FunctionCallExpr(e.Lhs.tok, callee.Name, mse.Obj, e.tok, e.CloseParen, e.Bindings, atLabel) {
+            var rr = new FunctionCallExpr(e.Lhs.tok, callee.Name, mse.Obj, Token.NoToken, e.CloseParen, e.Bindings, atLabel) {
               Function = callee,
               PreTypeApplication_AtEnclosingClass = mse.PreTypeApplicationAtEnclosingClass,
               PreTypeApplication_JustFunction = mse.PreTypeApplicationJustMember
@@ -1810,7 +1810,7 @@ public MethodCallInformation ResolveApplySuffix(ApplySuffix e, ResolutionContext
               }
               if (allowMethodCall) {
                 Contract.Assert(!e.Bindings.WasResolved); // we expect that .Bindings has not yet been processed, so we use just .ArgumentBindings in the next line
-                var tok = resolver.Options.Get(Snippets.ShowSnippets) ? e.RangeToken.ToToken() : e.tok;
+                var tok = resolver.Options.Get(Snippets.ShowSnippets) ? e.Origin : e.tok;
                 e.MethodCallInfo = new MethodCallInformation(tok, mse, e.Bindings.ArgumentBindings);
                 return e.MethodCallInfo;
               } else {
diff --git a/Source/DafnyCore/Resolver/PreType/PreTypeResolve.Statements.cs b/Source/DafnyCore/Resolver/PreType/PreTypeResolve.Statements.cs
index 7a7fff8a245..34e9fe57588 100644
--- a/Source/DafnyCore/Resolver/PreType/PreTypeResolve.Statements.cs
+++ b/Source/DafnyCore/Resolver/PreType/PreTypeResolve.Statements.cs
@@ -182,7 +182,7 @@ public void ResolveStatement(Statement stmt, ResolutionContext resolutionContext
               }
               formals.Add(produceLhs);
             }
-            s.HiddenUpdate = new AssignStatement(s.RangeToken, formals, s.Rhss, true);
+            s.HiddenUpdate = new AssignStatement(s.Origin, formals, s.Rhss, true);
             // resolving the update statement will check for return/yield statement specifics.
             ResolveStatement(s.HiddenUpdate, resolutionContext);
           }
@@ -350,7 +350,7 @@ public void ResolveStatement(Statement stmt, ResolutionContext resolutionContext
               s.Kind = ForallStmt.BodyKind.Proof;
               // add the conclusion of the calc as a free postcondition
               var result = ((CalcStmt)s0).Result;
-              s.Ens.Add(new AttributedExpression(result));
+              s.Ens.Add(new AttributedExpression(result.Origin, result));
               ReportInfo(s.Tok, "ensures " + Printer.ExprToString(resolver.Options, result));
             } else {
               s.Kind = ForallStmt.BodyKind.Proof;
@@ -580,7 +580,7 @@ private void ResolveConcreteUpdateStmt(ConcreteAssignStatement assign, List<Loca
         }
 
         if (assign is AssignStatement updateStmt) {
-          ResolveUpdateStmt(updateStmt, resolutionContext, errorCountBeforeCheckingStmt);
+          ResolveAssignStmt(updateStmt, resolutionContext, errorCountBeforeCheckingStmt);
         } else if (assign is AssignOrReturnStmt assignOrReturnStmt) {
           ResolveAssignOrReturnStmt(assignOrReturnStmt, resolutionContext);
         } else {
@@ -613,7 +613,7 @@ void ResolveAssignmentRhs(AssignmentRhs rhs, Statement enclosingStmt, Resolution
     /// errorCountBeforeCheckingStmt is passed in so that this method can determine if any resolution errors were found during
     /// LHS or RHS checking, because only if no errors were found is update.ResolvedStmt changed.
     /// </summary>
-    private void ResolveUpdateStmt(AssignStatement update, ResolutionContext resolutionContext,
+    private void ResolveAssignStmt(AssignStatement update, ResolutionContext resolutionContext,
       int errorCountBeforeCheckingStmt) {
       Contract.Requires(update != null);
       Contract.Requires(resolutionContext != null);
@@ -656,7 +656,7 @@ private void ResolveUpdateStmt(AssignStatement update, ResolutionContext resolut
         } else if (ErrorCount == errorCountBeforeCheckingStmt) {
           // add the statements here in a sequence, but don't use that sequence later for translation (instead, should translate properly as multi-assignment)
           for (var i = 0; i < update.Lhss.Count; i++) {
-            var a = new SingleAssignStmt(update.RangeToken, update.Lhss[i].Resolved, update.Rhss[i]);
+            var a = new SingleAssignStmt(update.Origin, update.Lhss[i].Resolved, update.Rhss[i]);
             update.ResolvedStatements.Add(a);
           }
         }
@@ -676,7 +676,7 @@ private void ResolveUpdateStmt(AssignStatement update, ResolutionContext resolut
             if (tr.CanAffectPreviouslyKnownExpressions) {
               ReportError(tr.Tok, "can only have initialization methods which modify at most 'this'.");
             } else if (ErrorCount == errorCountBeforeCheckingStmt) {
-              var a = new SingleAssignStmt(update.RangeToken, update.Lhss[0].Resolved, tr);
+              var a = new SingleAssignStmt(update.Origin, update.Lhss[0].Resolved, tr);
               update.ResolvedStatements.Add(a);
             }
           }
@@ -697,13 +697,13 @@ private void ResolveUpdateStmt(AssignStatement update, ResolutionContext resolut
               "the number of left-hand sides ({0}) and right-hand sides ({1}) must match for a multi-assignment",
               update.Lhss.Count, update.Rhss.Count);
           } else if (ErrorCount == errorCountBeforeCheckingStmt) {
-            var a = new SingleAssignStmt(update.RangeToken, update.Lhss[0].Resolved, update.Rhss[0]);
+            var a = new SingleAssignStmt(update.Origin, update.Lhss[0].Resolved, update.Rhss[0]);
             update.ResolvedStatements.Add(a);
           }
         } else if (ErrorCount == errorCountBeforeCheckingStmt) {
           // a call statement
           var resolvedLhss = update.Lhss.ConvertAll(ll => ll.Resolved);
-          var a = new CallStmt(update.RangeToken, resolvedLhss, methodCallInfo.Callee, methodCallInfo.ActualParameters, methodCallInfo.Tok);
+          var a = new CallStmt(update.Origin, resolvedLhss, methodCallInfo.Callee, methodCallInfo.ActualParameters, methodCallInfo.Tok);
           a.OriginalInitialLhs = update.OriginalInitialLhs;
           update.ResolvedStatements.Add(a);
         }
@@ -768,7 +768,7 @@ void ResolveCallStmt(CallStmt s, ResolutionContext resolutionContext, Type recei
       bool tryToResolve = false;
       if (callee.Outs.Count != s.Lhs.Count) {
         if (isInitCall) {
-          ReportError(s, "a method called as an initialization method must not have any result arguments");
+          ReportError(s.MethodSelect.Origin, "a method called as an initialization method must not have any result arguments");
         } else {
           ReportError(s, "wrong number of method result arguments (got {0}, expected {1})", s.Lhs.Count, callee.Outs.Count);
           tryToResolve = true;
@@ -971,9 +971,9 @@ private void ResolveAssignOrReturnStmt(AssignOrReturnStmt s, ResolutionContext r
         }
       }
       var temp = resolver.FreshTempVarName("valueOrError", resolutionContext.CodeContext);
-      var lhss = new List<LocalVariable>() { new LocalVariable(s.RangeToken, temp, new InferredTypeProxy(), false) };
+      var lhss = new List<LocalVariable>() { new LocalVariable(s.Origin, temp, new InferredTypeProxy(), false) };
       // "var temp ;"
-      s.ResolvedStatements.Add(new VarDeclStmt(s.RangeToken, lhss, null));
+      s.ResolvedStatements.Add(new VarDeclStmt(s.Origin, lhss, null));
       var lhss2 = new List<Expression>() { new IdentifierExpr(s.Tok, temp) };
       for (int k = (expectExtract ? 1 : 0); k < s.Lhss.Count; ++k) {
         lhss2.Add(s.Lhss[k]);
@@ -991,7 +991,7 @@ private void ResolveAssignOrReturnStmt(AssignOrReturnStmt s, ResolutionContext r
         }
       }
       // " temp, ... := MethodOrExpression, ...;"
-      var up = new AssignStatement(s.RangeToken, lhss2, rhss2);
+      var up = new AssignStatement(s.Origin, lhss2, rhss2);
       if (expectExtract) {
         up.OriginalInitialLhs = s.Lhss.Count == 0 ? null : s.Lhss[0];
       }
@@ -1023,14 +1023,14 @@ private void ResolveAssignOrReturnStmt(AssignOrReturnStmt s, ResolutionContext r
 
         s.ResolvedStatements.Add(
           // "if temp.IsFailure()"
-          new IfStmt(s.RangeToken, false, resolver.VarDotMethod(s.Tok, temp, "IsFailure"),
+          new IfStmt(s.Origin, false, resolver.VarDotMethod(s.Tok, temp, "IsFailure"),
             // THEN: { out := temp.PropagateFailure(); return; }
-            new BlockStmt(s.RangeToken, new List<Statement>() {
-              new AssignStatement(s.RangeToken,
+            new BlockStmt(s.Origin, new List<Statement>() {
+              new AssignStatement(s.Origin,
                 new List<Expression>() { ident },
                 new List<AssignmentRhs>() {new ExprRhs(resolver.VarDotMethod(s.Tok, temp, "PropagateFailure"))}
               ),
-              new ReturnStmt(s.RangeToken, null),
+              new ReturnStmt(s.Origin, null),
             }),
             // ELSE: no else block
             null
@@ -1041,7 +1041,7 @@ private void ResolveAssignOrReturnStmt(AssignOrReturnStmt s, ResolutionContext r
         // "y := temp.Extract();"
         var lhs = s.Lhss[0];
         s.ResolvedStatements.Add(
-          new AssignStatement(s.RangeToken,
+          new AssignStatement(s.Origin,
             new List<Expression>() { lhsExtract },
             new List<AssignmentRhs>() { new ExprRhs(resolver.VarDotMethod(s.Tok, temp, "Extract")) }
           ));
@@ -1199,7 +1199,7 @@ public void ResolveTypeRhs(TypeRhs rr, Statement stmt, ResolutionContext resolut
               Contract.Assert(callLhs.ResolvedExpression is MemberSelectExpr);  // since ResolveApplySuffix succeeded and call.Lhs denotes an expression (not a module or a type)
               var methodSel = (MemberSelectExpr)callLhs.ResolvedExpression;
               if (methodSel.Member is Method) {
-                rr.InitCall = new CallStmt(stmt.RangeToken, new List<Expression>(), methodSel, rr.Bindings.ArgumentBindings, initCallTok);
+                rr.InitCall = new CallStmt(stmt.Origin, new List<Expression>(), methodSel, rr.Bindings.ArgumentBindings, initCallTok);
                 ResolveCallStmt(rr.InitCall, resolutionContext, rr.EType);
               } else {
                 ReportError(initCallTok, "object initialization must denote an initializing method or constructor ({0})", initCallName);
diff --git a/Source/DafnyCore/Resolver/PreType/UnderspecificationDetector.cs b/Source/DafnyCore/Resolver/PreType/UnderspecificationDetector.cs
index b5b840f8859..e1f1ef91252 100644
--- a/Source/DafnyCore/Resolver/PreType/UnderspecificationDetector.cs
+++ b/Source/DafnyCore/Resolver/PreType/UnderspecificationDetector.cs
@@ -84,11 +84,11 @@ public void Check(List<TopLevelDecl> declarations) {
               for (int i = 1; i < dtor.CorrespondingFormals.Count; i++) {
                 var other = dtor.CorrespondingFormals[i];
                 if (!Type.Equal_Improved(rolemodel.Type, other.Type)) {
-                  ReportError(other.tok,
+                  ReportError(other.Origin,
                     "shared destructors must have the same type, but '{0}' has type '{1}' in constructor '{2}' and type '{3}' in constructor '{4}'",
                     rolemodel.Name, rolemodel.Type, dtor.EnclosingCtors[0].Name, other.Type, dtor.EnclosingCtors[i].Name);
                 } else if (rolemodel.IsGhost != other.IsGhost) {
-                  ReportError(other.tok,
+                  ReportError(other.Origin,
                     "shared destructors must agree on whether or not they are ghost, but '{0}' is {1} in constructor '{2}' and {3} in constructor '{4}'",
                     rolemodel.Name,
                     rolemodel.IsGhost ? "ghost" : "non-ghost", dtor.EnclosingCtors[0].Name,
diff --git a/Source/DafnyCore/Rewriters/AutoContractsRewriter.cs b/Source/DafnyCore/Rewriters/AutoContractsRewriter.cs
index 6aae579aaae..c4f87529182 100644
--- a/Source/DafnyCore/Rewriters/AutoContractsRewriter.cs
+++ b/Source/DafnyCore/Rewriters/AutoContractsRewriter.cs
@@ -75,7 +75,7 @@ internal override void PreResolve(ModuleDefinition m) {
   }
 
   void ProcessClassPreResolve(TopLevelDeclWithMembers cl) {
-    var range = cl.NameNode.RangeToken.MakeAutoGenerated();
+    var range = cl.NameNode.Origin.MakeAutoGenerated();
     // Add:  ghost var Repr: set<object>
     // ...unless a field with that name is already present
     if (!cl.Members.Exists(member => member is Field && member.Name == "Repr")) {
@@ -87,7 +87,7 @@ void ProcessClassPreResolve(TopLevelDeclWithMembers cl) {
     // Add:  predicate Valid()
     // ...unless an instance function with that name is already present
     if (!cl.Members.Exists(member => member is Function && member.Name == "Valid" && !member.IsStatic)) {
-      var valid = new Predicate(range, new Name(cl.NameNode.RangeToken, "Valid"), false, true, false, new List<TypeParameter>(), new List<Formal>(), null,
+      var valid = new Predicate(range, new Name(cl.NameNode.Origin, "Valid"), false, true, false, new List<TypeParameter>(), new List<Formal>(), null,
         new List<AttributedExpression>(), new Specification<FrameExpression>(), new List<AttributedExpression>(), new Specification<Expression>(new List<Expression>(), null),
         null, Predicate.BodyOriginKind.OriginalOrInherited, null, null, null, null);
       cl.Members.Add(valid);
@@ -118,7 +118,7 @@ void ProcessClassPreResolve(TopLevelDeclWithMembers cl) {
           new BinaryExpr(tok, BinaryExpr.Opcode.In,
             new ThisExpr(tok),
             CreateUnresolvedThisRepr(tok)));
-        valid.Ens.Insert(0, new AttributedExpression(post));
+        valid.Ens.Insert(0, new AttributedExpression(tok, post));
         if (member.tok == cl.tok) {
           // We added this function above, so produce a hover text for the entire function signature
           AddHoverText(cl.tok, "{0}", Printer.FunctionSignatureToString(Reporter.Options, valid));
@@ -129,7 +129,7 @@ void ProcessClassPreResolve(TopLevelDeclWithMembers cl) {
         var f = (Function)member;
         // requires Valid()
         var valid = CreateUnresolvedValidCall(tok);
-        f.Req.Insert(0, new AttributedExpression(valid));
+        f.Req.Insert(0, new AttributedExpression(tok, valid));
         var format = "requires {0}";
         var repr = CreateUnresolvedThisRepr(tok);
         if (f.Reads.Expressions.Count == 0) {
@@ -142,10 +142,10 @@ void ProcessClassPreResolve(TopLevelDeclWithMembers cl) {
         var ctor = (Constructor)member;
         // ensures Valid();
         var valid = CreateUnresolvedValidCall(tok);
-        ctor.Ens.Insert(0, new AttributedExpression(valid));
+        ctor.Ens.Insert(0, new AttributedExpression(tok, valid));
         // ensures fresh(Repr);
         var freshness = new FreshExpr(tok, CreateUnresolvedThisRepr(tok));
-        ctor.Ens.Insert(1, new AttributedExpression(freshness));
+        ctor.Ens.Insert(1, new AttributedExpression(tok, freshness));
         var m0 = new ThisExpr(tok);
         AddHoverText(member.tok, "modifies {0}\nensures {1} && {2}", m0, valid, freshness);
       }
@@ -284,11 +284,11 @@ void ProcessClassPostResolve(ClassLikeDecl cl) {
             // Repr := {this};
             var e = new SetDisplayExpr(tok, true, new List<Expression>() { self });
             e.Type = systemModuleManager.ObjectSetType();
-            Statement s = new SingleAssignStmt(member.RangeToken, Repr, new ExprRhs(e));
+            Statement s = new SingleAssignStmt(member.Origin, Repr, new ExprRhs(e));
             s.IsGhost = true;
             sbs.AppendStmt(s);
           }
-          AddSubobjectReprs(tok, ctor.RangeToken.EndToken, subobjects, sbs, n, implicitSelf, Repr);
+          AddSubobjectReprs(tok, ctor.Origin.EndToken, subobjects, sbs, n, implicitSelf, Repr);
         }
 
       } else if (member is Method && !member.IsStatic && Valid != null) {
@@ -303,13 +303,13 @@ void ProcessClassPostResolve(ClassLikeDecl cl) {
               valid = new OldExpr(tok, valid);
               valid.Type = Type.Bool;
             }
-            m.Req.Insert(0, new AttributedExpression(valid));
+            m.Req.Insert(0, new AttributedExpression(tok, valid));
             AddHoverText(member.tok, "requires {0}", valid);
           }
         } else if (m.RefinementBase == null) {
           // requires Valid()
           var valid = CreateResolvedValidCall(tok, implicitSelf, Valid, m);
-          m.Req.Insert(0, new AttributedExpression(valid));
+          m.Req.Insert(0, new AttributedExpression(tok, valid));
           var format = "requires {0}";
           if (m.Mod.Expressions.Count == 0) {
             // modifies Repr
@@ -318,7 +318,7 @@ void ProcessClassPostResolve(ClassLikeDecl cl) {
             addStatementsToUpdateRepr = true;
           }
           // ensures Valid()
-          m.Ens.Insert(0, new AttributedExpression(valid));
+          m.Ens.Insert(0, new AttributedExpression(tok, valid));
           // ensures fresh(Repr - old(Repr));
           var e0 = new OldExpr(tok, Repr);
           e0.Type = Repr.Type;
@@ -327,7 +327,7 @@ void ProcessClassPostResolve(ClassLikeDecl cl) {
           e1.Type = Repr.Type;
           var freshness = new FreshExpr(tok, e1);
           freshness.Type = Type.Bool;
-          m.Ens.Insert(1, new AttributedExpression(freshness));
+          m.Ens.Insert(1, new AttributedExpression(tok, freshness));
           AddHoverText(m.tok, format + "\nensures {0} && {2}", valid, Repr, freshness);
         } else {
           addStatementsToUpdateRepr = true;
@@ -335,7 +335,7 @@ void ProcessClassPostResolve(ClassLikeDecl cl) {
 
         if (addStatementsToUpdateRepr && m.Body != null) {
           var methodBody = (BlockStmt)m.Body;
-          AddSubobjectReprs(tok, methodBody.RangeToken.EndToken, subobjects, methodBody, methodBody.Body.Count, implicitSelf, Repr);
+          AddSubobjectReprs(tok, methodBody.Origin.EndToken, subobjects, methodBody, methodBody.Body.Count, implicitSelf, Repr);
         }
       }
     }
@@ -375,13 +375,13 @@ void AddSubobjectReprs(IOrigin tok, IOrigin endCurlyTok, List<Tuple<Field, Field
         nguard = Expression.CreateAnd(nguard, ng);
       }
       // Repr := Repr + ...;
-      Statement s = new SingleAssignStmt(tok.ToRange(), Repr, new ExprRhs(rhs));
+      Statement s = new SingleAssignStmt(tok, Repr, new ExprRhs(rhs));
       s.IsGhost = true;
       // wrap if statement around s
       e = Expression.CreateAnd(IsNotNull(tok, F), Expression.CreateNot(tok, nguard));
-      var thn = new BlockStmt(tok.ToRange(), new List<Statement>() { s });
+      var thn = new BlockStmt(tok, new List<Statement>() { s });
       thn.IsGhost = true;
-      s = new IfStmt(tok.ToRange(), false, e, thn, null);
+      s = new IfStmt(tok, false, e, thn, null);
       s.IsGhost = true;
       // finally, add s to the block
       block.AppendStmt(s);
@@ -464,7 +464,7 @@ private static Expression CreateUnresolvedThisRepr(IOrigin tok) {
   public static Expression CreateUnresolvedValidCall(IOrigin tok) {
     return new ApplySuffix(tok, null,
       new ExprDotName(tok, new ImplicitThisExpr(tok), "Valid", null),
-      new List<ActualBinding>(), tok);
+      new List<ActualBinding>(), Token.NoToken);
   }
 
   /// <summary>
diff --git a/Source/DafnyCore/Rewriters/AutoGeneratedToken.cs b/Source/DafnyCore/Rewriters/AutoGeneratedOrigin.cs
similarity index 71%
rename from Source/DafnyCore/Rewriters/AutoGeneratedToken.cs
rename to Source/DafnyCore/Rewriters/AutoGeneratedOrigin.cs
index 085aa76026d..bcfb1a7993c 100644
--- a/Source/DafnyCore/Rewriters/AutoGeneratedToken.cs
+++ b/Source/DafnyCore/Rewriters/AutoGeneratedOrigin.cs
@@ -3,14 +3,14 @@
 namespace Microsoft.Dafny;
 
 public class AutoGeneratedOrigin : OriginWrapper {
-  public AutoGeneratedOrigin(IOrigin wrappedToken)
-    : base(wrappedToken) {
-    Contract.Requires(wrappedToken != null);
+  public AutoGeneratedOrigin(IOrigin wrappedOrigin)
+    : base(wrappedOrigin) {
+    Contract.Requires(wrappedOrigin != null);
   }
 
   public static IOrigin Unwrap(IOrigin token) {
     if (token is AutoGeneratedOrigin autoGeneratedToken) {
-      return Unwrap(autoGeneratedToken.WrappedToken);
+      return Unwrap(autoGeneratedToken.WrappedOrigin);
     }
 
     return token;
@@ -21,7 +21,7 @@ public static bool Is(IOrigin tok) {
       if (w is AutoGeneratedOrigin) {
         return true;
       }
-      tok = w.WrappedToken;
+      tok = w.WrappedOrigin;
     }
     return false;
   }
@@ -31,7 +31,7 @@ public static Expression WrapExpression(Expression expr) {
   }
 
   public override IOrigin WithVal(string newVal) {
-    return new AutoGeneratedOrigin(WrappedToken.WithVal(newVal));
+    return new AutoGeneratedOrigin(WrappedOrigin.WithVal(newVal));
   }
 
   public override bool IsCopy => true;
diff --git a/Source/DafnyCore/Rewriters/AutoReqFunctionRewriter.cs b/Source/DafnyCore/Rewriters/AutoReqFunctionRewriter.cs
index 4722529552f..3698e858ab5 100644
--- a/Source/DafnyCore/Rewriters/AutoReqFunctionRewriter.cs
+++ b/Source/DafnyCore/Rewriters/AutoReqFunctionRewriter.cs
@@ -130,7 +130,8 @@ Expression Andify(IOrigin tok, List<Expression> exprs) {
   }
 
   static AttributedExpression CreateAutoAttributedExpression(Expression e, Attributes attrs = null) {
-    return new AttributedExpression(AutoGeneratedOrigin.WrapExpression(e), attrs);
+    var wrapped = AutoGeneratedOrigin.WrapExpression(e);
+    return new AttributedExpression(wrapped.Origin, wrapped, attrs);
   }
 
   List<Expression> gatherReqs(Function f, List<Expression> args, List<Type> typeArguments, Expression f_this) {
@@ -344,7 +345,7 @@ List<Expression> GenerateAutoReqs(Expression expr) {
       //reqs.AddRange(generateAutoReqs(e.Range));
       var auto_reqs = GenerateAutoReqs(e.Term);
       if (auto_reqs.Count > 0) {
-        reqs.Add(Expression.CreateQuantifier(new ForallExpr(e.tok, e.RangeToken, e.BoundVars, e.Range, Andify(e.Term.tok, auto_reqs), e.Attributes), true));
+        reqs.Add(Expression.CreateQuantifier(new ForallExpr(e.tok, e.Origin, e.BoundVars, e.Range, Andify(e.Term.tok, auto_reqs), e.Attributes), true));
       }
     } else if (expr is MapComprehension) {
       var e = (MapComprehension)expr;
@@ -357,7 +358,7 @@ List<Expression> GenerateAutoReqs(Expression expr) {
       }
       auto_reqs.AddRange(GenerateAutoReqs(e.Term));
       if (auto_reqs.Count > 0) {
-        reqs.Add(Expression.CreateQuantifier(new ForallExpr(e.tok, e.RangeToken, e.BoundVars, e.Range, Andify(e.Term.tok, auto_reqs), e.Attributes), true));
+        reqs.Add(Expression.CreateQuantifier(new ForallExpr(e.tok, e.Origin, e.BoundVars, e.Range, Andify(e.Term.tok, auto_reqs), e.Attributes), true));
       }
     } else if (expr is StmtExpr) {
       var e = (StmtExpr)expr;
diff --git a/Source/DafnyCore/Rewriters/AutoRevealFunctionDependencies.cs b/Source/DafnyCore/Rewriters/AutoRevealFunctionDependencies.cs
index 3bd9b22c5c8..3c6e34cf05d 100644
--- a/Source/DafnyCore/Rewriters/AutoRevealFunctionDependencies.cs
+++ b/Source/DafnyCore/Rewriters/AutoRevealFunctionDependencies.cs
@@ -332,7 +332,7 @@ public static HideRevealStmt BuildRevealStmt(Function func, IOrigin tok, ModuleD
     rr.TypeApplicationJustMember = new List<Type>();
     rr.TypeApplicationAtEnclosingClass = args;
 
-    var call = new CallStmt(func.RangeToken, new List<Expression>(), rr, new List<ActualBinding>(),
+    var call = new CallStmt(func.Origin, new List<Expression>(), rr, new List<ActualBinding>(),
       func.Tok);
     call.IsGhost = true;
     call.Bindings.AcceptArgumentExpressionsAsExactParameterList(new List<Expression>());
@@ -343,10 +343,10 @@ public static HideRevealStmt BuildRevealStmt(Function func, IOrigin tok, ModuleD
     List<Expression> expressionList = new List<Expression> {
       new ApplySuffix(tok, null,
         resolveExpr,
-        new List<ActualBinding>(), tok)
+        new List<ActualBinding>(), Token.NoToken)
     };
 
-    var revealStmt = new HideRevealStmt(func.RangeToken, expressionList, HideRevealCmd.Modes.Reveal);
+    var revealStmt = new HideRevealStmt(func.Origin, expressionList, HideRevealCmd.Modes.Reveal);
     revealStmt.ResolvedStatements.Add(call);
     revealStmt.IsGhost = true;
 
diff --git a/Source/DafnyCore/Rewriters/ExpectContracts.cs b/Source/DafnyCore/Rewriters/ExpectContracts.cs
index 4a091da989c..acefc57fbd6 100644
--- a/Source/DafnyCore/Rewriters/ExpectContracts.cs
+++ b/Source/DafnyCore/Rewriters/ExpectContracts.cs
@@ -47,7 +47,7 @@ private Statement CreateContractExpectStatement(AttributedExpression expr, strin
       msg += " (not compiled because it references ghost state)";
     }
     var msgExpr = Expression.CreateStringLiteral(tok, msg);
-    return new ExpectStmt(expr.E.RangeToken, exprToCheck, msgExpr, null);
+    return new ExpectStmt(expr.E.Origin, exprToCheck, msgExpr, null);
   }
 
   /// <summary>
@@ -67,7 +67,7 @@ private BlockStmt MakeContractCheckingBody(IEnumerable<AttributedExpression> req
       CreateContractExpectStatement(ens, "ensures"));
     var callStmtList = new List<Statement>() { callStmt };
     var bodyStatements = expectRequiresStmts.Concat(callStmtList).Concat(expectEnsuresStmts);
-    return new BlockStmt(callStmt.RangeToken, bodyStatements.ToList());
+    return new BlockStmt(callStmt.Origin, bodyStatements.ToList());
   }
 
   private bool ShouldGenerateWrapper(MemberDecl decl) {
@@ -119,14 +119,7 @@ private MemberDecl GenerateFunctionWrapper(TopLevelDeclWithMembers parent, Membe
 
     var resultVar = origFunc.Result ?? new Formal(tok, "#result", newFunc.ResultType, false, false, null);
     var localExpr = Expression.CreateIdentExpr(resultVar);
-
-    var callRhs = new ExprRhs(callExpr);
-
-    var lhss = new List<Expression> { localExpr };
-    var rhss = new List<AssignmentRhs> { callRhs };
-
-    var callStmt = new SingleAssignStmt(decl.RangeToken, localExpr, callRhs);
-
+    var callStmt = new SingleAssignStmt(decl.Origin, localExpr, new ExprRhs(callExpr));
     var body = MakeContractCheckingBody(origFunc.Req, origFunc.Ens, callStmt);
 
     newFunc.ByMethodBody = body;
@@ -151,7 +144,7 @@ private MemberDecl GenerateMethodWrapper(TopLevelDeclWithMembers parent, MemberD
       newMethod.TypeArgs.Select(tp => (Type)new UserDefinedType(tp)).ToList();
     memberSelectExpr.TypeApplicationAtEnclosingClass =
       parent.TypeArgs.Select(tp => (Type)new UserDefinedType(tp)).ToList();
-    var callStmt = new CallStmt(decl.RangeToken, outs, memberSelectExpr, args);
+    var callStmt = new CallStmt(decl.Origin, outs, memberSelectExpr, args);
 
     var body = MakeContractCheckingBody(origMethod.Req, origMethod.Ens, callStmt);
     newMethod.Body = body;
@@ -172,7 +165,7 @@ private void RegisterResolvedByMethod(Formal resultVar, Function f, TopLevelDecl
     };
     var fn = Expression.CreateResolvedCall(tok, receiver, f, f.Ins.ConvertAll(Expression.CreateIdentExpr),
       f.TypeArgs.ConvertAll(typeParameter => (Type)new UserDefinedType(f.tok, typeParameter)), systemModuleManager);
-    var post = new AttributedExpression(new BinaryExpr(tok, BinaryExpr.Opcode.Eq, r, fn) {
+    var post = new AttributedExpression(tok, new BinaryExpr(tok, BinaryExpr.Opcode.Eq, r, fn) {
       Type = Type.Bool
     });
     // If f.Reads is empty, replace it with an explicit `reads {}` so that we don't replace that
@@ -183,7 +176,7 @@ private void RegisterResolvedByMethod(Formal resultVar, Function f, TopLevelDecl
       var emptySet = new SetDisplayExpr(tok, true, new List<Expression>());
       reads.Expressions.Add(new FrameExpression(tok, emptySet, null));
     }
-    var method = new Method(f.RangeToken, f.NameNode, f.HasStaticKeyword, false, f.TypeArgs,
+    var method = new Method(f.Origin, f.NameNode, f.HasStaticKeyword, false, f.TypeArgs,
       f.Ins, new List<Formal>() { resultVar },
       f.Req, reads, new Specification<FrameExpression>(new List<FrameExpression>(), null), new List<AttributedExpression>() { post }, f.Decreases,
       f.ByMethodBody, f.Attributes, null, true);
diff --git a/Source/DafnyCore/Rewriters/ForallStmtRewriter.cs b/Source/DafnyCore/Rewriters/ForallStmtRewriter.cs
index 7c36e63c71f..939c385a6fa 100644
--- a/Source/DafnyCore/Rewriters/ForallStmtRewriter.cs
+++ b/Source/DafnyCore/Rewriters/ForallStmtRewriter.cs
@@ -77,7 +77,7 @@ private static void VisitCall(ForallStmt s) {
           substituter.Substitute(s0.Method.Ens[i].E));
       }
 
-      var expr = new ForallExpr(new AutoGeneratedOrigin(s.Tok), s.RangeToken, s.BoundVars, s.Range, term, s.Attributes) {
+      var expr = new ForallExpr(new AutoGeneratedOrigin(s.Tok), s.Origin, s.BoundVars, s.Range, term, s.Attributes) {
         Type = Type.Bool, // resolve here
         Bounds = s.Bounds
       };
@@ -169,7 +169,7 @@ private void VisitAssign(ForallStmt stmt) {
               Printer.ExprToString(reporter.Options, newRhs));
             reporter.Info(MessageSource.Resolver, stmt.Tok, msg);
 
-            var expr = new ForallExpr(stmt.Tok, stmt.RangeToken, jList, val.Range,
+            var expr = new ForallExpr(stmt.Tok, stmt.Origin, jList, val.Range,
               new BinaryExpr(s0.Tok, BinaryExpr.ResolvedOpcode.EqCommon, lhs, newRhs),
               attributes) {
               Type = Type.Bool,
@@ -183,7 +183,7 @@ private void VisitAssign(ForallStmt stmt) {
       }
 
       if (!usedInversion) {
-        var expr = new ForallExpr(stmt.Tok, stmt.RangeToken, stmt.BoundVars, stmt.Range,
+        var expr = new ForallExpr(stmt.Tok, stmt.Origin, stmt.BoundVars, stmt.Range,
           new BinaryExpr(s0.Tok, BinaryExpr.ResolvedOpcode.EqCommon, lhs, rhs),
           stmt.Attributes) {
           Type = Type.Bool,
@@ -202,7 +202,7 @@ private static void VisitProof(ForallStmt s) {
       }
 
       s.EffectiveEnsuresClauses = new List<Expression> {
-        new ForallExpr(s.Tok, s.RangeToken, s.BoundVars, s.Range, term, s.Attributes) {
+        new ForallExpr(s.Tok, s.Origin, s.BoundVars, s.Range, term, s.Attributes) {
           Type = Type.Bool, // resolve here
           Bounds = s.Bounds
         }
diff --git a/Source/DafnyCore/Rewriters/InductionRewriter.cs b/Source/DafnyCore/Rewriters/InductionRewriter.cs
index b2e25ff7c3b..b8deabc4bb8 100644
--- a/Source/DafnyCore/Rewriters/InductionRewriter.cs
+++ b/Source/DafnyCore/Rewriters/InductionRewriter.cs
@@ -275,7 +275,7 @@ List<List<Expression>> ComputeInductionTriggers(List<Expression> inductionVariab
     }
 
     var substituter = new Substituter(receiverReplacement, substMap, new Dictionary<TypeParameter, Type>());
-    var quantifier = new ForallExpr(body.tok, body.RangeToken, boundVars, null, substituter.Substitute(body), null) {
+    var quantifier = new ForallExpr(body.tok, body.Origin, boundVars, null, substituter.Substitute(body), null) {
       Type = Type.Bool
     };
 
diff --git a/Source/DafnyCore/Rewriters/OpaqueMemberRewriter.cs b/Source/DafnyCore/Rewriters/OpaqueMemberRewriter.cs
index eb814a37bcd..c6f3a9d6d44 100644
--- a/Source/DafnyCore/Rewriters/OpaqueMemberRewriter.cs
+++ b/Source/DafnyCore/Rewriters/OpaqueMemberRewriter.cs
@@ -82,7 +82,7 @@ protected void ProcessOpaqueClassMembers(TopLevelDeclWithMembers c) {
         // Nothing to do
       } else if (member is Function { Body: null }) {
         // Nothing to do
-      } else if (!RefinementOrigin.IsInherited(member.tok, c.EnclosingModuleDefinition)) {
+      } else if (!RefinementOrigin.IsInherited(member.Origin, c.EnclosingModuleDefinition)) {
         GenerateRevealLemma(member, newDecls);
       }
     }
@@ -142,17 +142,17 @@ private void GenerateRevealLemma(MemberDecl m, List<MemberDecl> newDecls) {
 
     var isStatic = true;
     if (m is ConstantField { Rhs: not null } c) {
-      ens.Add(new AttributedExpression(new BinaryExpr(c.tok, BinaryExpr.Opcode.Eq, new NameSegment(c.Tok, c.Name, null), c.Rhs)));
+      ens.Add(new AttributedExpression(c.Origin, new BinaryExpr(c.tok, BinaryExpr.Opcode.Eq, new NameSegment(c.Tok, c.Name, null), c.Rhs)));
       isStatic = m.HasStaticKeyword;
     }
     Method reveal;
     if (m is TwoStateFunction) {
-      reveal = new TwoStateLemma(m.RangeToken.MakeAutoGenerated(), m.NameNode.Prepend(HideRevealStmt.RevealLemmaPrefix), isStatic,
+      reveal = new TwoStateLemma(m.Origin.MakeAutoGenerated(), m.NameNode.Prepend(HideRevealStmt.RevealLemmaPrefix), isStatic,
         new List<TypeParameter>(), new List<Formal>(), new List<Formal>(), new List<AttributedExpression>(),
         new Specification<FrameExpression>(), new Specification<FrameExpression>(), ens,
         new Specification<Expression>(new List<Expression>(), null), null, lemma_attrs, null);
     } else {
-      reveal = new Lemma(m.RangeToken.MakeAutoGenerated(), m.NameNode.Prepend(HideRevealStmt.RevealLemmaPrefix), isStatic, new List<TypeParameter>(),
+      reveal = new Lemma(m.Origin.MakeAutoGenerated(), m.NameNode.Prepend(HideRevealStmt.RevealLemmaPrefix), isStatic, new List<TypeParameter>(),
         new List<Formal>(), new List<Formal>(), new List<AttributedExpression>(),
         new Specification<FrameExpression>(), new Specification<FrameExpression>(), ens,
         new Specification<Expression>(new List<Expression>(), null), null, lemma_attrs, null);
diff --git a/Source/DafnyCore/Rewriters/PrecedenceLinter.cs b/Source/DafnyCore/Rewriters/PrecedenceLinter.cs
index e298e48a284..a7d6199225a 100644
--- a/Source/DafnyCore/Rewriters/PrecedenceLinter.cs
+++ b/Source/DafnyCore/Rewriters/PrecedenceLinter.cs
@@ -81,7 +81,7 @@ public PrecedenceLinterVisitor(CompilationData compilation, ErrorReporter report
     /// Regarding the "st" parameter, see the comment above the class.
     /// </summary>
     protected override bool VisitOneExpr(Expression expr, ref LeftMargin st) {
-      if (AutoGeneratedOrigin.Is(expr.tok) || expr is DefaultValueExpression || expr.RangeToken == null) {
+      if (AutoGeneratedOrigin.Is(expr.tok) || expr is DefaultValueExpression || expr.Origin == null) {
         return false; // don't traverse further
       }
 
@@ -250,7 +250,7 @@ void VisitRhsComponent(IOrigin errorToken, Expression expr, int rightMargin, str
         Visit(expr, st);
         if (st.Column < rightMargin) {
           reporter.Warning(MessageSource.Rewriter, ErrorId.rw_unusual_indentation_end, errorToken,
-            $"unusual indentation in {what} (which ends at {LineCol(expr.RangeToken.EndToken)}); do you perhaps need parentheses?");
+            $"unusual indentation in {what} (which ends at {LineCol(expr.Origin.EndToken)}); do you perhaps need parentheses?");
         }
       }
     }
diff --git a/Source/DafnyCore/Rewriters/RefinementTransformer.cs b/Source/DafnyCore/Rewriters/RefinementTransformer.cs
index e695419228a..9469502be32 100644
--- a/Source/DafnyCore/Rewriters/RefinementTransformer.cs
+++ b/Source/DafnyCore/Rewriters/RefinementTransformer.cs
@@ -26,6 +26,9 @@ namespace Microsoft.Dafny {
   public class RefinementOrigin : OriginWrapper {
     public readonly ModuleDefinition InheritingModule;
 
+    public static bool IsInherited(IOrigin tok, ModuleDefinition m) { // TODO inline
+      return tok.IsInherited(m);
+    }
 
     public RefinementOrigin(IOrigin tok, ModuleDefinition m)
       : base(tok) {
@@ -35,39 +38,17 @@ public RefinementOrigin(IOrigin tok, ModuleDefinition m)
     }
 
     public override string ToString() {
-      return $"refinement of {WrappedToken} by {InheritingModule.Name}";
+      return $"refinement of {WrappedOrigin} by {InheritingModule.Name}";
     }
 
     public override IOrigin WithVal(string newVal) {
-      return new RefinementOrigin(WrappedToken.WithVal(newVal), InheritingModule);
+      return new RefinementOrigin(WrappedOrigin.WithVal(newVal), InheritingModule);
     }
 
+    public override bool IsInherited(ModuleDefinition d) => InheritingModule == d;
     public override bool IsCopy => true;
 
-    public static bool IsInherited(IOrigin tok, ModuleDefinition m) {
-      if (tok is AutoGeneratedOrigin agt) {
-        tok = agt.WrappedToken;
-      }
-      while (tok is NestedOrigin) {
-        var n = (NestedOrigin)tok;
-        // check Outer
-        var r = n.Outer as RefinementOrigin;
-        if (r == null || r.InheritingModule != m) {
-          return false;
-        }
-
-        // continue to check Inner
-        tok = n.Inner;
-        if (tok is AutoGeneratedOrigin nestedAtg) {
-          tok = nestedAtg.WrappedToken;
-        }
-      }
-
-      var rtok = tok as RefinementOrigin;
-      return rtok != null && rtok.InheritingModule == m;
-    }
-
-    public override string Filepath => WrappedToken.Filepath + "[" + InheritingModule.Name + "]";
+    public override string Filepath => WrappedOrigin.Filepath + "[" + InheritingModule.Name + "]";
   }
 
   /// <summary>
@@ -505,13 +486,13 @@ Function CloneFunction(Function newFunction, Function previousFunction, Expressi
       }
       var byMethodBody = refinementCloner.CloneBlockStmt(previousFunction.ByMethodBody);
 
-      var range = newFunction.RangeToken;
+      var range = newFunction.Origin;
       var nameNode = newFunction.NameNode;
 
       if (previousFunction is Predicate) {
         return new Predicate(range, nameNode, previousFunction.HasStaticKeyword, newFunction.IsGhost, previousFunction.IsOpaque, tps, formals, result,
           req, reads, ens, decreases, body, bodyOrigin,
-          previousFunction.ByMethodTok == null ? null : refinementCloner.Tok(previousFunction.ByMethodTok), byMethodBody,
+          previousFunction.ByMethodTok == null ? null : refinementCloner.Origin(previousFunction.ByMethodTok), byMethodBody,
           refinementCloner.MergeAttributes(previousFunction.Attributes, moreAttributes), null);
       } else if (previousFunction is LeastPredicate) {
         return new LeastPredicate(range, nameNode, previousFunction.HasStaticKeyword, previousFunction.IsOpaque, ((LeastPredicate)previousFunction).TypeOfK, tps, formals, result,
@@ -528,7 +509,7 @@ Function CloneFunction(Function newFunction, Function previousFunction, Expressi
       } else {
         return new Function(range, nameNode, previousFunction.HasStaticKeyword, newFunction.IsGhost, previousFunction.IsOpaque, tps, formals, result, refinementCloner.CloneType(previousFunction.ResultType),
           req, reads, ens, decreases, body,
-          previousFunction.ByMethodTok == null ? null : refinementCloner.Tok(previousFunction.ByMethodTok), byMethodBody,
+          previousFunction.ByMethodTok == null ? null : refinementCloner.Origin(previousFunction.ByMethodTok), byMethodBody,
           refinementCloner.MergeAttributes(previousFunction.Attributes, moreAttributes), null);
       }
     }
@@ -553,11 +534,11 @@ Method CloneMethod(Method previousMethod, List<AttributedExpression> moreEnsures
 
       if (previousMethod is Constructor) {
         var dividedBody = (DividedBlockStmt)newBody ?? refinementCloner.CloneDividedBlockStmt((DividedBlockStmt)previousMethod.Body);
-        return new Constructor(previousMethod.RangeToken.MakeRefined(moduleUnderConstruction), previousMethod.NameNode.Clone(refinementCloner), previousMethod.IsGhost, tps, ins,
+        return new Constructor(previousMethod.Origin.MakeRefined(moduleUnderConstruction), previousMethod.NameNode.Clone(refinementCloner), previousMethod.IsGhost, tps, ins,
           req, reads, mod, ens, decreases, dividedBody, refinementCloner.MergeAttributes(previousMethod.Attributes, moreAttributes), null);
       }
       var body = newBody ?? refinementCloner.CloneBlockStmt(previousMethod.Body);
-      var newRange = currentMethod.RangeToken.MakeRefined(moduleUnderConstruction);
+      var newRange = currentMethod.Origin.MakeRefined(moduleUnderConstruction);
       var newName = currentMethod.NameNode.Clone(refinementCloner);
       if (previousMethod is LeastLemma) {
         return new LeastLemma(newRange, newName, previousMethod.HasStaticKeyword, ((LeastLemma)previousMethod).TypeOfK, tps, ins,
@@ -631,7 +612,7 @@ IteratorDecl MergeIterator(IteratorDecl nw, IteratorDecl prev) {
         prev.YieldEnsures.ConvertAll(refinementCloner.CloneAttributedExpr));
       yens.AddRange(nw.YieldEnsures);
 
-      return new IteratorDecl(nw.RangeToken.MakeRefined(moduleUnderConstruction),
+      return new IteratorDecl(nw.Origin.MakeRefined(moduleUnderConstruction),
         nw.NameNode, moduleUnderConstruction,
         nw.SignatureIsOmitted ? prev.TypeArgs.ConvertAll(refinementCloner.CloneTypeParam) : nw.TypeArgs,
         nw.SignatureIsOmitted ? prev.Ins.ConvertAll(p => refinementCloner.CloneFormal(p, false)) : nw.Ins,
@@ -691,7 +672,7 @@ TopLevelDeclWithMembers MergeClass(TopLevelDeclWithMembers nw, TopLevelDeclWithM
               if ((!(origConst.Type is InferredTypeProxy) && newConst.Type is InferredTypeProxy) || (origConst.Rhs != null && newConst.Rhs == null)) {
                 var typ = newConst.Type is InferredTypeProxy ? refinementCloner.CloneType(origConst.Type) : newConst.Type;
                 var rhs = newConst.Rhs ?? origConst.Rhs;
-                nw.Members[index] = new ConstantField(newConst.RangeToken, newConst.NameNode, rhs, newConst.HasStaticKeyword, newConst.IsGhost, newConst.IsOpaque, typ, newConst.Attributes);
+                nw.Members[index] = new ConstantField(newConst.Origin, newConst.NameNode, rhs, newConst.HasStaticKeyword, newConst.IsGhost, newConst.IsOpaque, typ, newConst.Attributes);
               }
             }
 
@@ -760,8 +741,8 @@ TopLevelDeclWithMembers MergeClass(TopLevelDeclWithMembers nw, TopLevelDeclWithM
                 Error(ErrorId.ref_mismatched_refinement_body, nwMember, $"a refining {f.WhatKind} is not allowed to extend/change the body");
               }
               var newF = CloneFunction(f, prevFunction, moreBody, replacementBody, prevFunction.Body == null, f.Attributes);
-              newF.RangeToken = f.RangeToken;
-              newF.NameNode.RangeToken = f.NameNode.RangeToken;
+              newF.RangeOrigin = f.Origin;
+              newF.NameNode.RangeOrigin = f.NameNode.Origin;
               newF.RefinementBase = member;
               nw.Members[index] = newF;
             }
@@ -824,8 +805,8 @@ TopLevelDeclWithMembers MergeClass(TopLevelDeclWithMembers nw, TopLevelDeclWithM
                 }
               }
               var newM = CloneMethod(prevMethod, m.Ens, decreases, replacementBody, prevMethod.Body == null, m.Attributes);
-              newM.RangeToken = m.RangeToken;
-              newM.NameNode.RangeToken = m.NameNode.RangeToken;
+              newM.RangeOrigin = m.Origin;
+              newM.NameNode.RangeOrigin = m.NameNode.Origin;
               newM.RefinementBase = member;
               nw.Members[index] = newM;
             }
@@ -967,15 +948,15 @@ BlockStmt MergeBlockStmt(BlockStmt skeleton, BlockStmt oldStmt) {
         }
         var bodyProper = MergeStmtList(sbsSkeleton.BodyProper, sbsOldStmt.BodyProper, out hoverText);
         if (hoverText.Length != 0) {
-          Reporter.Info(MessageSource.RefinementTransformer, sbsSkeleton.RangeToken.ToToken(), hoverText);
+          Reporter.Info(MessageSource.RefinementTransformer, sbsSkeleton.Origin, hoverText);
         }
-        return new DividedBlockStmt(sbsSkeleton.RangeToken, bodyInit, sbsSkeleton.SeparatorTok, bodyProper);
+        return new DividedBlockStmt(sbsSkeleton.Origin, bodyInit, sbsSkeleton.SeparatorTok, bodyProper);
       } else {
         var body = MergeStmtList(skeleton.Body, oldStmt.Body, out var hoverText);
         if (hoverText.Length != 0) {
-          Reporter.Info(MessageSource.RefinementTransformer, skeleton.RangeToken.ToToken(), hoverText);
+          Reporter.Info(MessageSource.RefinementTransformer, skeleton.Origin, hoverText);
         }
-        return new BlockStmt(skeleton.RangeToken, body);
+        return new BlockStmt(skeleton.Origin, body);
       }
     }
 
@@ -1077,7 +1058,7 @@ List<Statement> MergeStmtList(List<Statement> skeleton, List<Statement> oldStmt,
                 // that the condition is inherited.
                 var e = refinementCloner.CloneExpr(oldAssume.Expr);
                 var attrs = refinementCloner.MergeAttributes(oldAssume.Attributes, skel.Attributes);
-                body.Add(new AssertStmt(new RangeToken(new BoogieGenerator.ForceCheckOrigin(skel.RangeToken.StartToken), skel.RangeToken.EndToken),
+                body.Add(new AssertStmt(new BoogieGenerator.ForceCheckOrigin(skel.Origin),
                   e, skel.Label, new Attributes("_prependAssertToken", new List<Expression>(), attrs)));
                 Reporter.Info(MessageSource.RefinementTransformer, c.ConditionEllipsis, "assume->assert: " + Printer.ExprToString(Reporter.Options, e));
                 i++; j++;
@@ -1094,7 +1075,7 @@ List<Statement> MergeStmtList(List<Statement> skeleton, List<Statement> oldStmt,
                 var e = refinementCloner.CloneExpr(oldExpect.Expr);
                 var message = refinementCloner.CloneExpr(oldExpect.Message);
                 var attrs = refinementCloner.MergeAttributes(oldExpect.Attributes, skel.Attributes);
-                body.Add(new ExpectStmt(skel.RangeToken, e, message, attrs));
+                body.Add(new ExpectStmt(skel.Origin, e, message, attrs));
                 Reporter.Info(MessageSource.RefinementTransformer, c.ConditionEllipsis, Printer.ExprToString(Reporter.Options, e));
                 i++; j++;
               }
@@ -1109,7 +1090,7 @@ List<Statement> MergeStmtList(List<Statement> skeleton, List<Statement> oldStmt,
               } else {
                 var e = refinementCloner.CloneExpr(oldAssume.Expr);
                 var attrs = refinementCloner.MergeAttributes(oldAssume.Attributes, skel.Attributes);
-                body.Add(new AssumeStmt(skel.RangeToken, e, attrs));
+                body.Add(new AssumeStmt(skel.Origin, e, attrs));
                 Reporter.Info(MessageSource.RefinementTransformer, c.ConditionEllipsis, Printer.ExprToString(Reporter.Options, e));
                 i++; j++;
               }
@@ -1125,7 +1106,7 @@ List<Statement> MergeStmtList(List<Statement> skeleton, List<Statement> oldStmt,
                 var resultingThen = MergeBlockStmt(skel.Thn, oldIf.Thn);
                 var resultingElse = MergeElse(skel.Els, oldIf.Els);
                 var e = refinementCloner.CloneExpr(oldIf.Guard);
-                var r = new IfStmt(skel.RangeToken, oldIf.IsBindingGuard, e, resultingThen, resultingElse);
+                var r = new IfStmt(skel.Origin, oldIf.IsBindingGuard, e, resultingThen, resultingElse);
                 body.Add(r);
                 Reporter.Info(MessageSource.RefinementTransformer, c.ConditionEllipsis, Printer.GuardToString(Reporter.Options, oldIf.IsBindingGuard, e));
                 i++; j++;
@@ -1171,14 +1152,14 @@ List<Statement> MergeStmtList(List<Statement> skeleton, List<Statement> oldStmt,
                   // Note, it is important to call MergeBlockStmt here (rather than just setting "mbody" to "skel.Body"), even
                   // though we're passing in an empty block as its second argument. The reason for this is that MergeBlockStmt
                   // also sets ".ReverifyPost" to "true" for any "return" statements.
-                  mbody = MergeBlockStmt(skel.Body, new BlockStmt(oldModifyStmt.RangeToken, new List<Statement>()));
+                  mbody = MergeBlockStmt(skel.Body, new BlockStmt(oldModifyStmt.Origin, new List<Statement>()));
                 } else if (skel.Body == null) {
                   Error(ErrorId.ref_mismatched_statement_body, cur.Tok, "modify template must have a body if the inherited modify statement does");
                   mbody = null;
                 } else {
                   mbody = MergeBlockStmt(skel.Body, oldModifyStmt.Body);
                 }
-                body.Add(new ModifyStmt(skel.RangeToken, mod.Expressions, mod.Attributes, mbody));
+                body.Add(new ModifyStmt(skel.Origin, mod.Expressions, mod.Attributes, mbody));
                 Reporter.Info(MessageSource.RefinementTransformer, c.ConditionEllipsis, Printer.FrameExprListToString(Reporter.Options, mod.Expressions));
                 i++; j++;
               }
@@ -1223,8 +1204,7 @@ List<Statement> MergeStmtList(List<Statement> skeleton, List<Statement> oldStmt,
               body.Add(cNew);
               i++; j++;
               if (addedAssert != null) {
-                var tok = new BoogieGenerator.ForceCheckOrigin(addedAssert.RangeToken.StartToken);
-                body.Add(new AssertStmt(new RangeToken(tok, addedAssert.RangeToken.EndToken), addedAssert, null, null));
+                body.Add(new AssertStmt(new BoogieGenerator.ForceCheckOrigin(addedAssert.Origin), addedAssert, null, null));
               }
             } else {
               MergeAddStatement(cur, body);
@@ -1280,7 +1260,7 @@ List<Statement> MergeStmtList(List<Statement> skeleton, List<Statement> oldStmt,
                 doMerge = true;
                 stmtGenerated.Add(nw);
                 var addedAssert = refinementCloner.CloneExpr(s.Expr);
-                var tok = new RangeToken(addedAssert.RangeToken.StartToken, addedAssert.RangeToken.EndToken);
+                var tok = new RangeToken(addedAssert.Origin.StartToken, addedAssert.Origin.EndToken);
                 stmtGenerated.Add(new AssertStmt(tok, addedAssert, null, null));
               }
             }
@@ -1297,7 +1277,7 @@ List<Statement> MergeStmtList(List<Statement> skeleton, List<Statement> oldStmt,
             var cNew = (IfStmt)cur;
             var cOld = oldS as IfStmt;
             if (cOld != null && cOld.Guard == null) {
-              var r = new IfStmt(cNew.RangeToken, cNew.IsBindingGuard, cNew.Guard, MergeBlockStmt(cNew.Thn, cOld.Thn), MergeElse(cNew.Els, cOld.Els));
+              var r = new IfStmt(cNew.Origin, cNew.IsBindingGuard, cNew.Guard, MergeBlockStmt(cNew.Thn, cOld.Thn), MergeElse(cNew.Els, cOld.Els));
               body.Add(r);
               i++; j++;
             } else {
@@ -1464,14 +1444,14 @@ WhileStmt MergeWhileStmt(WhileStmt cNew, WhileStmt cOld, Expression guard) {
       if (cOld.Body == null && cNew.Body == null) {
         newBody = null;
       } else if (cOld.Body == null) {
-        newBody = MergeBlockStmt(cNew.Body, new BlockStmt(cOld.RangeToken, new List<Statement>()));
+        newBody = MergeBlockStmt(cNew.Body, new BlockStmt(cOld.Origin, new List<Statement>()));
       } else if (cNew.Body == null) {
         Error(ErrorId.ref_mismatched_while_body, cNew.Tok, "while template must have a body if the inherited while statement does");
         newBody = null;
       } else {
         newBody = MergeBlockStmt(cNew.Body, cOld.Body);
       }
-      return new RefinedWhileStmt(cNew.RangeToken, guard, invs, decr, refinementCloner.CloneSpecFrameExpr(cOld.Mod), newBody);
+      return new RefinedWhileStmt(cNew.Origin, guard, invs, decr, refinementCloner.CloneSpecFrameExpr(cOld.Mod), newBody);
     }
 
     Statement MergeElse(Statement skeleton, Statement oldStmt) {
@@ -1482,15 +1462,15 @@ Statement MergeElse(Statement skeleton, Statement oldStmt) {
         return refinementCloner.CloneStmt(oldStmt, false);
       } else if (skeleton is IfStmt || skeleton is SkeletonStatement) {
         // wrap a block statement around the if statement
-        skeleton = new BlockStmt(skeleton.RangeToken, new List<Statement>() { skeleton });
+        skeleton = new BlockStmt(skeleton.Origin, new List<Statement>() { skeleton });
       }
 
       if (oldStmt == null) {
         // make it into an empty block statement
-        oldStmt = new BlockStmt(skeleton.RangeToken, new List<Statement>());
+        oldStmt = new BlockStmt(skeleton.Origin, new List<Statement>());
       } else if (oldStmt is IfStmt || oldStmt is SkeletonStatement) {
         // wrap a block statement around the if statement
-        oldStmt = new BlockStmt(skeleton.RangeToken, new List<Statement>() { oldStmt });
+        oldStmt = new BlockStmt(skeleton.Origin, new List<Statement>() { oldStmt });
       }
 
       Contract.Assert(skeleton is BlockStmt && oldStmt is BlockStmt);
@@ -1641,12 +1621,15 @@ public T WithRefinementTokenWrapping<T>(Func<T> action, bool wrap = false) {
       return result;
     }
 
-    public override IOrigin Tok(IOrigin tok) {
+    public override IOrigin Origin(IOrigin origin) {
+      if (origin == null) {
+        return null;
+      }
       if (wrapWithRefinementToken) {
-        return new RefinementOrigin(tok, moduleUnderConstruction);
+        return new RefinementOrigin(origin, moduleUnderConstruction);
       }
 
-      return tok;
+      return origin;
     }
     public override TopLevelDecl CloneDeclaration(TopLevelDecl d, ModuleDefinition newParent) {
       var dd = base.CloneDeclaration(d, newParent);
@@ -1655,7 +1638,7 @@ public override TopLevelDecl CloneDeclaration(TopLevelDecl d, ModuleDefinition n
         // refining module, retain its name but not be default, unless the refining module has the same name
         ModuleExportDecl dex = d as ModuleExportDecl;
         if (dex.IsDefault && d.Name != newParent.Name) {
-          ddex = new ModuleExportDecl(ddex.Options, dex.RangeToken, d.NameNode, newParent, dex.Exports, dex.Extends,
+          ddex = new ModuleExportDecl(ddex.Options, dex.Origin, d.NameNode, newParent, dex.Exports, dex.Extends,
             dex.ProvideAll, dex.RevealAll, false, true, Guid.NewGuid());
         }
         ddex.SetupDefaultSignature();
@@ -1673,15 +1656,15 @@ public virtual Attributes MergeAttributes(Attributes prevAttrs, Attributes moreA
         return CloneAttributes(prevAttrs);
       } else if (moreAttrs is UserSuppliedAttributes) {
         var usa = (UserSuppliedAttributes)moreAttrs;
-        return new UserSuppliedAttributes(Tok(usa.tok), Tok(usa.OpenBrace), Tok(usa.CloseBrace), moreAttrs.Args.ConvertAll(CloneExpr), MergeAttributes(prevAttrs, moreAttrs.Prev));
+        return new UserSuppliedAttributes(Origin(usa.tok), Origin(usa.OpenBrace), Origin(usa.CloseBrace), moreAttrs.Args.ConvertAll(CloneExpr), MergeAttributes(prevAttrs, moreAttrs.Prev));
       } else if (moreAttrs is UserSuppliedAtAttribute usaa) {
         var arg = CloneExpr(usaa.Arg);
         if (usaa.Arg.Type != null) { // The attribute has already been expanded
           arg.Type = usaa.Arg.Type;
           arg.PreType = usaa.Arg.PreType;
         }
-        return new UserSuppliedAtAttribute(Tok(usaa.tok), arg, MergeAttributes(prevAttrs, moreAttrs.Prev)) {
-          RangeToken = Tok(usaa.RangeToken),
+        return new UserSuppliedAtAttribute(Origin(usaa.tok), arg, MergeAttributes(prevAttrs, moreAttrs.Prev)) {
+          RangeOrigin = Origin(usaa.Origin),
           Builtin = usaa.Builtin
         };
       } else {
diff --git a/Source/DafnyCore/Rewriters/RunAllTestsMainMethod.cs b/Source/DafnyCore/Rewriters/RunAllTestsMainMethod.cs
index 11322217052..5f90097a400 100644
--- a/Source/DafnyCore/Rewriters/RunAllTestsMainMethod.cs
+++ b/Source/DafnyCore/Rewriters/RunAllTestsMainMethod.cs
@@ -178,15 +178,15 @@ internal override void PostResolve(Program program) {
               }
           }
 
-          var callStmt = new CallStmt(tok.ToRange(), lhss, methodSelectExpr, new List<Expression>());
+          var callStmt = new CallStmt(tok, lhss, methodSelectExpr, new List<Expression>());
           tryBodyStatements.Add(callStmt);
 
           Statement passedStmt = Statement.CreatePrintStmt(tok, Expression.CreateStringLiteral(tok, "PASSED\n"));
-          var passedBlock = new BlockStmt(tok.ToRange(), Util.Singleton(passedStmt));
+          var passedBlock = new BlockStmt(tok, Util.Singleton(passedStmt));
 
           if (resultVarExpr?.Type is UserDefinedType udt && udt.ResolvedClass is TopLevelDeclWithMembers resultClass) {
             var failureGuardExpr =
-              new FunctionCallExpr(tok, "IsFailure", resultVarExpr, tok, tok, new List<Expression>());
+              new FunctionCallExpr(tok, "IsFailure", resultVarExpr, Token.NoToken, Token.NoToken, new List<Expression>());
             var isFailureMember = resultClass.Members.First(m => m.Name == "IsFailure");
             failureGuardExpr.Function = (Function)isFailureMember;
             failureGuardExpr.Type = Type.Bool;
@@ -194,12 +194,12 @@ internal override void PostResolve(Program program) {
             failureGuardExpr.TypeApplication_AtEnclosingClass = new List<Type>();
 
             var failedBlock = PrintTestFailureStatement(tok, successVarExpr, resultVarExpr);
-            tryBodyStatements.Add(new IfStmt(tok.ToRange(), false, failureGuardExpr, failedBlock, passedBlock));
+            tryBodyStatements.Add(new IfStmt(tok, false, failureGuardExpr, failedBlock, passedBlock));
           } else { // Result is not a failure type
             tryBodyStatements.Add(passedBlock);
           }
 
-          var tryBody = new BlockStmt(tok.ToRange(), tryBodyStatements);
+          var tryBody = new BlockStmt(tok, tryBodyStatements);
 
           // Wrap the code above with:
           //
@@ -210,7 +210,7 @@ internal override void PostResolve(Program program) {
           //   success := false;
           // }
           //
-          var haltMessageVar = new LocalVariable(tok.ToRange(), "haltMessage", seqCharType, false) {
+          var haltMessageVar = new LocalVariable(tok, "haltMessage", seqCharType, false) {
             type = seqCharType
           };
           var haltMessageVarExpr = new IdentifierExpr(tok, haltMessageVar);
@@ -229,7 +229,7 @@ internal override void PostResolve(Program program) {
     //
     // expect success, "Test failures occurred: see above.\n";
     // 
-    Statement expectSuccess = new ExpectStmt(tok.ToRange(), successVarExpr,
+    Statement expectSuccess = new ExpectStmt(tok, successVarExpr,
       Expression.CreateStringLiteral(tok, "Test failures occurred: see above.\n"), null);
     mainMethodStatements.Add(expectSuccess);
 
@@ -237,16 +237,16 @@ internal override void PostResolve(Program program) {
     // than the Method we added in PreResolve).
     var hasMain = Compilers.SinglePassCodeGenerator.HasMain(program, out var mainMethod);
     Contract.Assert(hasMain);
-    mainMethod.Body = new BlockStmt(tok.ToRange(), mainMethodStatements);
+    mainMethod.Body = new BlockStmt(tok, mainMethodStatements);
   }
 
-  private BlockStmt PrintTestFailureStatement(IOrigin tok, Expression successVarExpr, Expression failureValueExpr) {
-    var failedPrintStmt = Statement.CreatePrintStmt(tok,
-      Expression.CreateStringLiteral(tok, "FAILED\n\t"),
+  private BlockStmt PrintTestFailureStatement(IOrigin origin, Expression successVarExpr, Expression failureValueExpr) {
+    var failedPrintStmt = Statement.CreatePrintStmt(origin,
+      Expression.CreateStringLiteral(origin, "FAILED\n\t"),
       failureValueExpr,
-      Expression.CreateStringLiteral(tok, "\n"));
+      Expression.CreateStringLiteral(origin, "\n"));
     var failSuiteStmt =
-      new SingleAssignStmt(tok.ToRange(), successVarExpr, new ExprRhs(Expression.CreateBoolLiteral(tok, false)));
-    return new BlockStmt(tok.ToRange(), Util.List<Statement>(failedPrintStmt, failSuiteStmt));
+      new SingleAssignStmt(origin, successVarExpr, new ExprRhs(Expression.CreateBoolLiteral(origin, false)));
+    return new BlockStmt(origin, Util.List<Statement>(failedPrintStmt, failSuiteStmt));
   }
 }
\ No newline at end of file
diff --git a/Source/DafnyCore/Snippets.cs b/Source/DafnyCore/Snippets.cs
index c5b0b9665f6..bfda0ef0163 100644
--- a/Source/DafnyCore/Snippets.cs
+++ b/Source/DafnyCore/Snippets.cs
@@ -18,23 +18,23 @@ static Snippets() {
     OptionRegistry.RegisterOption(ShowSnippets, OptionScope.Cli);
   }
 
-  public static void WriteSourceCodeSnippet(DafnyOptions options, IOrigin tok, TextWriter tw) {
-    string line = GetFileLine(options, tok.Uri, tok.line - 1);
+  public static void WriteSourceCodeSnippet(DafnyOptions options, IOrigin origin, TextWriter tw) {
+    string line = GetFileLine(options, origin.Uri, origin.line - 1);
     if (line == null) {
       return;
     }
 
-    string lineNumber = tok.line.ToString();
+    string lineNumber = origin.line.ToString();
     string lineNumberSpaces = new string(' ', lineNumber.Length);
-    string columnSpaces = new string(' ', tok.col - 1);
-    var lineStartPos = tok.pos - tok.col + 1;
+    string columnSpaces = new string(' ', origin.col - 1);
+    var lineStartPos = origin.pos - origin.col + 1;
     var lineEndPos = lineStartPos + line.Length;
 
-    var tokEndPos = tok.pos + tok.val.Length;
-    if (tok is RangeToken rangeToken) {
-      tokEndPos = rangeToken.EndToken.pos + rangeToken.EndToken.val.Length;
+    var endPosition = origin.pos + origin.val.Length;
+    if (origin.ContainsRange) {
+      endPosition = origin.EndToken.pos + origin.EndToken.val.Length;
     }
-    var underlineLength = Math.Max(1, Math.Min(tokEndPos - tok.pos, lineEndPos - tok.pos));
+    var underlineLength = Math.Max(1, Math.Min(endPosition - origin.pos, lineEndPos - origin.pos));
     string underline = new string('^', underlineLength);
     tw.WriteLine($"{lineNumberSpaces} |");
     tw.WriteLine($"{lineNumber} | {line}");
diff --git a/Source/DafnyCore/Triggers/ComprehensionTriggerGenerator.cs b/Source/DafnyCore/Triggers/ComprehensionTriggerGenerator.cs
index c8973c65064..045c3686105 100644
--- a/Source/DafnyCore/Triggers/ComprehensionTriggerGenerator.cs
+++ b/Source/DafnyCore/Triggers/ComprehensionTriggerGenerator.cs
@@ -184,11 +184,11 @@ private void CombineSplitQuantifier() {
           if (q.Comprehension is ForallExpr forallExpr) {
             IOrigin tok = forallExpr.tok is NestedOrigin nestedToken ? nestedToken.Outer : forallExpr.tok;
             Expression expr = QuantifiersToExpression(tok, BinaryExpr.ResolvedOpcode.And, group.Expressions);
-            q.Comprehension = new ForallExpr(tok, forallExpr.RangeToken, forallExpr.BoundVars, forallExpr.Range, expr, TriggerUtils.CopyAttributes(forallExpr.Attributes)) { Type = forallExpr.Type, Bounds = forallExpr.Bounds };
+            q.Comprehension = new ForallExpr(tok, forallExpr.Origin, forallExpr.BoundVars, forallExpr.Range, expr, TriggerUtils.CopyAttributes(forallExpr.Attributes)) { Type = forallExpr.Type, Bounds = forallExpr.Bounds };
           } else if (q.Comprehension is ExistsExpr existsExpr) {
             IOrigin tok = existsExpr.tok is NestedOrigin nestedToken ? nestedToken.Outer : existsExpr.tok;
             Expression expr = QuantifiersToExpression(tok, BinaryExpr.ResolvedOpcode.Or, group.Expressions);
-            q.Comprehension = new ExistsExpr(tok, existsExpr.RangeToken, existsExpr.BoundVars, existsExpr.Range, expr, TriggerUtils.CopyAttributes(existsExpr.Attributes)) { Type = existsExpr.Type, Bounds = existsExpr.Bounds };
+            q.Comprehension = new ExistsExpr(tok, existsExpr.Origin, existsExpr.BoundVars, existsExpr.Range, expr, TriggerUtils.CopyAttributes(existsExpr.Attributes)) { Type = existsExpr.Type, Bounds = existsExpr.Bounds };
           }
           list.Add(q);
           splits.Add(q.Comprehension);
diff --git a/Source/DafnyCore/Triggers/ExprSubstituter.cs b/Source/DafnyCore/Triggers/ExprSubstituter.cs
index 421bd233aaf..09855b3ad7f 100644
--- a/Source/DafnyCore/Triggers/ExprSubstituter.cs
+++ b/Source/DafnyCore/Triggers/ExprSubstituter.cs
@@ -62,10 +62,10 @@ public override Expression Substitute(Expression expr) {
 
         QuantifierExpr newExpr;
         if (expr is ForallExpr) {
-          newExpr = new ForallExpr(e.tok, e.RangeToken, newBoundVars, newRange, newTerm, newAttrs) { Bounds = newBounds };
+          newExpr = new ForallExpr(e.tok, e.Origin, newBoundVars, newRange, newTerm, newAttrs) { Bounds = newBounds };
         } else {
           Contract.Assert(expr is ExistsExpr);
-          newExpr = new ExistsExpr(e.tok, e.RangeToken, newBoundVars, newRange, newTerm, newAttrs) { Bounds = newBounds };
+          newExpr = new ExistsExpr(e.tok, e.Origin, newBoundVars, newRange, newTerm, newAttrs) { Bounds = newBounds };
         }
         usedSubstMap.Clear();
 
diff --git a/Source/DafnyCore/Triggers/QuantifierSplitter.cs b/Source/DafnyCore/Triggers/QuantifierSplitter.cs
index 2bfba373423..6a7c7995c92 100644
--- a/Source/DafnyCore/Triggers/QuantifierSplitter.cs
+++ b/Source/DafnyCore/Triggers/QuantifierSplitter.cs
@@ -83,7 +83,7 @@ private static IEnumerable<Expression> SplitQuantifier(ComprehensionExpr quantif
         }
         foreach (var e in stream) {
           var tok = new NestedOrigin(quantifier.tok, e.tok, "in subexpression at");
-          yield return new ForallExpr(tok, quantifier.RangeToken, quantifier.BoundVars, quantifier.Range, e, TriggerUtils.CopyAttributes(quantifier.Attributes)) { Type = quantifier.Type, Bounds = quantifier.Bounds };
+          yield return new ForallExpr(tok, quantifier.Origin, quantifier.BoundVars, quantifier.Range, e, TriggerUtils.CopyAttributes(quantifier.Attributes)) { Type = quantifier.Type, Bounds = quantifier.Bounds };
         }
       } else if (quantifier is ExistsExpr) {
         IEnumerable<Expression> stream;
@@ -94,7 +94,7 @@ private static IEnumerable<Expression> SplitQuantifier(ComprehensionExpr quantif
         }
         foreach (var e in stream) {
           var tok = body?.tok == e.tok ? quantifier.tok : new NestedOrigin(quantifier.tok, e.tok, "in subexpression at");
-          yield return new ExistsExpr(tok, quantifier.RangeToken, quantifier.BoundVars, quantifier.Range, e, TriggerUtils.CopyAttributes(quantifier.Attributes)) { Type = quantifier.Type, Bounds = quantifier.Bounds };
+          yield return new ExistsExpr(tok, quantifier.Origin, quantifier.BoundVars, quantifier.Range, e, TriggerUtils.CopyAttributes(quantifier.Attributes)) { Type = quantifier.Type, Bounds = quantifier.Bounds };
         }
       } else {
         yield return quantifier;
@@ -113,7 +113,7 @@ protected override void VisitOneExpr(Expression expr) {
         if (!splits.ContainsKey(quantifier) && AllowsSplitting(quantifier)) {
           splits[quantifier] = SplitQuantifier(quantifier).Select(e => {
             e.tok = new AutoGeneratedOrigin(e.tok);
-            e.RangeToken = e.RangeToken.MakeAutoGenerated();
+            e.RangeOrigin = e.Origin.MakeAutoGenerated();
             return e;
           }).ToList();
         }
diff --git a/Source/DafnyCore/Triggers/SplitPartTriggerWriter.cs b/Source/DafnyCore/Triggers/SplitPartTriggerWriter.cs
index 941e8151477..31667aadafb 100644
--- a/Source/DafnyCore/Triggers/SplitPartTriggerWriter.cs
+++ b/Source/DafnyCore/Triggers/SplitPartTriggerWriter.cs
@@ -102,10 +102,10 @@ public bool RewriteMatchingLoop(ErrorReporter reporter, ModuleDefinition module)
     } else {
       // make a copy of the expr
       if (expr is ForallExpr) {
-        expr = new ForallExpr(expr.tok, expr.RangeToken, expr.BoundVars, expr.Range, expr.Term,
+        expr = new ForallExpr(expr.tok, expr.Origin, expr.BoundVars, expr.Range, expr.Term,
           TriggerUtils.CopyAttributes(expr.Attributes)) { Type = expr.Type, Bounds = expr.Bounds };
       } else {
-        expr = new ExistsExpr(expr.tok, expr.RangeToken, expr.BoundVars, expr.Range, expr.Term,
+        expr = new ExistsExpr(expr.tok, expr.Origin, expr.BoundVars, expr.Range, expr.Term,
           TriggerUtils.CopyAttributes(expr.Attributes)) { Type = expr.Type, Bounds = expr.Bounds };
       }
     }
diff --git a/Source/DafnyCore/Verifier/BoogieGenerator.BoogieFactory.cs b/Source/DafnyCore/Verifier/BoogieGenerator.BoogieFactory.cs
index bd62df4e4c6..241ec61082f 100644
--- a/Source/DafnyCore/Verifier/BoogieGenerator.BoogieFactory.cs
+++ b/Source/DafnyCore/Verifier/BoogieGenerator.BoogieFactory.cs
@@ -896,8 +896,8 @@ static Bpl.Expr BplFormalVar(string name, Bpl.Type ty, bool incoming, List<Bpl.V
 
     public static IOrigin ToDafnyToken(bool reportRanges, Bpl.IToken boogieToken) {
       if (boogieToken is BoogieRangeOrigin boogieRangeToken) {
-        if (!reportRanges && boogieRangeToken.Center is not null) {
-          return boogieRangeToken.Center;
+        if (!reportRanges && boogieRangeToken.Centerish is not null) {
+          return boogieRangeToken.Centerish;
         }
 
         return new RangeToken(boogieRangeToken.StartToken, boogieRangeToken.EndToken);
@@ -912,7 +912,7 @@ public static IOrigin ToDafnyToken(bool reportRanges, Bpl.IToken boogieToken) {
       if (boogieToken == null) {
         return null;
       } else if (boogieToken is IOrigin dafnyToken) {
-        return dafnyToken;
+        return dafnyToken; // Do not return dafnyToken.center, because then BoogieGenerator loses RefinmentOrigin wrapping
       } else if (boogieToken is VCGeneration.TokenWrapper tokenWrapper) {
         return ToDafnyToken(reportRanges, tokenWrapper.Inner);
       } else if (boogieToken == Boogie.Token.NoToken) {
diff --git a/Source/DafnyCore/Verifier/BoogieGenerator.Decreases.cs b/Source/DafnyCore/Verifier/BoogieGenerator.Decreases.cs
index ff1359a62dc..3b7545fad1d 100644
--- a/Source/DafnyCore/Verifier/BoogieGenerator.Decreases.cs
+++ b/Source/DafnyCore/Verifier/BoogieGenerator.Decreases.cs
@@ -81,7 +81,7 @@ void CheckCallTermination(IOrigin tok, List<Expression> contextDecreases, List<E
       }
       oldExpressions.Add(e1);
       newExpressions.Add(e0direct);
-      toks.Add(new NestedOrigin(tok, e1.tok));
+      toks.Add(new NestedOrigin(tok, e1.Origin));
       callee.Add(etranCurrent.TrExpr(e0));
       caller.Add(etranCurrent.TrExpr(e1));
     }
diff --git a/Source/DafnyCore/Verifier/BoogieGenerator.ExpressionTranslator.cs b/Source/DafnyCore/Verifier/BoogieGenerator.ExpressionTranslator.cs
index ac21e062a60..9f9da2dccf0 100644
--- a/Source/DafnyCore/Verifier/BoogieGenerator.ExpressionTranslator.cs
+++ b/Source/DafnyCore/Verifier/BoogieGenerator.ExpressionTranslator.cs
@@ -646,7 +646,7 @@ public Boogie.Expr TrExpr(Expression expr) {
                 var mem = recv as MemberSelectExpr;
                 var fn = mem == null ? null : mem.Member as Function;
                 if (fn != null) {
-                  return TrExpr(new FunctionCallExpr(e.tok, fn.Name, mem.Obj, e.tok, e.CloseParen, e.Args) {
+                  return TrExpr(new FunctionCallExpr(e.tok, fn.Name, mem.Obj, Token.NoToken, e.CloseParen, e.Args) {
                     Function = fn,
                     Type = e.Type,
                     TypeApplication_AtEnclosingClass = mem.TypeApplicationAtEnclosingClass,
@@ -1513,7 +1513,7 @@ public Boogie.Expr TrExpr(Expression expr) {
 
             bool endsWithWinningTopComparison = N == oldArray.Length && N < newArray.Length;
             var allowNoChange = decreasesToExpr.AllowNoChange || endsWithWinningTopComparison;
-            List<IOrigin> toks = oldExprs.Zip(newExprs, (_, _) => (IOrigin)decreasesToExpr.RangeToken).ToList();
+            List<IOrigin> toks = oldExprs.Zip(newExprs, (_, _) => (IOrigin)decreasesToExpr.Origin).ToList();
             var decreasesExpr = BoogieGenerator.DecreasesCheck(toks, null,
               newExprsDafny, oldExprsDafny, newExprs, oldExprs, null,
               null, allowNoChange, false);
diff --git a/Source/DafnyCore/Verifier/BoogieGenerator.ExpressionWellformed.cs b/Source/DafnyCore/Verifier/BoogieGenerator.ExpressionWellformed.cs
index 8e04c832986..7afa704fb4d 100644
--- a/Source/DafnyCore/Verifier/BoogieGenerator.ExpressionWellformed.cs
+++ b/Source/DafnyCore/Verifier/BoogieGenerator.ExpressionWellformed.cs
@@ -694,7 +694,7 @@ public void CheckWellformedWithResult(Expression expr, WFOptions wfOptions,
                 // Note, in the following, the "##" makes the variable invisible in BVD.  An alternative would be to communicate
                 // to BVD what this variable stands for and display it as such to the user.
                 Type et = p.Type.Subst(e.GetTypeArgumentSubstitutions());
-                LocalVariable local = new LocalVariable(p.RangeToken, "##" + p.Name, et, p.IsGhost);
+                LocalVariable local = new LocalVariable(p.Origin, "##" + p.Name, et, p.IsGhost);
                 local.type = local.SyntacticType;  // resolve local here
                 var ie = new IdentifierExpr(local.Tok, local.AssignUniqueName(CurrentDeclaration.IdGenerator)) {
                   Var = local
diff --git a/Source/DafnyCore/Verifier/BoogieGenerator.Extremes.cs b/Source/DafnyCore/Verifier/BoogieGenerator.Extremes.cs
index 3825e266eb4..4c2c013d97b 100644
--- a/Source/DafnyCore/Verifier/BoogieGenerator.Extremes.cs
+++ b/Source/DafnyCore/Verifier/BoogieGenerator.Extremes.cs
@@ -294,7 +294,7 @@ Expression PrefixSubstitution(PrefixPredicate pp, Expression body) {
       Expression recursiveCallReceiver;
       List<Expression> recursiveCallArgs;
       pp.RecursiveCallParameters(pp.tok, pp.TypeArgs, pp.Ins, null, substMap, out recursiveCallReceiver, out recursiveCallArgs);
-      var ppCall = new FunctionCallExpr(pp.tok, pp.Name, recursiveCallReceiver, pp.tok, pp.tok, recursiveCallArgs);
+      var ppCall = new FunctionCallExpr(pp.tok, pp.Name, recursiveCallReceiver, Token.NoToken, Token.NoToken, recursiveCallArgs);
       ppCall.Function = pp;
       ppCall.Type = Type.Bool;
       ppCall.TypeApplication_AtEnclosingClass = pp.EnclosingClass.TypeArgs.ConvertAll(tp => (Type)new UserDefinedType(tp));
@@ -305,7 +305,7 @@ Expression PrefixSubstitution(PrefixPredicate pp, Expression body) {
       if (pp.ExtremePred is GreatestPredicate) {
         // forall k':ORDINAL | _k' LESS _k :: pp(_k', args)
         var smaller = Expression.CreateLess(kprime, k);
-        limitCalls = new ForallExpr(pp.tok, pp.RangeToken, new List<BoundVar> { kprimeVar }, smaller, ppCall, triggerAttr) {
+        limitCalls = new ForallExpr(pp.tok, pp.Origin, new List<BoundVar> { kprimeVar }, smaller, ppCall, triggerAttr) {
           Type = Type.Bool,
           Bounds = new List<BoundedPool>() { new AllocFreeBoundedPool(kprimeVar.Type) }
         };
@@ -318,7 +318,7 @@ Expression PrefixSubstitution(PrefixPredicate pp, Expression body) {
           ResolvedOp = BinaryExpr.ResolvedOpcode.LessThanLimit,
           Type = Type.Bool
         };
-        limitCalls = new ExistsExpr(pp.tok, pp.RangeToken, new List<BoundVar> { kprimeVar }, smaller, ppCall, triggerAttr) {
+        limitCalls = new ExistsExpr(pp.tok, pp.Origin, new List<BoundVar> { kprimeVar }, smaller, ppCall, triggerAttr) {
           Type = Type.Bool,
           Bounds = new List<BoundedPool>() { new AllocFreeBoundedPool(kprimeVar.Type) }
         };
diff --git a/Source/DafnyCore/Verifier/BoogieGenerator.Iterators.cs b/Source/DafnyCore/Verifier/BoogieGenerator.Iterators.cs
index fc49e51c660..fc037b9d54f 100644
--- a/Source/DafnyCore/Verifier/BoogieGenerator.Iterators.cs
+++ b/Source/DafnyCore/Verifier/BoogieGenerator.Iterators.cs
@@ -188,7 +188,7 @@ void AddIteratorWellformednessCheck(IteratorDecl iter, Procedure proc) {
         new List<Bpl.IdentifierExpr>()));
 
       // assume the automatic yield-requires precondition (which is always well-formed):  this.Valid()
-      var validCall = new FunctionCallExpr(iter.tok, "Valid", th, iter.tok, iter.tok, new List<Expression>());
+      var validCall = new FunctionCallExpr(iter.tok, "Valid", th, Token.NoToken, Token.NoToken, new List<Expression>());
       validCall.Function = iter.Member_Valid;  // resolve here
       validCall.Type = Type.Bool;  // resolve here
       validCall.TypeApplication_AtEnclosingClass = iter.TypeArgs.ConvertAll(tp => (Type)new UserDefinedType(tp));  // resolve here
diff --git a/Source/DafnyCore/Verifier/BoogieGenerator.Methods.cs b/Source/DafnyCore/Verifier/BoogieGenerator.Methods.cs
index 766227e0ac3..646c9f4a6b6 100644
--- a/Source/DafnyCore/Verifier/BoogieGenerator.Methods.cs
+++ b/Source/DafnyCore/Verifier/BoogieGenerator.Methods.cs
@@ -604,7 +604,7 @@ private StmtList TrMethodContractWellformednessCheck(Method m, ExpressionTransla
             Boogie.Expr wh = GetWhereClause(e.tok, etran.TrExpr(e), e.Type, etran.Old, ISALLOC, true);
             if (wh != null) {
               var desc = new IsAllocated("default value", "in the two-state lemma's previous state", e);
-              builder.Add(Assert(e.RangeToken, wh, desc, builder.Context));
+              builder.Add(Assert(e.Origin, wh, desc, builder.Context));
             }
           }
         }
@@ -762,7 +762,7 @@ private StmtList TrMethodBody(Method m, BoogieStmtListBuilder builder, Variables
           TypeApplicationJustMember = m.TypeArgs.ConvertAll(tp => (Type)new UserDefinedType(tp.tok, tp)),
           Type = new InferredTypeProxy()
         };
-        var recursiveCall = new CallStmt(m.tok.ToRange(), new List<Expression>(), methodSel, recursiveCallArgs) {
+        var recursiveCall = new CallStmt(m.tok, new List<Expression>(), methodSel, recursiveCallArgs) {
           IsGhost = m.IsGhost
         };
 
@@ -820,11 +820,11 @@ private StmtList TrMethodBody(Method m, BoogieStmtListBuilder builder, Variables
       m.Outs.ForEach(p => AddExistingDefiniteAssignmentTracker(p, m.IsGhost));
       // translate the body
       TrStmt(m.Body, builder, localVariables, etran);
-      m.Outs.ForEach(p => CheckDefiniteAssignmentReturn(m.Body.RangeToken.EndToken, p, builder));
+      m.Outs.ForEach(p => CheckDefiniteAssignmentReturn(m.Body.Origin.EndToken, p, builder));
       if (m is { FunctionFromWhichThisIsByMethodDecl: { ByMethodTok: { } } fun }) {
         AssumeCanCallForByMethodDecl(m, builder);
       }
-      var stmts = builder.Collect(m.Body.RangeToken.StartToken); // EndToken might make more sense, but it requires updating most of the regression tests.
+      var stmts = builder.Collect(m.Body.Origin.StartToken); // EndToken might make more sense, but it requires updating most of the regression tests.
       DefiniteAssignmentTrackers = beforeOutTrackers;
       return stmts;
     }
@@ -1495,7 +1495,7 @@ private void AddMethodOverrideEnsChk(Method m, BoogieStmtListBuilder builder, Ex
           var constraint = allOverrideEns == null
             ? null
             : new BinaryExpr(Token.NoToken, BinaryExpr.Opcode.Imp, allOverrideEns, subEn);
-          builder.Add(Assert(m.RangeToken, s.E, new EnsuresStronger(constraint), builder.Context));
+          builder.Add(Assert(m.Origin, s.E, new EnsuresStronger(constraint), builder.Context));
         }
       }
     }
@@ -1524,7 +1524,7 @@ private void AddMethodOverrideReqsChk(Method m, BoogieStmtListBuilder builder, E
           var constraint = allTraitReqs == null
             ? null
             : new BinaryExpr(Token.NoToken, BinaryExpr.Opcode.Imp, allTraitReqs, req.E);
-          builder.Add(Assert(m.RangeToken, s.E, new RequiresWeaker(constraint), builder.Context));
+          builder.Add(Assert(m.Origin, s.E, new RequiresWeaker(constraint), builder.Context));
         }
       }
     }
@@ -1564,7 +1564,7 @@ private void AddOverrideTerminationChk(ICallable original, ICallable overryd, Bo
           N = i;
           break;
         }
-        toks.Add(new NestedOrigin(original.RangeToken.StartToken, e1.tok));
+        toks.Add(new NestedOrigin(original.Origin.StartToken, e1.tok));
         calleeDafny.Add(e0);
         callerDafny.Add(e1);
         callee.Add(etran.TrExpr(e0));
@@ -1608,7 +1608,7 @@ private void AddOverrideTerminationChk(ICallable original, ICallable overryd, Bo
         calleeDecreases,
         true);
       var desc = new TraitDecreases(original.WhatKind, assertedExpr);
-      builder.Add(Assert(original.RangeToken, decrChk, desc, builder.Context));
+      builder.Add(Assert(original.Origin, decrChk, desc, builder.Context));
     }
 
     private void AddMethodOverrideFrameSubsetChk(Method m, bool isModifies, BoogieStmtListBuilder builder, ExpressionTranslator etran, Variables localVariables,
@@ -1654,12 +1654,12 @@ private void AddMethodOverrideFrameSubsetChk(Method m, bool isModifies, BoogieSt
       var q = new Boogie.ForallExpr(tok, new List<TypeVariable>(), new List<Variable> { oVar, fVar },
         BplImp(BplAnd(ante, oInCallee), consequent2));
       var description = new TraitFrame(m.WhatKind, isModifies, classFrameExps, traitFrameExps);
-      builder.Add(Assert(m.RangeToken, q, description, builder.Context, kv));
+      builder.Add(Assert(m.Origin, q, description, builder.Context, kv));
     }
 
     // Return a way to know if an assertion should be converted to an assumption
     private void SetAssertionOnlyFilter(Node m) {
-      List<RangeToken> rangesOnly = new List<RangeToken>();
+      var rangesOnly = new List<IOrigin>();
       m.Visit(node => {
         if (node is AssertStmt assertStmt &&
             assertStmt.HasAssertOnlyAttribute(out var assertOnlyKind)) {
@@ -1679,7 +1679,7 @@ private void SetAssertionOnlyFilter(Node m) {
               new RangeToken(m.StartToken, assertStmt.EndToken) :
               assertOnlyKind == AssertStmt.AssertOnlyKind.After ?
               new RangeToken(assertStmt.StartToken, ifAfterLastToken)
-              : assertStmt.RangeToken;
+              : assertStmt.Origin;
           if (assertOnlyKind == AssertStmt.AssertOnlyKind.Before && rangesOnly.Any(other => rangeToAdd.Intersects(other))) {
             // There are more precise ranges so we don't add this one
             return true;
diff --git a/Source/DafnyCore/Verifier/BoogieGenerator.cs b/Source/DafnyCore/Verifier/BoogieGenerator.cs
index 88bdae2c571..f1f2de670a3 100644
--- a/Source/DafnyCore/Verifier/BoogieGenerator.cs
+++ b/Source/DafnyCore/Verifier/BoogieGenerator.cs
@@ -2447,7 +2447,7 @@ void CloneVariableAsBoundVar(IOrigin tok, IVariable iv, string prefix, out Bound
 
       bv = new BoundVar(tok, CurrentIdGenerator.FreshId(prefix), iv.Type); // use this temporary variable counter, but for a Dafny name (the idea being that the number and the initial "_" in the name might avoid name conflicts)
       ie = new IdentifierExpr(tok, bv.Name);
-      bv.RangeToken = iv.RangeToken;
+      bv.RangeOrigin = iv.Origin;
       ie.Var = bv;  // resolve here
       ie.Type = bv.Type;  // resolve here
     }
@@ -3299,11 +3299,15 @@ public static IOrigin Unwrap(IOrigin tok) {
         Contract.Requires(tok != null);
         Contract.Ensures(Contract.Result<IOrigin>() != null);
         var ftok = tok as ForceCheckOrigin;
-        return ftok != null ? ftok.WrappedToken : tok;
+        return ftok != null ? ftok.WrappedOrigin : tok;
       }
 
       public override IOrigin WithVal(string newVal) {
-        return new ForceCheckOrigin(WrappedToken.WithVal(newVal));
+        return new ForceCheckOrigin(WrappedOrigin.WithVal(newVal));
+      }
+
+      public override bool IsInherited(ModuleDefinition d) {
+        return false;
       }
     }
 
@@ -3412,7 +3416,7 @@ public Bpl.StmtList TrStmt2StmtList(BoogieStmtListBuilder builder,
       Contract.Requires(codeContext != null && Predef != null);
       Contract.Ensures(Contract.Result<Bpl.StmtList>() != null);
 
-      TrStmtList(new List<Statement> { block }, builder, locals, etran, introduceScope ? block.RangeToken : null, processLabels: false);
+      TrStmtList(new List<Statement> { block }, builder, locals, etran, introduceScope ? block.Origin : null, processLabels: false);
       return builder.Collect(block.Tok);  // TODO: would be nice to have an end-curly location for "block"
     }
 
@@ -3517,7 +3521,7 @@ Dictionary<IVariable, Expression> SetupBoundVarsAsLocals(List<BoundVar> boundVar
       typeAntecedent = Bpl.Expr.True;
       var substMap = new Dictionary<IVariable, Expression>();
       foreach (BoundVar bv in boundVars) {
-        LocalVariable local = new LocalVariable(bv.RangeToken, nameSuffix == null ? bv.Name : bv.Name + nameSuffix, bv.Type, bv.IsGhost);
+        LocalVariable local = new LocalVariable(bv.Origin, nameSuffix == null ? bv.Name : bv.Name + nameSuffix, bv.Type, bv.IsGhost);
         local.type = local.SyntacticType;  // resolve local here
         IdentifierExpr ie = new IdentifierExpr(local.Tok, local.AssignUniqueName(CurrentDeclaration.IdGenerator));
         ie.Var = local; ie.Type = ie.Var.Type;  // resolve ie here
@@ -3562,7 +3566,7 @@ Bpl.Expr SetupVariableAsLocal(IVariable v, Dictionary<IVariable, Expression> sub
       Contract.Requires(locals != null);
       Contract.Requires(etran != null);
 
-      var local = new LocalVariable(v.RangeToken, v.Name, v.Type, v.IsGhost);
+      var local = new LocalVariable(v.Origin, v.Name, v.Type, v.IsGhost);
       local.type = local.SyntacticType;  // resolve local here
       var ie = new IdentifierExpr(local.Tok, local.AssignUniqueName(CurrentDeclaration.IdGenerator));
       ie.Var = local; ie.Type = ie.Var.Type;  // resolve ie here
@@ -4055,7 +4059,7 @@ public BoogieWrapper(Bpl.Expr expr, Type dafnyType)
         : base(ToDafnyToken(false, expr.tok)) {
         Contract.Requires(expr != null);
         Contract.Requires(dafnyType != null);
-        RangeToken = ToDafnyToken(true, expr.tok).ToRange();
+        RangeOrigin = ToDafnyToken(true, expr.tok);
         Expr = expr;
         Type = dafnyType;  // resolve immediately
       }
diff --git a/Source/DafnyCore/Verifier/CaptureStateExtensions.cs b/Source/DafnyCore/Verifier/CaptureStateExtensions.cs
index a8e7e6bf1bc..38dad4db45b 100644
--- a/Source/DafnyCore/Verifier/CaptureStateExtensions.cs
+++ b/Source/DafnyCore/Verifier/CaptureStateExtensions.cs
@@ -16,7 +16,7 @@ internal static void AddCaptureState(this BoogieStmtListBuilder builder, Stateme
     private static Bpl.Cmd CaptureState(DafnyOptions options, Statement stmt) {
       Contract.Requires(stmt != null);
       Contract.Ensures(Contract.Result<Bpl.Cmd>() != null);
-      return CaptureState(options, stmt.RangeToken.EndToken, true, null);
+      return CaptureState(options, stmt.Origin.EndToken, true, null);
     }
 
     internal static void AddCaptureState(this BoogieStmtListBuilder builder, IOrigin tok, bool isEndToken, string /*?*/ additionalInfo) {
diff --git a/Source/DafnyCore/Verifier/Datatypes/BoogieGenerator.DataTypes.cs b/Source/DafnyCore/Verifier/Datatypes/BoogieGenerator.DataTypes.cs
index 972769b47ee..81810a395e4 100644
--- a/Source/DafnyCore/Verifier/Datatypes/BoogieGenerator.DataTypes.cs
+++ b/Source/DafnyCore/Verifier/Datatypes/BoogieGenerator.DataTypes.cs
@@ -165,7 +165,7 @@ private void AddCoDatatypeDeclAxioms(CoDatatypeDecl codecl) {
         (typeOfK, K) => {
           Func<string, List<TypeParameter>> renew = s =>
             Map(codecl.TypeArgs, tp =>
-              new TypeParameter(tp.RangeToken, tp.NameNode.Append("#" + s), tp.PositionalIndex, tp.Parent));
+              new TypeParameter(tp.Origin, tp.NameNode.Append("#" + s), tp.PositionalIndex, tp.Parent));
           List<TypeParameter> typaramsL = renew("l"), typaramsR = renew("r");
           var lvars = MkTyParamBinders(typaramsL, out var lexprs);
           var rvars = MkTyParamBinders(typaramsR, out var rexprs);
diff --git a/Source/DafnyCore/Verifier/ProofDependency.cs b/Source/DafnyCore/Verifier/ProofDependency.cs
index 7037bc02537..4bb0c198fcf 100644
--- a/Source/DafnyCore/Verifier/ProofDependency.cs
+++ b/Source/DafnyCore/Verifier/ProofDependency.cs
@@ -18,7 +18,7 @@ namespace DafnyCore.Verifier;
 public abstract class ProofDependency {
   public abstract string Description { get; }
 
-  public abstract RangeToken Range { get; }
+  public abstract IOrigin Range { get; }
 
   public string LocationString() {
     if (Range?.StartToken is null) {
@@ -52,7 +52,7 @@ public string OriginalString() {
 // assertion batch can be proved without proving one of the assertions that is
 // a proof obligation within it, that assertion must have been proved vacuously.
 public class ProofObligationDependency : ProofDependency {
-  public override RangeToken Range { get; }
+  public override IOrigin Range { get; }
 
   public ProofObligationDescription ProofObligation { get; }
 
@@ -60,13 +60,13 @@ public class ProofObligationDependency : ProofDependency {
       $"{ProofObligation.SuccessDescription}";
 
   public ProofObligationDependency(Microsoft.Boogie.IToken tok, ProofObligationDescription proofObligation) {
-    Range = tok as RangeToken ?? (proofObligation as AssertStatementDescription)?.AssertStatement.RangeToken ?? BoogieGenerator.ToDafnyToken(true, tok).ToRange();
+    Range = tok as RangeToken ?? (proofObligation as AssertStatementDescription)?.AssertStatement.Origin ?? BoogieGenerator.ToDafnyToken(true, tok);
     ProofObligation = proofObligation;
   }
 }
 
 public class AssumedProofObligationDependency : ProofDependency {
-  public override RangeToken Range { get; }
+  public override IOrigin Range { get; }
 
   public ProofObligationDescription ProofObligation { get; }
 
@@ -74,7 +74,10 @@ public class AssumedProofObligationDependency : ProofDependency {
       $"assumption that {ProofObligation.SuccessDescription}";
 
   public AssumedProofObligationDependency(IOrigin tok, ProofObligationDescription proofObligation) {
-    Range = tok as RangeToken ?? (proofObligation as AssertStatementDescription)?.AssertStatement.RangeToken ?? new RangeToken(tok, tok);
+    var unwrapped = tok.Unwrap();
+    Range = unwrapped as RangeToken
+      ?? ((proofObligation as AssertStatementDescription)?.AssertStatement.Origin
+         ?? new RangeToken((Token)unwrapped, (Token)unwrapped));
     ProofObligation = proofObligation;
   }
 }
@@ -86,8 +89,8 @@ public class RequiresDependency : ProofDependency {
 
   private IOrigin tok;
 
-  public override RangeToken Range =>
-    tok as RangeToken ?? requires.RangeToken;
+  public override IOrigin Range =>
+    tok as RangeToken ?? requires.Origin;
 
   public override string Description =>
     $"requires clause";
@@ -104,8 +107,8 @@ public class EnsuresDependency : ProofDependency {
 
   private readonly IOrigin tok;
 
-  public override RangeToken Range =>
-    tok as RangeToken ?? ensures.RangeToken;
+  public override IOrigin Range =>
+    tok as RangeToken ?? ensures.Origin;
 
   public override string Description =>
     "ensures clause";
@@ -122,8 +125,7 @@ public class CallRequiresDependency : ProofDependency {
   public readonly CallDependency call;
   private readonly RequiresDependency requires;
 
-  public override RangeToken Range =>
-    call.Range;
+  public override IOrigin Range => call.Range;
 
   public override string Description =>
     $"requires clause at {requires.RangeString()} from call";
@@ -140,8 +142,7 @@ public class CallEnsuresDependency : ProofDependency {
   public readonly CallDependency call;
   private readonly EnsuresDependency ensures;
 
-  public override RangeToken Range =>
-    call.Range;
+  public override IOrigin Range => call.Range;
 
   public override string Description =>
     $"ensures clause at {ensures.RangeString()} from call";
@@ -156,8 +157,7 @@ public CallEnsuresDependency(CallDependency call, EnsuresDependency ensures) {
 public class CallDependency : ProofDependency {
   public readonly CallStmt call;
 
-  public override RangeToken Range =>
-    call.RangeToken;
+  public override IOrigin Range => call.Origin;
 
   public override string Description =>
     $"call";
@@ -169,8 +169,7 @@ public CallDependency(CallStmt call) {
 
 // Represents the assumption of a predicate in an `assume` statement.
 public class AssumptionDependency : ProofDependency {
-  public override RangeToken Range =>
-    Expr.RangeToken;
+  public override IOrigin Range => Expr.Origin;
 
   public override string Description =>
     comment ?? OriginalString();
@@ -192,8 +191,7 @@ public AssumptionDependency(bool warnWhenUnused, string comment, Expression expr
 public class InvariantDependency : ProofDependency {
   private readonly Expression invariant;
 
-  public override RangeToken Range =>
-    invariant.RangeToken;
+  public override IOrigin Range => invariant.Origin;
 
   public override string Description =>
     $"loop invariant";
@@ -206,19 +204,19 @@ public InvariantDependency(Expression invariant) {
 // Represents an assignment statement. This includes the assignment to an
 // out parameter implicit in a return statement.
 public class AssignmentDependency : ProofDependency {
-  public override RangeToken Range { get; }
+  public override IOrigin Range { get; }
 
   public override string Description =>
      "assignment (or return)";
 
-  public AssignmentDependency(RangeToken rangeOrigin) {
-    this.Range = rangeOrigin;
+  public AssignmentDependency(IOrigin rangeToken) {
+    this.Range = rangeToken;
   }
 }
 
 // Represents dependency of a proof on the definition of a specific function.
 public class FunctionDefinitionDependency : ProofDependency {
-  public override RangeToken Range => function.RangeToken;
+  public override IOrigin Range => function.Origin;
 
   public override string Description =>
     $"function definition for {function.Name}";
diff --git a/Source/DafnyCore/Verifier/ProofObligationDescription.cs b/Source/DafnyCore/Verifier/ProofObligationDescription.cs
index 1dd5f7d562c..bb6114a913a 100644
--- a/Source/DafnyCore/Verifier/ProofObligationDescription.cs
+++ b/Source/DafnyCore/Verifier/ProofObligationDescription.cs
@@ -1779,7 +1779,7 @@ public LetSuchThatExists(List<BoundVar> bvars, Expression condition) {
     this.bvars = bvars;
   }
   public override Expression GetAssertedExpr(DafnyOptions options) {
-    return new ExistsExpr(bvars[0].tok, bvars[0].RangeToken, bvars,
+    return new ExistsExpr(bvars[0].tok, bvars[0].Origin, bvars,
       null, condition, null);
   }
 }
diff --git a/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrAssignment.cs b/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrAssignment.cs
index 8535740a95b..11fe7687a1b 100644
--- a/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrAssignment.cs
+++ b/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrAssignment.cs
@@ -241,7 +241,7 @@ void ProcessLhss(List<Expression> lhss, bool rhsCanAffectPreviouslyKnownExpressi
         lhsBuilders.Add(delegate (Bpl.Expr rhs, bool origRhsIsHavoc, BoogieStmtListBuilder bldr, ExpressionTranslator et) {
           if (rhs != null) {
             var cmd = Bpl.Cmd.SimpleAssign(tok, bLhs, rhs);
-            proofDependencies?.AddProofDependencyId(cmd, lhs.tok, new AssignmentDependency(stmt.RangeToken));
+            proofDependencies?.AddProofDependencyId(cmd, lhs.tok, new AssignmentDependency(stmt.Origin));
             bldr.Add(cmd);
           }
 
@@ -274,7 +274,7 @@ void ProcessLhss(List<Expression> lhss, bool rhsCanAffectPreviouslyKnownExpressi
           lhsBuilders.Add(delegate (Bpl.Expr rhs, bool origRhsIsHavoc, BoogieStmtListBuilder bldr, ExpressionTranslator et) {
             if (rhs != null) {
               var cmd = Bpl.Cmd.SimpleAssign(tok, bLhs, rhs);
-              proofDependencies?.AddProofDependencyId(cmd, fse.tok, new AssignmentDependency(stmt.RangeToken));
+              proofDependencies?.AddProofDependencyId(cmd, fse.tok, new AssignmentDependency(stmt.Origin));
               bldr.Add(cmd);
             }
 
@@ -291,7 +291,7 @@ void ProcessLhss(List<Expression> lhss, bool rhsCanAffectPreviouslyKnownExpressi
               Check_NewRestrictions(tok, fse.Obj, obj, fseField, rhs, bldr, et);
               var h = (Bpl.IdentifierExpr)et.HeapExpr;  // TODO: is this cast always justified?
               var cmd = Bpl.Cmd.SimpleAssign(tok, h, UpdateHeap(tok, h, obj, new Bpl.IdentifierExpr(tok, GetField(fseField)), rhs));
-              proofDependencies?.AddProofDependencyId(cmd, lhs.tok, new AssignmentDependency(stmt.RangeToken));
+              proofDependencies?.AddProofDependencyId(cmd, lhs.tok, new AssignmentDependency(stmt.Origin));
               bldr.Add(cmd);
               // assume $IsGoodHeap($Heap);
               bldr.Add(AssumeGoodHeap(tok, et));
@@ -321,7 +321,7 @@ void ProcessLhss(List<Expression> lhss, bool rhsCanAffectPreviouslyKnownExpressi
           if (rhs != null) {
             var h = (Bpl.IdentifierExpr)et.HeapExpr;  // TODO: is this cast always justified?
             var cmd = Bpl.Cmd.SimpleAssign(tok, h, UpdateHeap(tok, h, obj, fieldName, rhs));
-            proofDependencies?.AddProofDependencyId(cmd, lhs.tok, new AssignmentDependency(stmt.RangeToken));
+            proofDependencies?.AddProofDependencyId(cmd, lhs.tok, new AssignmentDependency(stmt.Origin));
             bldr.Add(cmd);
             // assume $IsGoodHeap($Heap);
             bldr.Add(AssumeGoodHeap(tok, et));
@@ -346,7 +346,7 @@ void ProcessLhss(List<Expression> lhss, bool rhsCanAffectPreviouslyKnownExpressi
           if (rhs != null) {
             var h = (Bpl.IdentifierExpr)et.HeapExpr;  // TODO: is this cast always justified?
             var cmd = Bpl.Cmd.SimpleAssign(tok, h, UpdateHeap(tok, h, obj, fieldName, rhs));
-            proofDependencies?.AddProofDependencyId(cmd, lhs.tok, new AssignmentDependency(stmt.RangeToken));
+            proofDependencies?.AddProofDependencyId(cmd, lhs.tok, new AssignmentDependency(stmt.Origin));
             bldr.Add(cmd);
             // assume $IsGoodHeap($Heap);
             bldr.Add(AssumeGoodHeap(tok, etran));
@@ -435,13 +435,13 @@ Bpl.Expr TrAssignmentRhs(IOrigin tok, Bpl.IdentifierExpr bGivenLhs, IVariable lh
         Contract.Assert(bGivenLhs == bLhs);
         // box the RHS, then do the assignment
         var cmd = Bpl.Cmd.SimpleAssign(tok, bGivenLhs, AdaptBoxing(tok, bRhs, e.Expr.Type, lhsType));
-        proofDependencies?.AddProofDependencyId(cmd, tok, new AssignmentDependency(stmt.RangeToken));
+        proofDependencies?.AddProofDependencyId(cmd, tok, new AssignmentDependency(stmt.Origin));
         builder.Add(cmd);
         return bGivenLhs;
       } else {
         // box from RHS type to tmp-var type, then do the assignment; then return LHS, boxed from tmp-var type to result type
         var cmd = Bpl.Cmd.SimpleAssign(tok, bLhs, AdaptBoxing(tok, bRhs, e.Expr.Type, rhsTypeConstraint));
-        proofDependencies?.AddProofDependencyId(cmd, tok, new AssignmentDependency(stmt.RangeToken));
+        proofDependencies?.AddProofDependencyId(cmd, tok, new AssignmentDependency(stmt.Origin));
         builder.Add(cmd);
         return CondApplyBox(tok, bLhs, rhsTypeConstraint, lhsType);
       }
@@ -540,13 +540,13 @@ Bpl.Expr TrAssignmentRhs(IOrigin tok, Bpl.IdentifierExpr bGivenLhs, IVariable lh
         Contract.Assert(bGivenLhs == bLhs);
         // box the RHS, then do the assignment
         var cmd = Bpl.Cmd.SimpleAssign(tok, bGivenLhs, CondApplyBox(tok, nw, tRhs.Type, lhsType));
-        proofDependencies?.AddProofDependencyId(cmd, tok, new AssignmentDependency(stmt.RangeToken));
+        proofDependencies?.AddProofDependencyId(cmd, tok, new AssignmentDependency(stmt.Origin));
         builder.Add(cmd);
         return bGivenLhs;
       } else {
         // do the assignment, then box the result
         var cmd = Bpl.Cmd.SimpleAssign(tok, bLhs, nw);
-        proofDependencies?.AddProofDependencyId(cmd, tok, new AssignmentDependency(stmt.RangeToken));
+        proofDependencies?.AddProofDependencyId(cmd, tok, new AssignmentDependency(stmt.Origin));
         builder.Add(cmd);
         return CondApplyBox(tok, bLhs, tRhs.Type, lhsType);
       }
diff --git a/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrCall.cs b/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrCall.cs
index 26a7f2f58b5..f6f763880b3 100644
--- a/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrCall.cs
+++ b/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrCall.cs
@@ -182,7 +182,7 @@ void ProcessCallStmt(CallStmt cs, Dictionary<TypeParameter, Type> tySubst, Bpl.E
     var directSubstMap = new Dictionary<IVariable, Expression>();
     for (int i = 0; i < callee.Ins.Count; i++) {
       var formal = callee.Ins[i];
-      var local = new LocalVariable(formal.RangeToken, formal.Name + "#", formal.Type.Subst(tySubst), formal.IsGhost);
+      var local = new LocalVariable(formal.Origin, formal.Name + "#", formal.Type.Subst(tySubst), formal.IsGhost);
       local.type = local.SyntacticType;  // resolve local here
       var localName = local.AssignUniqueName(CurrentDeclaration.IdGenerator);
       var ie = new IdentifierExpr(local.Tok, localName);
diff --git a/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrLoop.cs b/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrLoop.cs
index 23dd10614ed..d32b5ca0c3e 100644
--- a/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrLoop.cs
+++ b/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrLoop.cs
@@ -104,7 +104,7 @@ private void TrForLoop(ForLoopStmt stmt, BoogieStmtListBuilder builder, Variable
         Expression dafnyRange = dafnyRangeBounds.Count == 1
           ? dafnyRangeBounds[0]
           : new BinaryExpr(stmt.tok, BinaryExpr.Opcode.And, dafnyRangeBounds[0], dafnyRangeBounds[1]);
-        var dafnyAssertion = new ForallExpr(stmt.tok, stmt.RangeToken, new List<BoundVar> { indexVar },
+        var dafnyAssertion = new ForallExpr(stmt.tok, stmt.Origin, new List<BoundVar> { indexVar },
           dafnyRange, new TypeTestExpr(indexVar.tok, dIndex, indexVar.Type), null);
         builder.Add(Assert(tok, cre, new ForRangeAssignable(desc, dafnyAssertion), builder.Context));
       }
@@ -374,7 +374,7 @@ void TrLoop(LoopStmt loop, Expression Guard, BodyTranslator/*?*/ bodyTr,
             loopBodyBuilder, " at end of loop iteration", false, false);
           var description = new
             Terminates(loop.InferredDecreases, prevGhostLocals, null, initDecrsDafny, theDecreases, false);
-          loopBodyBuilder.Add(Assert(loop.Tok, decrCheck, description, builder.Context));
+          loopBodyBuilder.Add(Assert(loop.Center, decrCheck, description, builder.Context));
         }
       }
     } else if (isBodyLessLoop) {
diff --git a/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrPredicateStatement.cs b/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrPredicateStatement.cs
index 37d99c19407..6501a9ab316 100644
--- a/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrPredicateStatement.cs
+++ b/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrPredicateStatement.cs
@@ -100,7 +100,7 @@ public void TrAssertStmt(PredicateStmt stmt, BoogieStmtListBuilder builder, Vari
           var substMap = new Dictionary<IVariable, Expression>();
           foreach (var v in FreeVariablesUtil.ComputeFreeVariables(options, assertStmt.Expr)) {
             if (v is LocalVariable) {
-              var vcopy = new LocalVariable(stmt.RangeToken, string.Format("##{0}#{1}", name, v.Name), v.Type,
+              var vcopy = new LocalVariable(stmt.Origin, string.Format("##{0}#{1}", name, v.Name), v.Type,
                 v.IsGhost);
               vcopy.type = vcopy.SyntacticType; // resolve local here
               IdentifierExpr ie = new IdentifierExpr(vcopy.Tok,
diff --git a/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrStatement.cs b/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrStatement.cs
index 9bd4173436d..76e270800b0 100644
--- a/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrStatement.cs
+++ b/Source/DafnyCore/Verifier/Statements/BoogieGenerator.TrStatement.cs
@@ -266,7 +266,7 @@ public void TrStmt(Statement stmt, BoogieStmtListBuilder builder,
 
       // The "new;" translates into an allocation of "this"
       AddComment(builder, stmt, "new;");
-      fields.ForEach(f => CheckDefiniteAssignmentSurrogate(s.SeparatorTok ?? s.RangeToken.EndToken, f, true, builder));
+      fields.ForEach(f => CheckDefiniteAssignmentSurrogate(s.SeparatorTok ?? s.Origin.EndToken, f, true, builder));
       DefiniteAssignmentTrackers = beforeTrackers;
       var th = new ThisExpr(cl);
       var bplThis = (Bpl.IdentifierExpr)etran.TrExpr(th);
@@ -290,7 +290,7 @@ public void TrStmt(Statement stmt, BoogieStmtListBuilder builder,
       BlockByProofStmtVerifier.EmitBoogie(this, blockByProof, builder, locals, etran, codeContext);
     } else if (stmt is BlockStmt blockStmt) {
       var previousTrackers = DefiniteAssignmentTrackers;
-      TrStmtList(blockStmt.Body, builder, locals, etran, blockStmt.RangeToken);
+      TrStmtList(blockStmt.Body, builder, locals, etran, blockStmt.Origin);
       DefiniteAssignmentTrackers = previousTrackers;
     } else if (stmt is IfStmt ifStmt) {
       IfStatementVerifier.EmitBoogie(this, ifStmt, builder, locals, etran);
@@ -666,7 +666,7 @@ void TrAlternatives(List<GuardedAlternative> alternatives, IOrigin elseToken, Ac
         b.Add(TrAssumeCmdWithDependencies(etran, alternative.Guard.tok, alternative.Guard, "alternative guard"));
       }
       var prevDefiniteAssignmentTrackers = DefiniteAssignmentTrackers;
-      TrStmtList(alternative.Body, b, locals, etran, alternative.RangeToken);
+      TrStmtList(alternative.Body, b, locals, etran, alternative.Origin);
       DefiniteAssignmentTrackers = prevDefiniteAssignmentTrackers;
       Bpl.StmtList thn = b.Collect(alternative.Tok);
       elsIf = new Bpl.IfCmd(alternative.Tok, null, thn, elsIf, els);
@@ -796,7 +796,7 @@ public void IntroduceAndAssignExistentialVars(ExistsExpr exists, BoogieStmtListB
   }
 
   public void TrStmtList(List<Statement> stmts, BoogieStmtListBuilder builder, Variables locals, ExpressionTranslator etran,
-    RangeToken scopeRange = null, bool processLabels = true) {
+    IOrigin scopeRange = null, bool processLabels = true) {
     Contract.Requires(stmts != null);
     Contract.Requires(builder != null);
     Contract.Requires(locals != null);
diff --git a/Source/DafnyCore/Verifier/Statements/OpaqueBlockVerifier.cs b/Source/DafnyCore/Verifier/Statements/OpaqueBlockVerifier.cs
index 1035b84138f..8e6d0d5320a 100644
--- a/Source/DafnyCore/Verifier/Statements/OpaqueBlockVerifier.cs
+++ b/Source/DafnyCore/Verifier/Statements/OpaqueBlockVerifier.cs
@@ -15,7 +15,7 @@ public static void EmitBoogie(BoogieGenerator generator, OpaqueBlock block, Boog
 
     var bodyTranslator = GetBodyTranslator(generator, block, locals, etran, hasModifiesClause, blockBuilder);
     var prevDefiniteAssignmentTrackers = generator.DefiniteAssignmentTrackers;
-    generator.TrStmtList(block.Body, blockBuilder, locals, bodyTranslator, block.RangeToken);
+    generator.TrStmtList(block.Body, blockBuilder, locals, bodyTranslator, block.Origin);
     generator.DefiniteAssignmentTrackers = prevDefiniteAssignmentTrackers;
 
     var assignedVariables = block.DescendantsAndSelf.
@@ -28,7 +28,7 @@ public static void EmitBoogie(BoogieGenerator generator, OpaqueBlock block, Boog
     var implicitAssignedIdentifiers =
       variablesUsedInEnsures.Where(v => assignedVariables.Contains(v.Var) && generator.DefiniteAssignmentTrackers.ContainsKey(v.Var.UniqueName));
     foreach (var v in implicitAssignedIdentifiers) {
-      var expression = new AttributedExpression(Expression.CreateAssigned(v.Tok, v));
+      var expression = new AttributedExpression(v.Origin, Expression.CreateAssigned(v.Tok, v));
       totalEnsures.Add(expression);
       blockBuilder.Add(generator.Assert(
         v.Tok, etran.TrExpr(expression.E),
diff --git a/Source/DafnyDriver/CliCompilation.cs b/Source/DafnyDriver/CliCompilation.cs
index 33f30e71dd6..2f69642414f 100644
--- a/Source/DafnyDriver/CliCompilation.cs
+++ b/Source/DafnyDriver/CliCompilation.cs
@@ -234,7 +234,7 @@ string OriginDescription(IImplementationPartOrigin origin, bool outer) {
       yield break;
     }
 
-    var canVerifies = resolution.CanVerifies?.ToList();
+    var canVerifies = resolution.CanVerifies?.ToList(); // TODO remove ToList
 
     if (canVerifies == null) {
       yield break;
@@ -247,10 +247,10 @@ string OriginDescription(IImplementationPartOrigin origin, bool outer) {
 
     int done = 0;
 
-    var canVerifiesPerModule = canVerifies.GroupBy(c => c.ContainingModule);
-    foreach (var canVerifiesForModule in canVerifiesPerModule.
-               OrderBy(v => v.Key.Tok.pos)) {
-      var toAwait = new List<ICanVerify>();
+    var canVerifiesPerModule = canVerifies.GroupBy(c => c.ContainingModule).
+      OrderBy(v => v.Key.Tok.pos);
+    foreach (var canVerifiesForModule in canVerifiesPerModule) {
+      var toWaitFor = new List<ICanVerify>();
       foreach (var canVerify in canVerifiesForModule.OrderBy(v => v.Tok.pos)) {
         var results = new CliCanVerifyState();
         canVerifyResults[canVerify] = results;
@@ -260,11 +260,11 @@ string OriginDescription(IImplementationPartOrigin origin, bool outer) {
 
         var shouldVerify = await Compilation.VerifyLocation(canVerify.Tok.GetFilePosition(), results.TaskFilter, randomSeed);
         if (shouldVerify) {
-          toAwait.Add(canVerify);
+          toWaitFor.Add(canVerify);
         }
       }
 
-      foreach (var canVerify in toAwait) {
+      foreach (var canVerify in toWaitFor) {
         var results = canVerifyResults[canVerify];
         try {
           if (Options.Get(CommonOptionBag.ProgressOption) > CommonOptionBag.ProgressLevel.None) {
@@ -347,7 +347,7 @@ private List<ICanVerify> FilterCanVerifies(List<ICanVerify> canVerifies, out int
     var parsedLine = int.Parse(linePart);
     line = parsedLine;
     return fileFiltered.Where(c =>
-        c.RangeToken.StartToken.line <= parsedLine && parsedLine <= c.RangeToken.EndToken.line).ToList();
+        c.Origin.StartToken.line <= parsedLine && parsedLine <= c.Origin.EndToken.line).ToList();
   }
 
   private bool KeepVerificationTask(IVerificationTask task, int line) {
diff --git a/Source/DafnyDriver/CoverageReporter.cs b/Source/DafnyDriver/CoverageReporter.cs
index 37d15c17168..205c12ebd0f 100644
--- a/Source/DafnyDriver/CoverageReporter.cs
+++ b/Source/DafnyDriver/CoverageReporter.cs
@@ -263,7 +263,7 @@ private void CreateIndexFile(CoverageReport report, Dictionary<Uri, string> sour
           module.FullName
         });
 
-        var moduleRange = module.RangeToken.ToDafnyRange();
+        var moduleRange = module.Origin.ToDafnyRange();
         body.Last().AddRange(coverageLabels
           .Where(label => label != CoverageLabel.None && label != CoverageLabel.NotApplicable)
           .Select(label => report.CoverageSpansForFile(sourceFile)
diff --git a/Source/DafnyDriver/DafnyDoc.cs b/Source/DafnyDriver/DafnyDoc.cs
index 27027709027..44b3c1ccae2 100644
--- a/Source/DafnyDriver/DafnyDoc.cs
+++ b/Source/DafnyDriver/DafnyDoc.cs
@@ -579,7 +579,7 @@ public Info ExecutableInfo(bool register, MemberDecl m, TopLevelDeclWithMembers
   }
 
   public string ExpressionAsSource(Expression e) {
-    return e.RangeToken.PrintOriginal();
+    return e.Origin.PrintOriginal();
   }
 
   public Info TypeInfo(bool register, TopLevelDecl t, ModuleDefinition module, Info owner) {
diff --git a/Source/DafnyLanguageServer.Test/Lookup/HoverVerificationTest.cs b/Source/DafnyLanguageServer.Test/Lookup/HoverVerificationTest.cs
index 64a9c4bb905..0d1d7713b6b 100644
--- a/Source/DafnyLanguageServer.Test/Lookup/HoverVerificationTest.cs
+++ b/Source/DafnyLanguageServer.Test/Lookup/HoverVerificationTest.cs
@@ -133,7 +133,7 @@ await AssertVerificationHoverMatches(documentItem, (2, 12),
 This is the only assertion in [batch](???) #??? of ??? in method `f`  
 [Batch](???) #??? resource usage: ??? RU"
       );
-      await AssertVerificationHoverMatches(documentItem, (0, 36),
+      await AssertVerificationHoverMatches(documentItem, (0, 29),
         @"**Verification performance metrics for method `f`**:
 
 - Total resource usage: ??? RU  
diff --git a/Source/DafnyLanguageServer.Test/Lookup/WorkspaceSymbolTest.cs b/Source/DafnyLanguageServer.Test/Lookup/WorkspaceSymbolTest.cs
index 5bc0f9ba29f..759a820474e 100644
--- a/Source/DafnyLanguageServer.Test/Lookup/WorkspaceSymbolTest.cs
+++ b/Source/DafnyLanguageServer.Test/Lookup/WorkspaceSymbolTest.cs
@@ -69,8 +69,6 @@ trait TestTrait {}
 
 predicate TestPredicate() { false }", "test-workspace-symbols.dfy", false);
 
-      await client.OpenDocumentAndWaitAsync(documentItem, CancellationToken);
-
       var testSymbols = new List<string> {
         "TestClass",
         "TestModule",
diff --git a/Source/DafnyLanguageServer.Test/Synchronization/DeclarationLocationMigrationTest.cs b/Source/DafnyLanguageServer.Test/Synchronization/DeclarationLocationMigrationTest.cs
index bddcc5ba657..67139c357a5 100644
--- a/Source/DafnyLanguageServer.Test/Synchronization/DeclarationLocationMigrationTest.cs
+++ b/Source/DafnyLanguageServer.Test/Synchronization/DeclarationLocationMigrationTest.cs
@@ -286,7 +286,7 @@ var a
       Assert.Equal(new Range((4, 0), (7, 0)), bLocation.Declaration);
       Assert.True(TryFindSymbolDeclarationByName(document, "y", out var yLocation));
       Assert.Equal(new Range((6, 6), (6, 7)), yLocation.Name);
-      Assert.Equal(new Range((6, 6), (6, 7)), yLocation.Declaration);
+      Assert.Equal(new Range((6, 2), (6, 12)), yLocation.Declaration);
     }
 
     [Fact]
diff --git a/Source/DafnyLanguageServer.Test/Various/DiagnosticMigrationTest.cs b/Source/DafnyLanguageServer.Test/Various/DiagnosticMigrationTest.cs
index 4119cf4dff3..152c502a1e0 100644
--- a/Source/DafnyLanguageServer.Test/Various/DiagnosticMigrationTest.cs
+++ b/Source/DafnyLanguageServer.Test/Various/DiagnosticMigrationTest.cs
@@ -54,12 +54,13 @@ public async Task ResolutionDiagnosticsAreRemovedWhenRangeIsDeleted() {
 
   [Fact]
   public async Task ResolutionDiagnosticsAreKeptWhenNonEdgeCrossingChangesAreMade() {
-    var documentItem = CreateTestDocument(@"method GetConstant() returns (x: int) 
+    var documentItem = CreateTestDocument(@"
+method GetConstant() returns (x: int) 
   ensures x == 2 
   { 
     x := 1;
     return;
-  }");
+  }".TrimStart());
     client.OpenDocument(documentItem);
     var verificationDiagnostics = await GetLastDiagnostics(documentItem);
     Assert.Single(verificationDiagnostics);
@@ -101,7 +102,7 @@ public async Task ResolutionDiagnosticsAreKeptWhenNonEdgeCrossingChangesAreMade(
     Assert.Equal(verificationDiagnostics.Length, resolutionDiagnostics.Length);
     Assert.Equal(IdeState.OutdatedPrefix + verificationDiagnostics[0].Message, resolutionDiagnostics[0].Message);
     Assert.Equal(verificationDiagnostics[0].RelatedInformation, resolutionDiagnostics[0].RelatedInformation);
-    Assert.Equal(new Range(4, 7, 4, 13), resolutionDiagnostics[0].Range);
+    Assert.Equal(new Range(4, 7, 4, 14), resolutionDiagnostics[0].Range);
   }
 
   [Fact]
diff --git a/Source/DafnyLanguageServer/Handlers/DafnyCompletionHandler.cs b/Source/DafnyLanguageServer/Handlers/DafnyCompletionHandler.cs
index 5d188ea4138..56080190c1b 100644
--- a/Source/DafnyLanguageServer/Handlers/DafnyCompletionHandler.cs
+++ b/Source/DafnyLanguageServer/Handlers/DafnyCompletionHandler.cs
@@ -108,7 +108,7 @@ private string GetLastTwoCharactersBeforePositionIncluded(TextBuffer text, Dafny
 
       private bool IsDotExpression() {
         var node = state.Program.FindNode<INode>(request.TextDocument.Uri.ToUri(), request.Position.ToDafnyPosition());
-        return node?.RangeToken.EndToken.val == ".";
+        return node?.Origin.EndToken.val == ".";
       }
 
       private bool IsAtAttribute() {
diff --git a/Source/DafnyLanguageServer/Handlers/DafnyDocumentSymbolHandler.cs b/Source/DafnyLanguageServer/Handlers/DafnyDocumentSymbolHandler.cs
index e4db375af42..dc4ae7e7ad9 100644
--- a/Source/DafnyLanguageServer/Handlers/DafnyDocumentSymbolHandler.cs
+++ b/Source/DafnyLanguageServer/Handlers/DafnyDocumentSymbolHandler.cs
@@ -59,7 +59,7 @@ private IEnumerable<DocumentSymbol> FromSymbol(ISymbol symbol) {
         return children;
       }
 
-      var range = symbol.RangeToken.ToLspRange();
+      var range = symbol.Origin.ToLspRange();
       return new DocumentSymbol[] {
         new() {
           Children = children,
@@ -67,7 +67,7 @@ private IEnumerable<DocumentSymbol> FromSymbol(ISymbol symbol) {
           Detail = documentation,
           Range = range,
           Kind = symbol.Kind.Value,
-          SelectionRange = symbol.NavigationToken == Token.NoToken ? range : symbol.NavigationToken.ToRange().ToLspRange()
+          SelectionRange = symbol.NavigationToken == Token.NoToken ? range : symbol.NavigationToken.ToLspRange()
         }
       };
     }
diff --git a/Source/DafnyLanguageServer/Handlers/DafnyHoverHandler.cs b/Source/DafnyLanguageServer/Handlers/DafnyHoverHandler.cs
index 52a9900a318..9b6fc115f24 100644
--- a/Source/DafnyLanguageServer/Handlers/DafnyHoverHandler.cs
+++ b/Source/DafnyLanguageServer/Handlers/DafnyHoverHandler.cs
@@ -73,7 +73,7 @@ protected override HoverRegistrationOptions CreateRegistrationOptions(HoverCapab
       } else {
         // If we hover over a usage, display the information of the declaration
         symbol = declarationOrUsage as ISymbol;
-        if (symbol != null && !symbol.NavigationToken.ToRange().ToLspRange().Contains(request.Position)) {
+        if (symbol != null && !symbol.NavigationToken.ToLspRange().Contains(request.Position)) {
           symbol = null;
         }
       }
diff --git a/Source/DafnyLanguageServer/Language/GhostStateDiagnosticCollector.cs b/Source/DafnyLanguageServer/Language/GhostStateDiagnosticCollector.cs
index 8210a99a494..0a491705ea8 100644
--- a/Source/DafnyLanguageServer/Language/GhostStateDiagnosticCollector.cs
+++ b/Source/DafnyLanguageServer/Language/GhostStateDiagnosticCollector.cs
@@ -85,7 +85,7 @@ private bool IsGhostStatementToMark(Statement statement) {
       private static Range GetRange(Statement statement) {
         return statement switch {
           AssignStatement updateStatement => GetRange(updateStatement),
-          _ => CreateRange(statement.RangeToken.StartToken, statement.RangeToken.EndToken)
+          _ => CreateRange(statement.Origin.StartToken, statement.Origin.EndToken)
         };
       }
 
@@ -100,7 +100,7 @@ private static Range GetRange(AssignStatement updateStatement) {
         } else {
           startToken = updateStatement.Tok;
         }
-        return CreateRange(startToken, updateStatement.RangeToken.EndToken);
+        return CreateRange(startToken, updateStatement.Origin.EndToken);
       }
 
       private static IOrigin GetStartTokenFromResolvedStatement(Statement resolvedStatement) {
diff --git a/Source/DafnyLanguageServer/Language/ImplicitFailingAssertionCodeActionProvider.cs b/Source/DafnyLanguageServer/Language/ImplicitFailingAssertionCodeActionProvider.cs
index 998da220765..3f67298ffba 100644
--- a/Source/DafnyLanguageServer/Language/ImplicitFailingAssertionCodeActionProvider.cs
+++ b/Source/DafnyLanguageServer/Language/ImplicitFailingAssertionCodeActionProvider.cs
@@ -25,7 +25,7 @@ public ImplicitFailingAssertionCodeActionProvider(ILogger<DafnyCodeActionHandler
   }
 
   protected static List<INode>? FindInnermostNodeIntersecting(INode node, Range range) {
-    if (node.StartToken.line > 0 && !node.RangeToken.ToLspRange().Intersects(range)) {
+    if (node.StartToken.line > 0 && !node.Origin.ToLspRange().Intersects(range)) {
       return null;
     }
 
diff --git a/Source/DafnyLanguageServer/Language/Symbols/ScopeSymbol.cs b/Source/DafnyLanguageServer/Language/Symbols/ScopeSymbol.cs
index 2ce19663a2e..a2a1ba7afae 100644
--- a/Source/DafnyLanguageServer/Language/Symbols/ScopeSymbol.cs
+++ b/Source/DafnyLanguageServer/Language/Symbols/ScopeSymbol.cs
@@ -12,8 +12,8 @@ public class ScopeSymbol : Symbol, ILocalizableSymbol {
 
     public ScopeSymbol(ILegacySymbol? scope, INode region) : base(scope, string.Empty) {
       Node = region;
-      BodyStartToken = region.RangeToken.StartToken;
-      BodyEndToken = region.RangeToken.EndToken;
+      BodyStartToken = region.Origin.StartToken;
+      BodyEndToken = region.Origin.EndToken;
     }
 
     public override TResult Accept<TResult>(ISymbolVisitor<TResult> visitor) {
diff --git a/Source/DafnyLanguageServer/Language/Symbols/SymbolTableFactory.cs b/Source/DafnyLanguageServer/Language/Symbols/SymbolTableFactory.cs
index b712ae5c33b..e10f1e9e19d 100644
--- a/Source/DafnyLanguageServer/Language/Symbols/SymbolTableFactory.cs
+++ b/Source/DafnyLanguageServer/Language/Symbols/SymbolTableFactory.cs
@@ -311,8 +311,8 @@ public Unit Visit(ModuleSymbol moduleSymbol) {
         RegisterLocation(
           moduleSymbol,
           moduleSymbol.Declaration.tok,
-          moduleSymbol.Declaration.tok.GetLspRange(),
-          moduleSymbol.Declaration.RangeToken.ToLspRange()
+          moduleSymbol.Declaration.NameNode.Origin.GetLspRange(),
+          moduleSymbol.Declaration.Origin.ToLspRange()
         );
         VisitChildren(moduleSymbol);
         return Unit.Value;
@@ -330,9 +330,9 @@ private Unit VisitTypeSymbol<TNode>(TypeWithMembersSymbolBase<TNode> typeSymbol)
         cancellationToken.ThrowIfCancellationRequested();
         RegisterLocation(
           typeSymbol,
-          typeSymbol.Declaration.tok,
-          typeSymbol.Declaration.tok.GetLspRange(),
-          new Range(typeSymbol.Declaration.RangeToken.StartToken.GetLspPosition(), typeSymbol.Declaration.RangeToken.EndToken.GetLspPosition())
+          typeSymbol.Declaration.Origin,
+          typeSymbol.Declaration.NameNode.Origin.GetLspRange(),
+          new Range(typeSymbol.Declaration.Origin.StartToken.GetLspPosition(), typeSymbol.Declaration.Origin.EndToken.GetLspPosition())
         );
         VisitChildren(typeSymbol);
         return Unit.Value;
@@ -342,9 +342,9 @@ public Unit Visit(ValueTypeSymbol valueTypeSymbol) {
         cancellationToken.ThrowIfCancellationRequested();
         RegisterLocation(
           valueTypeSymbol,
-          valueTypeSymbol.Declaration.tok,
-          valueTypeSymbol.Declaration.tok.GetLspRange(),
-          new Range(valueTypeSymbol.Declaration.RangeToken.StartToken.GetLspPosition(), valueTypeSymbol.Declaration.RangeToken.EndToken.GetLspPosition())
+          valueTypeSymbol.Declaration.Origin,
+          valueTypeSymbol.Declaration.NameNode.Origin.GetLspRange(),
+          new Range(valueTypeSymbol.Declaration.Origin.StartToken.GetLspPosition(), valueTypeSymbol.Declaration.Origin.EndToken.GetLspPosition())
         );
         VisitChildren(valueTypeSymbol);
         return Unit.Value;
@@ -354,10 +354,10 @@ public Unit Visit(FieldSymbol fieldSymbol) {
         cancellationToken.ThrowIfCancellationRequested();
         RegisterLocation(
           fieldSymbol,
-          fieldSymbol.Declaration.tok,
-          fieldSymbol.Declaration.tok.GetLspRange(),
+          fieldSymbol.Declaration.Origin,
+          fieldSymbol.Declaration.NameNode.Origin.GetLspRange(),
           // BodyEndToken always returns Token.NoToken
-          fieldSymbol.Declaration.tok.GetLspRange()
+          fieldSymbol.Declaration.Origin.GetLspRange()
         );
         VisitChildren(fieldSymbol);
         return Unit.Value;
@@ -368,7 +368,7 @@ public Unit Visit(FunctionSymbol functionSymbol) {
         RegisterLocation(
           functionSymbol,
           functionSymbol.Declaration.tok,
-          functionSymbol.Declaration.tok.GetLspRange(),
+          functionSymbol.Declaration.NameNode.Origin.GetLspRange(),
           GetDeclarationRange(functionSymbol.Declaration)
         );
         VisitChildren(functionSymbol);
@@ -380,7 +380,7 @@ public Unit Visit(MethodSymbol methodSymbol) {
         RegisterLocation(
           methodSymbol,
           methodSymbol.Declaration.tok,
-          methodSymbol.Declaration.tok.GetLspRange(),
+          methodSymbol.Declaration.NameNode.Origin.GetLspRange(),
           GetDeclarationRange(methodSymbol.Declaration)
         );
         VisitChildren(methodSymbol);
@@ -388,9 +388,9 @@ public Unit Visit(MethodSymbol methodSymbol) {
       }
 
       private static Range GetDeclarationRange(Declaration declaration) {
-        return declaration.RangeToken == RangeToken.NoToken
+        return declaration.Origin == RangeToken.NoToken
           ? declaration.tok.GetLspRange()
-          : new Range(declaration.RangeToken.StartToken.GetLspPosition(), declaration.RangeToken.EndToken.GetLspPosition());
+          : new Range(declaration.Origin.StartToken.GetLspPosition(), declaration.Origin.EndToken.GetLspPosition());
       }
 
       public Unit Visit(VariableSymbol variableSymbol) {
@@ -398,7 +398,7 @@ public Unit Visit(VariableSymbol variableSymbol) {
         RegisterLocation(
           variableSymbol,
           variableSymbol.Declaration.Tok,
-          variableSymbol.Declaration.Tok.GetLspRange(),
+          variableSymbol.Declaration.Origin.Center.GetLspRange(),
           variableSymbol.Declaration.Tok.GetLspRange()
         );
         VisitChildren(variableSymbol);
@@ -424,13 +424,13 @@ private void VisitChildren(ILegacySymbol symbol) {
         }
       }
 
-      private void RegisterLocation(ILegacySymbol symbol, IOrigin token, Range name, Range declaration) {
-        if (token.Filepath != null) {
+      private void RegisterLocation(ILegacySymbol symbol, IOrigin origin, Range name, Range declaration) {
+        if (origin.Filepath != null) {
           // The filename is null if we have a default or System based symbol. This is also reflected by the ranges being usually -1.
           var locationsForUri =
-            Locations.GetValueOrDefault(token.Uri) ?? new Dictionary<ILegacySymbol, SymbolLocation>();
-          Locations = Locations.SetItem(token.Uri, locationsForUri);
-          locationsForUri.Add(symbol, new SymbolLocation(token.Uri, name, declaration));
+            Locations.GetValueOrDefault(origin.Uri) ?? new Dictionary<ILegacySymbol, SymbolLocation>();
+          Locations = Locations.SetItem(origin.Uri, locationsForUri);
+          locationsForUri.Add(symbol, new SymbolLocation(origin.Uri, name, declaration));
         }
       }
     }
diff --git a/Source/DafnyLanguageServer/Plugins/DafnyCodeActionHelpers.cs b/Source/DafnyLanguageServer/Plugins/DafnyCodeActionHelpers.cs
index b4abba867fa..4d7b62f2a24 100644
--- a/Source/DafnyLanguageServer/Plugins/DafnyCodeActionHelpers.cs
+++ b/Source/DafnyLanguageServer/Plugins/DafnyCodeActionHelpers.cs
@@ -133,10 +133,10 @@ private static (RangeToken? beforeEndBrace, string indentationExtra, string inde
   /// <param name="line">The line of the opening brace</param>
   /// <param name="col">The column of the opening brace</param>
   /// <returns>The token of a matching closing brace, typically the `ÈndTok` of a BlockStmt</returns>
-  private static IOrigin? GetMatchingEndToken(Node program, Uri documentUri, int line, int col) {
+  private static Token? GetMatchingEndToken(Node program, Uri documentUri, int line, int col) {
     // Look in methods for BlockStmt with the IToken as opening brace
     // Return the EndTok of them.
-    IOrigin? tokenFound = null;
+    Token? tokenFound = null;
     program.Visit((INode n) => {
       if (tokenFound != null) {
         return false;
@@ -167,11 +167,11 @@ private static (RangeToken? beforeEndBrace, string indentationExtra, string inde
   /// returns the closing brace token, else null.
   /// Visit substatements recursively
   /// </summary>
-  private static IOrigin? GetMatchingEndToken(int line, int col, Statement stmt) {
+  private static Token? GetMatchingEndToken(int line, int col, Statement stmt) {
     // Look in methods for BlockStmt with the IToken as opening brace
     // Return the EndTok of them.
     if (stmt is BlockStmt blockStmt && blockStmt.Tok.line == line && blockStmt.Tok.col == col) {
-      return blockStmt.RangeToken.EndToken;
+      return blockStmt.Origin.EndToken;
     }
 
     foreach (var subStmt in stmt.SubStatements) {
diff --git a/Source/DafnyLanguageServer/Plugins/DafnyCodeActionProvider.cs b/Source/DafnyLanguageServer/Plugins/DafnyCodeActionProvider.cs
index 573bb05cfb1..e0a796b88d6 100644
--- a/Source/DafnyLanguageServer/Plugins/DafnyCodeActionProvider.cs
+++ b/Source/DafnyLanguageServer/Plugins/DafnyCodeActionProvider.cs
@@ -34,10 +34,10 @@ public abstract class DafnyCodeActionProvider {
 
   // When building DafnyCodeActionEdit (what DafnyCodeAction return),
   // use this to create ranges suitable for insertion
-  protected static RangeToken InsertBefore(IOrigin tok) {
+  protected static RangeToken InsertBefore(Token tok) {
     return new RangeToken(tok, null);
   }
-  protected static RangeToken InsertAfter(IOrigin tok) {
+  protected static RangeToken InsertAfter(Token tok) {
     return new RangeToken(new Token(tok.line, tok.col + tok.val.Length) {
       pos = tok.pos + tok.val.Length,
     }, null);
diff --git a/Source/DafnyLanguageServer/Util/PathExtensions.cs b/Source/DafnyLanguageServer/Util/PathExtensions.cs
index ce6275b84bb..7cfc64de825 100644
--- a/Source/DafnyLanguageServer/Util/PathExtensions.cs
+++ b/Source/DafnyLanguageServer/Util/PathExtensions.cs
@@ -53,7 +53,7 @@ public static bool IsEntryDocument(this Dafny.Program program, DocumentUri docum
     /// <returns>The uri of the document where the token is located.</returns>
     public static DocumentUri GetDocumentUri(this Boogie.IToken token) {
       while (token is RefinementOrigin refinementToken) {
-        token = refinementToken.WrappedToken;
+        token = refinementToken.WrappedOrigin;
       }
 
       return DocumentUri.From(((IOrigin)token).Uri);
diff --git a/Source/DafnyLanguageServer/Workspace/GutterIconAndHoverVerificationDetailsManager.cs b/Source/DafnyLanguageServer/Workspace/GutterIconAndHoverVerificationDetailsManager.cs
index 0809c17b07f..9b4796817fe 100644
--- a/Source/DafnyLanguageServer/Workspace/GutterIconAndHoverVerificationDetailsManager.cs
+++ b/Source/DafnyLanguageServer/Workspace/GutterIconAndHoverVerificationDetailsManager.cs
@@ -109,7 +109,7 @@ void AddAndPossiblyMigrateVerificationTree(VerificationTree verificationTree) {
                 Attributes.Contains(member.Attributes, "only"));
               AddAndPossiblyMigrateVerificationTree(verificationTree);
               if (member is Function { ByMethodBody: { } } function) {
-                var verificationTreeRangeByMethod = function.ByMethodBody.RangeToken.ToLspRange();
+                var verificationTreeRangeByMethod = function.ByMethodBody.Origin.ToLspRange();
                 var verificationTreeByMethod = new TopLevelDeclMemberVerificationTree(
                   "by method part of function",
                   member.Name,
diff --git a/Source/DafnyLanguageServer/Workspace/Notifications/VerificationDiagnosticsParams.cs b/Source/DafnyLanguageServer/Workspace/Notifications/VerificationDiagnosticsParams.cs
index d63b3a0c4c4..6bb84cd4707 100644
--- a/Source/DafnyLanguageServer/Workspace/Notifications/VerificationDiagnosticsParams.cs
+++ b/Source/DafnyLanguageServer/Workspace/Notifications/VerificationDiagnosticsParams.cs
@@ -369,7 +369,7 @@ private static Range ComputeRange(INode node, Uri uri) {
       if (node is not Program program) {
         return new Range(0, 0, -1, 0);
       }
-      var end = program.Files.FirstOrDefault(f => f.RangeToken.Uri == uri)?.EndToken ?? Token.NoToken;
+      var end = program.Files.FirstOrDefault(f => f.Origin.Uri == uri)?.EndToken ?? Token.NoToken;
       while (end.Next != null) {
         end = end.Next;
       }
@@ -608,7 +608,7 @@ private AssertionVerificationTree WithImmediatelyRelatedChanges() {
       if (counterExample is ReturnCounterexample returnCounterexample) {
         tok = returnCounterexample.FailingReturn.tok;
         if (tok.filename == assertion.tok.filename) {
-          result.Add(returnCounterexample.FailingReturn.tok.GetLspRange());
+          result.Add(BoogieGenerator.ToDafnyToken(true, returnCounterexample.FailingReturn.tok).Center.GetLspRange());
         }
       }
 
diff --git a/Source/DafnyLanguageServer/Workspace/ProjectManager.cs b/Source/DafnyLanguageServer/Workspace/ProjectManager.cs
index fe84023846e..a3390f69cdc 100644
--- a/Source/DafnyLanguageServer/Workspace/ProjectManager.cs
+++ b/Source/DafnyLanguageServer/Workspace/ProjectManager.cs
@@ -352,8 +352,8 @@ IntervalTree<Position, Position> GetTree(Uri uri) {
       foreach (var canVerify in verifiables) {
         if (canVerify.Tok.Uri == uri) {
           intervalTree.Add(
-            canVerify.RangeToken.StartToken.GetLspPosition(),
-            canVerify.RangeToken.EndToken.GetLspPosition(true),
+            canVerify.Origin.StartToken.GetLspPosition(),
+            canVerify.Origin.EndToken.GetLspPosition(true),
             canVerify.NavigationToken.GetLspPosition());
         }
       }
diff --git a/Source/DafnyLanguageServer/Workspace/SymbolTable.cs b/Source/DafnyLanguageServer/Workspace/SymbolTable.cs
index 7f6b3674f48..c6c71187e15 100644
--- a/Source/DafnyLanguageServer/Workspace/SymbolTable.cs
+++ b/Source/DafnyLanguageServer/Workspace/SymbolTable.cs
@@ -17,7 +17,8 @@ public class SymbolTable {
   public static SymbolTable CreateFrom(ILogger logger, Program program, CancellationToken cancellationToken) {
     var visited = program.Visit(a => true, b => { });
 
-    var references = visited.OfType<IHasReferences>().Where(v => !AutoGeneratedOrigin.Is(v.NavigationToken))
+    var notGenerated = visited.OfType<IHasReferences>().Where(v => !AutoGeneratedOrigin.Is(v.NavigationToken));
+    var references = notGenerated
       .SelectMany(r => {
         var usages = r.GetReferences();
         if (usages == null) {
diff --git a/Source/DafnyTestGeneration/Inlining/AddByMethodRewriter.cs b/Source/DafnyTestGeneration/Inlining/AddByMethodRewriter.cs
index 44fc0264258..e283ce09437 100644
--- a/Source/DafnyTestGeneration/Inlining/AddByMethodRewriter.cs
+++ b/Source/DafnyTestGeneration/Inlining/AddByMethodRewriter.cs
@@ -47,9 +47,9 @@ private static Attributes RemoveOpaqueAttr(Attributes attributes, Cloner cloner)
     if (attributes is UserSuppliedAttributes) {
       var usa = (UserSuppliedAttributes)attributes;
       return new UserSuppliedAttributes(
-        cloner.Tok(usa.tok),
-        cloner.Tok(usa.OpenBrace),
-        cloner.Tok(usa.CloseBrace),
+        cloner.Origin(usa.tok),
+        cloner.Origin(usa.OpenBrace),
+        cloner.Origin(usa.CloseBrace),
         attributes.Args.ConvertAll(cloner.CloneExpr),
         RemoveOpaqueAttr(attributes.Prev, cloner));
     }
@@ -68,10 +68,10 @@ private void AddByMethod(Function func) {
       return;
     }
 
-    var returnStatement = new ReturnStmt(func.Body.RangeToken,
+    var returnStatement = new ReturnStmt(func.Body.Origin,
       new List<AssignmentRhs> { new ExprRhs(new Cloner().CloneExpr(func.Body)) });
     func.ByMethodBody = new BlockStmt(
-      func.Body.RangeToken,
+      func.Body.Origin,
       new List<Statement> { returnStatement });
     func.ByMethodTok = func.Body.tok;
   }
diff --git a/Source/DafnyTestGeneration/Inlining/FunctionCallToMethodCallRewriter.cs b/Source/DafnyTestGeneration/Inlining/FunctionCallToMethodCallRewriter.cs
index fdd55f878bb..bb81cee0a80 100644
--- a/Source/DafnyTestGeneration/Inlining/FunctionCallToMethodCallRewriter.cs
+++ b/Source/DafnyTestGeneration/Inlining/FunctionCallToMethodCallRewriter.cs
@@ -71,7 +71,7 @@ public override Statement CloneStmt(Statement stmt, bool isReference) {
           funcCallExpr.Function.ByMethodDecl.Name);
         memberSelectExpr.Member = funcCallExpr.Function.ByMethodDecl;
         memberSelectExpr.TypeApplicationJustMember = funcCallExpr.TypeApplication_JustFunction;
-        newResolvedStmts.Add(new CallStmt(stmt.RangeToken,
+        newResolvedStmts.Add(new CallStmt(stmt.Origin,
           updateStmt.Lhss.Select(lhs => CloneExpr(lhs.Resolved)).ToList(), memberSelectExpr,
           funcCallExpr.Args.ConvertAll(e => CloneExpr(e.Resolved))));
       } else {
diff --git a/Source/DafnyTestGeneration/Inlining/RemoveShortCircuitRewriter.cs b/Source/DafnyTestGeneration/Inlining/RemoveShortCircuitRewriter.cs
index fb6f87290dd..4b908867aa4 100644
--- a/Source/DafnyTestGeneration/Inlining/RemoveShortCircuitRewriter.cs
+++ b/Source/DafnyTestGeneration/Inlining/RemoveShortCircuitRewriter.cs
@@ -87,7 +87,7 @@ public override BlockStmt CloneBlockStmt(BlockStmt blockStatement) {
     foreach (var statement in blockStatement.Body) {
       newBody.AddRange(ProcessStmt(statement));
     }
-    return new BlockStmt(blockStatement.RangeToken, newBody);
+    return new BlockStmt(blockStatement.Origin, newBody);
   }
 
   public override DividedBlockStmt CloneDividedBlockStmt(DividedBlockStmt blockStatement) {
@@ -101,7 +101,7 @@ public override DividedBlockStmt CloneDividedBlockStmt(DividedBlockStmt blockSta
       var processed = ProcessStmt(statement);
       newBodyProper.AddRange(processed);
     }
-    return new DividedBlockStmt(blockStatement.RangeToken, newBodyInit, blockStatement.SeparatorTok, newBodyProper);
+    return new DividedBlockStmt(blockStatement.Origin, newBodyInit, blockStatement.SeparatorTok, newBodyProper);
   }
 
   private List<Statement> ProcessStmt(Statement statement) {
@@ -199,11 +199,11 @@ private Statement CloneIfStmt(IfStmt ifStatement) {
     if (ifStatement.Els != null) {
       els = ProcessStmtToStmt(ifStatement.Els);
     }
-    return new IfStmt(ifStatement.RangeToken, ifStatement.IsBindingGuard, guard, thn, els, ifStatement.Attributes);
+    return new IfStmt(ifStatement.Origin, ifStatement.IsBindingGuard, guard, thn, els, ifStatement.Attributes);
   }
 
   private Statement CloneUpdateStmt(AssignStatement updateStatement) {
-    return new AssignStatement(updateStatement.RangeToken, CloneExpressionList(updateStatement.Lhss), CloneRhss(updateStatement.Rhss, true));
+    return new AssignStatement(updateStatement.Origin, CloneExpressionList(updateStatement.Lhss), CloneRhss(updateStatement.Rhss, true));
   }
 
   private Statement CloneAssignOrReturnStmt(AssignOrReturnStmt assignOrReturnStmt) {
@@ -215,16 +215,16 @@ private Statement CloneAssignOrReturnStmt(AssignOrReturnStmt assignOrReturnStmt)
       }
       rhs = new ExprRhs(noCircuits.expr, assignOrReturnStmt.Rhs.Attributes);
     }
-    return new AssignOrReturnStmt(assignOrReturnStmt.RangeToken, CloneExpressionList(assignOrReturnStmt.Lhss), rhs,
+    return new AssignOrReturnStmt(assignOrReturnStmt.Origin, CloneExpressionList(assignOrReturnStmt.Lhss), rhs,
       assignOrReturnStmt.KeywordToken, CloneRhss(assignOrReturnStmt.Rhss, true));
   }
 
   private Statement CloneReturnStmt(ReturnStmt returnStatement) {
-    return new ReturnStmt(returnStatement.RangeToken, CloneRhss(returnStatement.Rhss, false));
+    return new ReturnStmt(returnStatement.Origin, CloneRhss(returnStatement.Rhss, false));
   }
 
   private Statement CloneCallStmt(CallStmt callStmt) {
-    return new CallStmt(callStmt.RangeToken, CloneExpressionList(callStmt.Lhs), callStmt.MethodSelect, CloneExpressionList(callStmt.Args));
+    return new CallStmt(callStmt.Origin, CloneExpressionList(callStmt.Lhs), callStmt.MethodSelect, CloneExpressionList(callStmt.Args));
   }
 
   private Statement CloneNestedMatchStmt(NestedMatchStmt nestedMatchStatement) {
@@ -232,13 +232,13 @@ private Statement CloneNestedMatchStmt(NestedMatchStmt nestedMatchStatement) {
     newStmtStack.Last().AddRange(noCircuits.stmts);
     var newCases = new List<NestedMatchCaseStmt>();
     foreach (var nestedMatchCase in nestedMatchStatement.Cases) {
-      newCases.Add(new NestedMatchCaseStmt(nestedMatchCase.RangeToken, nestedMatchCase.Pat, ProcessStmtList(nestedMatchCase.Body)));
+      newCases.Add(new NestedMatchCaseStmt(nestedMatchCase.Origin, nestedMatchCase.Pat, ProcessStmtList(nestedMatchCase.Body)));
     }
-    return new NestedMatchStmt(nestedMatchStatement.RangeToken, noCircuits.expr, newCases, nestedMatchStatement.UsesOptionalBraces, nestedMatchStatement.Attributes);
+    return new NestedMatchStmt(nestedMatchStatement.Origin, noCircuits.expr, newCases, nestedMatchStatement.UsesOptionalBraces, nestedMatchStatement.Attributes);
   }
 
   private Statement ClonePrintStmt(PrintStmt printStatement) {
-    return new PrintStmt(printStatement.RangeToken, CloneExpressionList(printStatement.Args));
+    return new PrintStmt(printStatement.Origin, CloneExpressionList(printStatement.Args));
   }
 
   private Statement CloneWhileStmt(WhileStmt whileStmt) {
@@ -246,7 +246,7 @@ private Statement CloneWhileStmt(WhileStmt whileStmt) {
     newStmtStack.Last().AddRange(noCircuits.stmts);
     var newBody = CloneBlockStmt(whileStmt.Body);
     newBody.Body.AddRange(ProcessStmtList(noCircuits.stmts.Where(stmt => stmt is not VarDeclStmt).ToList()));
-    return new WhileStmt(whileStmt.RangeToken, noCircuits.expr, whileStmt.Invariants, whileStmt.Decreases, whileStmt.Mod, newBody);
+    return new WhileStmt(whileStmt.Origin, noCircuits.expr, whileStmt.Invariants, whileStmt.Decreases, whileStmt.Mod, newBody);
   }
 
   private Statement CloneForLoopStmt(ForLoopStmt forLoopStmt) {
@@ -255,7 +255,7 @@ private Statement CloneForLoopStmt(ForLoopStmt forLoopStmt) {
     var end = RemoveShortCircuit(forLoopStmt.End, false);
     newStmtStack.Last().AddRange(end.stmts);
     var newBody = CloneBlockStmt(forLoopStmt.Body);
-    return new ForLoopStmt(forLoopStmt.RangeToken, forLoopStmt.LoopIndex, start.expr, end.expr, forLoopStmt.GoingUp,
+    return new ForLoopStmt(forLoopStmt.Origin, forLoopStmt.LoopIndex, start.expr, end.expr, forLoopStmt.GoingUp,
       forLoopStmt.Invariants, forLoopStmt.Decreases, forLoopStmt.Mod, newBody, forLoopStmt.Attributes);
   }
 
@@ -264,7 +264,7 @@ private Statement ProcessStmtToStmt(Statement statement) {
     if (statements.Count == 1) {
       return statements[0];
     }
-    return new BlockStmt(statement.RangeToken, statements);
+    return new BlockStmt(statement.Origin, statements);
   }
 
   private List<Statement> ProcessStmtList(List<Statement> statements) {
@@ -323,7 +323,7 @@ private Expression CreateIf(string tmpVarName, Type typ, Expression initialExpr,
         new List<AssignmentRhs> { new ExprRhs(elseExpr) })
       : null;
     var ifStmt = new IfStmt(new RangeToken(original.StartToken, original.StartToken), false, testExpr,
-      new BlockStmt(thenStmt.RangeToken, new List<Statement> { thenStmt }), elseStmt);
+      new BlockStmt(thenStmt.Origin, new List<Statement> { thenStmt }), elseStmt);
     newStmtStack.Last().Add(ifStmt);
     return identifierExpr;
   }
@@ -363,7 +363,7 @@ public override Expression CloneExpr(Expression expr) {
           Expression.CreateBoolLiteral(binaryExpr.E1.EndToken, true), binaryExpr);
       case StmtExpr stmtExpr:
         newStmtStack.Last().Add(varDecl);
-        assignStatement = new AssignStatement(stmtExpr.E.RangeToken, new List<Expression> { identifierExpr },
+        assignStatement = new AssignStatement(stmtExpr.E.Origin, new List<Expression> { identifierExpr },
           new List<AssignmentRhs> { new ExprRhs(stmtExpr.E) });
         var stmtBlockUpdate = new BlockStmt(new RangeToken(stmtExpr.S.StartToken, stmtExpr.E.EndToken), new List<Statement>());
         stmtBlockUpdate.Body.Add(stmtExpr.S);
@@ -378,26 +378,26 @@ public override Expression CloneExpr(Expression expr) {
             new List<AssignmentRhs> { new ExprRhs(c.Body) });
           caseStmts.Add(new NestedMatchCaseStmt(new RangeToken(c.StartToken, c.StartToken), c.Pat, new List<Statement> { assignStatement }));
         }
-        var matchStmt = new NestedMatchStmt(matchExpr.RangeToken, matchExpr.Source, caseStmts, false, matchExpr.Attributes);
+        var matchStmt = new NestedMatchStmt(matchExpr.Origin, matchExpr.Source, caseStmts, false, matchExpr.Attributes);
         newStmtStack.Last().Add(matchStmt);
         return identifierExpr;
       case LetOrFailExpr { Lhs: not null } letOrFailExpr:
         newStmtStack.Last().Add(varDecl);
         var boundIdentifierExpr = new IdentifierExpr(letOrFailExpr.Rhs.StartToken, letOrFailExpr.Lhs.Var.Name);
-        var assignOrReturn = new AssignOrReturnStmt(letOrFailExpr.Rhs.RangeToken, new List<Expression> { boundIdentifierExpr }, new ExprRhs(letOrFailExpr.Rhs), null, new List<AssignmentRhs>());
+        var assignOrReturn = new AssignOrReturnStmt(letOrFailExpr.Rhs.Origin, new List<Expression> { boundIdentifierExpr }, new ExprRhs(letOrFailExpr.Rhs), null, new List<AssignmentRhs>());
         varDecl = new VarDeclStmt(
           new RangeToken(letOrFailExpr.Lhs.Var.StartToken, letOrFailExpr.Rhs.EndToken),
-          new List<LocalVariable> { new(letOrFailExpr.Lhs.Var.RangeToken, letOrFailExpr.Lhs.Var.Name, new InferredTypeProxy(), false) }, assignOrReturn);
-        assignStatement = new AssignStatement(letOrFailExpr.Body.RangeToken, new List<Expression> { identifierExpr },
+          new List<LocalVariable> { new(letOrFailExpr.Lhs.Var.Origin, letOrFailExpr.Lhs.Var.Name, new InferredTypeProxy(), false) }, assignOrReturn);
+        assignStatement = new AssignStatement(letOrFailExpr.Body.Origin, new List<Expression> { identifierExpr },
           new List<AssignmentRhs> { new ExprRhs(letOrFailExpr.Body) });
-        newStmtStack.Last().Add(new BlockStmt(letOrFailExpr.RangeToken, new List<Statement> { varDecl, assignStatement }));
+        newStmtStack.Last().Add(new BlockStmt(letOrFailExpr.Origin, new List<Statement> { varDecl, assignStatement }));
         return identifierExpr;
       case LetOrFailExpr letOrFailExpr:
         newStmtStack.Last().Add(varDecl);
-        var assignOrReturnNoLhs = new AssignOrReturnStmt(letOrFailExpr.Rhs.RangeToken, new List<Expression>(), new ExprRhs(letOrFailExpr.Rhs), null, new List<AssignmentRhs>());
-        assignStatement = new AssignStatement(letOrFailExpr.Body.RangeToken, new List<Expression> { identifierExpr },
+        var assignOrReturnNoLhs = new AssignOrReturnStmt(letOrFailExpr.Rhs.Origin, new List<Expression>(), new ExprRhs(letOrFailExpr.Rhs), null, new List<AssignmentRhs>());
+        assignStatement = new AssignStatement(letOrFailExpr.Body.Origin, new List<Expression> { identifierExpr },
           new List<AssignmentRhs> { new ExprRhs(letOrFailExpr.Body) });
-        newStmtStack.Last().Add(new BlockStmt(letOrFailExpr.RangeToken, new List<Statement> { assignOrReturnNoLhs, assignStatement }));
+        newStmtStack.Last().Add(new BlockStmt(letOrFailExpr.Origin, new List<Statement> { assignOrReturnNoLhs, assignStatement }));
         return identifierExpr;
       case LetExpr letExpr:
         if (letExpr.Exact == false || letExpr.BoundVars.Count() != letExpr.RHSs.Count) {
@@ -405,19 +405,19 @@ public override Expression CloneExpr(Expression expr) {
         }
         newStmtStack.Last().Add(varDecl);
         i = 0;
-        var blockUpdate = new BlockStmt(letExpr.RangeToken, new List<Statement>());
+        var blockUpdate = new BlockStmt(letExpr.Origin, new List<Statement>());
         foreach (var boundVar in letExpr.BoundVars) {
           identifierExpr = new IdentifierExpr(letExpr.RHSs[i].StartToken, boundVar.Name);
-          assignStatement = new AssignStatement(letExpr.RHSs[i].RangeToken, new List<Expression> { identifierExpr },
+          assignStatement = new AssignStatement(letExpr.RHSs[i].Origin, new List<Expression> { identifierExpr },
               new List<AssignmentRhs> { new ExprRhs(letExpr.RHSs[i]) });
           varDecl = new VarDeclStmt(
             new RangeToken(boundVar.StartToken, letExpr.RHSs[i].EndToken),
-            new List<LocalVariable> { new(boundVar.RangeToken, boundVar.Name, new InferredTypeProxy(), false) }, assignStatement);
+            new List<LocalVariable> { new(boundVar.Origin, boundVar.Name, new InferredTypeProxy(), false) }, assignStatement);
           blockUpdate.Body.Add(varDecl);
           i += 1;
         }
         identifierExpr = new IdentifierExpr(letExpr.Body.StartToken, tmpVarName);
-        assignStatement = new AssignStatement(letExpr.Body.RangeToken, new List<Expression> { identifierExpr },
+        assignStatement = new AssignStatement(letExpr.Body.Origin, new List<Expression> { identifierExpr },
           new List<AssignmentRhs> { new ExprRhs(letExpr.Body) });
         blockUpdate.Body.Add(assignStatement);
         newStmtStack.Last().Add(blockUpdate);
@@ -426,7 +426,7 @@ public override Expression CloneExpr(Expression expr) {
         if (wasProcessingRhs) {
           break;
         }
-        assignStatement = new AssignStatement(applySuffix.RangeToken, new List<Expression> { identifierExpr },
+        assignStatement = new AssignStatement(applySuffix.Origin, new List<Expression> { identifierExpr },
           new List<AssignmentRhs> { new ExprRhs(applySuffix) });
         newStmtStack.Last().Add(varDecl);
         newStmtStack.Last().Add(assignStatement);
diff --git a/Source/DafnyTestGeneration/TestGenerator.cs b/Source/DafnyTestGeneration/TestGenerator.cs
index b33c1f167ca..12e3c9e9dec 100644
--- a/Source/DafnyTestGeneration/TestGenerator.cs
+++ b/Source/DafnyTestGeneration/TestGenerator.cs
@@ -90,7 +90,7 @@ public static async IAsyncEnumerable<string> GetDeadCodeStatistics(TextReader so
     private static void AddVerificationGoalsToEntryPoints(Program program) {
       foreach (var entryPoint in Utils.AllMemberDeclarationsWithAttribute(program.DefaultModule,
                  TestGenerationOptions.TestEntryAttribute)) {
-        var trivialAssertion = new AssertStmt(entryPoint.RangeToken,
+        var trivialAssertion = new AssertStmt(entryPoint.Origin,
           new LiteralExpr(entryPoint.StartToken, true), null, null);
         if (entryPoint is Method method && method.Body != null && method.Body.Body != null) {
           method.Body.Body.Insert(0, trivialAssertion);
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/at-attributes/at-attributes-typos.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/at-attributes/at-attributes-typos.dfy.expect
index 737e971d4ea..64e6e8c9292 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/at-attributes/at-attributes-typos.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/at-attributes/at-attributes-typos.dfy.expect
@@ -1,54 +1,54 @@
-at-attributes-typos.dfy(20,0): Error: @DisableNonlinearArithmetic attribute cannot be applied to function
-at-attributes-typos.dfy(19,0): Error: @NativeInt128 attribute cannot be applied to function
-at-attributes-typos.dfy(18,0): Error: @NativeUInt128 attribute cannot be applied to function
-at-attributes-typos.dfy(17,0): Error: @NativeInt64 attribute cannot be applied to function
-at-attributes-typos.dfy(16,0): Error: @NativeUInt64 attribute cannot be applied to function
-at-attributes-typos.dfy(15,0): Error: @NativeInt53 attribute cannot be applied to function
-at-attributes-typos.dfy(14,0): Error: @NativeInt32 attribute cannot be applied to function
-at-attributes-typos.dfy(13,0): Error: @NativeUInt32 attribute cannot be applied to function
-at-attributes-typos.dfy(12,0): Error: @NativeInt16 attribute cannot be applied to function
-at-attributes-typos.dfy(11,0): Error: @NativeUInt16 attribute cannot be applied to function
-at-attributes-typos.dfy(10,0): Error: @NativeInt8 attribute cannot be applied to function
-at-attributes-typos.dfy(9,0): Error: @NativeUInt8 attribute cannot be applied to function
-at-attributes-typos.dfy(8,0): Error: @NativeNone attribute cannot be applied to function
-at-attributes-typos.dfy(7,0): Error: @NativeInt attribute cannot be applied to function
-at-attributes-typos.dfy(6,0): Error: @NativeIntOrReal attribute cannot be applied to function
-at-attributes-typos.dfy(5,0): Error: @AutoContracts attribute cannot be applied to function
+at-attributes-typos.dfy(20,1): Error: @DisableNonlinearArithmetic attribute cannot be applied to function
+at-attributes-typos.dfy(19,1): Error: @NativeInt128 attribute cannot be applied to function
+at-attributes-typos.dfy(18,1): Error: @NativeUInt128 attribute cannot be applied to function
+at-attributes-typos.dfy(17,1): Error: @NativeInt64 attribute cannot be applied to function
+at-attributes-typos.dfy(16,1): Error: @NativeUInt64 attribute cannot be applied to function
+at-attributes-typos.dfy(15,1): Error: @NativeInt53 attribute cannot be applied to function
+at-attributes-typos.dfy(14,1): Error: @NativeInt32 attribute cannot be applied to function
+at-attributes-typos.dfy(13,1): Error: @NativeUInt32 attribute cannot be applied to function
+at-attributes-typos.dfy(12,1): Error: @NativeInt16 attribute cannot be applied to function
+at-attributes-typos.dfy(11,1): Error: @NativeUInt16 attribute cannot be applied to function
+at-attributes-typos.dfy(10,1): Error: @NativeInt8 attribute cannot be applied to function
+at-attributes-typos.dfy(9,1): Error: @NativeUInt8 attribute cannot be applied to function
+at-attributes-typos.dfy(8,1): Error: @NativeNone attribute cannot be applied to function
+at-attributes-typos.dfy(7,1): Error: @NativeInt attribute cannot be applied to function
+at-attributes-typos.dfy(6,1): Error: @NativeIntOrReal attribute cannot be applied to function
+at-attributes-typos.dfy(5,1): Error: @AutoContracts attribute cannot be applied to function
 at-attributes-typos.dfy(58,9): Error: the parameter named 'low' is already given positionally
-at-attributes-typos.dfy(56,9): Error: Argument to attribute Compile must be a literal
+at-attributes-typos.dfy(56,14): Error: Argument to attribute Compile must be a literal
 at-attributes-typos.dfy(55,20): Error: wrong number of arguments (got 2, but attribute 'Compile' expects at most 1: (0: bool))
 at-attributes-typos.dfy(54,15): Error: incorrect argument type for attribute parameter '0' (expected bool, found string)
-at-attributes-typos.dfy(82,0): Error: @Transparent attribute cannot be applied to method
+at-attributes-typos.dfy(82,1): Error: @Transparent attribute cannot be applied to method
 at-attributes-typos.dfy(80,31): Error: wrong number of arguments (got 1, but attribute 'IsolateAssertions' expects 0)
-at-attributes-typos.dfy(49,0): Error: @Synthesize attribute cannot be applied to module definition
-at-attributes-typos.dfy(48,0): Error: @IsolateAssertions attribute cannot be applied to module definition
-at-attributes-typos.dfy(47,0): Error: @VcsMaxSplits attribute cannot be applied to module definition
-at-attributes-typos.dfy(46,0): Error: @VcsMaxKeepGoingSplits attribute cannot be applied to module definition
-at-attributes-typos.dfy(45,0): Error: @VcsMaxCost attribute cannot be applied to module definition
-at-attributes-typos.dfy(44,0): Error: @TestEntry attribute cannot be applied to module definition
-at-attributes-typos.dfy(43,0): Error: @TestInline attribute cannot be applied to module definition
-at-attributes-typos.dfy(42,0): Error: @TestInline attribute cannot be applied to module definition
-at-attributes-typos.dfy(41,0): Error: @Test attribute cannot be applied to module definition
-at-attributes-typos.dfy(40,0): Error: @Verify attribute cannot be applied to module definition
-at-attributes-typos.dfy(39,0): Error: @TimeLimitMultiplier attribute cannot be applied to module definition
-at-attributes-typos.dfy(38,0): Error: @TimeLimit attribute cannot be applied to module definition
-at-attributes-typos.dfy(37,0): Error: @ResourceLimit attribute cannot be applied to module definition
+at-attributes-typos.dfy(49,1): Error: @Synthesize attribute cannot be applied to module definition
+at-attributes-typos.dfy(48,1): Error: @IsolateAssertions attribute cannot be applied to module definition
+at-attributes-typos.dfy(47,16): Error: @VcsMaxSplits attribute cannot be applied to module definition
+at-attributes-typos.dfy(46,25): Error: @VcsMaxKeepGoingSplits attribute cannot be applied to module definition
+at-attributes-typos.dfy(45,14): Error: @VcsMaxCost attribute cannot be applied to module definition
+at-attributes-typos.dfy(44,1): Error: @TestEntry attribute cannot be applied to module definition
+at-attributes-typos.dfy(43,14): Error: @TestInline attribute cannot be applied to module definition
+at-attributes-typos.dfy(42,1): Error: @TestInline attribute cannot be applied to module definition
+at-attributes-typos.dfy(41,1): Error: @Test attribute cannot be applied to module definition
+at-attributes-typos.dfy(40,1): Error: @Verify attribute cannot be applied to module definition
+at-attributes-typos.dfy(39,22): Error: @TimeLimitMultiplier attribute cannot be applied to module definition
+at-attributes-typos.dfy(38,15): Error: @TimeLimit attribute cannot be applied to module definition
+at-attributes-typos.dfy(37,19): Error: @ResourceLimit attribute cannot be applied to module definition
 at-attributes-typos.dfy(37,19): Error: incorrect argument type for attribute parameter '0' (expected seq<char>, found int)
-at-attributes-typos.dfy(36,0): Error: @Priority attribute cannot be applied to module definition
-at-attributes-typos.dfy(35,0): Error: @Print attribute cannot be applied to module definition
-at-attributes-typos.dfy(34,0): Error: @VerifyOnly attribute cannot be applied to module definition
-at-attributes-typos.dfy(33,0): Error: @TailRecursion attribute cannot be applied to module definition
-at-attributes-typos.dfy(32,0): Error: @Concurrent attribute cannot be applied to module definition
-at-attributes-typos.dfy(31,0): Error: @Axiom attribute cannot be applied to module definition
-at-attributes-typos.dfy(30,0): Error: @AutoRevealDependencies attribute cannot be applied to module definition
-at-attributes-typos.dfy(29,0): Error: @AutoRevealDependenciesAll attribute cannot be applied to module definition
-at-attributes-typos.dfy(28,0): Error: @AutoRevealDependenciesAll attribute cannot be applied to module definition
-at-attributes-typos.dfy(27,0): Error: @AutoRequires attribute cannot be applied to module definition
-at-attributes-typos.dfy(64,0): Error: @Fuel attribute cannot be applied to datatype
-at-attributes-typos.dfy(67,0): Error: @Fuel attribute cannot be applied to codatatype
-at-attributes-typos.dfy(70,0): Error: @Fuel attribute cannot be applied to type synonym
-at-attributes-typos.dfy(73,0): Error: @Fuel attribute cannot be applied to subset type
-at-attributes-typos.dfy(76,0): Error: @Fuel attribute cannot be applied to newtype
+at-attributes-typos.dfy(36,11): Error: @Priority attribute cannot be applied to module definition
+at-attributes-typos.dfy(35,1): Error: @Print attribute cannot be applied to module definition
+at-attributes-typos.dfy(34,1): Error: @VerifyOnly attribute cannot be applied to module definition
+at-attributes-typos.dfy(33,1): Error: @TailRecursion attribute cannot be applied to module definition
+at-attributes-typos.dfy(32,1): Error: @Concurrent attribute cannot be applied to module definition
+at-attributes-typos.dfy(31,1): Error: @Axiom attribute cannot be applied to module definition
+at-attributes-typos.dfy(30,35): Error: @AutoRevealDependencies attribute cannot be applied to module definition
+at-attributes-typos.dfy(29,31): Error: @AutoRevealDependenciesAll attribute cannot be applied to module definition
+at-attributes-typos.dfy(28,32): Error: @AutoRevealDependenciesAll attribute cannot be applied to module definition
+at-attributes-typos.dfy(27,1): Error: @AutoRequires attribute cannot be applied to module definition
+at-attributes-typos.dfy(64,10): Error: @Fuel attribute cannot be applied to datatype
+at-attributes-typos.dfy(67,10): Error: @Fuel attribute cannot be applied to codatatype
+at-attributes-typos.dfy(70,10): Error: @Fuel attribute cannot be applied to type synonym
+at-attributes-typos.dfy(73,10): Error: @Fuel attribute cannot be applied to subset type
+at-attributes-typos.dfy(76,10): Error: @Fuel attribute cannot be applied to newtype
 at-attributes-typos.dfy(57,1): Error: unresolved identifier: fuel
 at-attributes-typos.dfy(53,1): Error: unresolved identifier: compile
 at-attributes-typos.dfy(79,1): Error: unresolved identifier: isolate_assertions
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/auditor/TestAuditor.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/auditor/TestAuditor.dfy.expect
index ff81640d3a4..7a50ef57fea 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/auditor/TestAuditor.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/auditor/TestAuditor.dfy.expect
@@ -1,8 +1,8 @@
-TestAuditor.dfy(24,25): Warning: This ensures clause is part of a bodyless method. Add the {:axiom} attribute to it or the enclosing method to suppress this warning
+TestAuditor.dfy(24,10): Warning: This ensures clause is part of a bodyless method. Add the {:axiom} attribute to it or the enclosing method to suppress this warning
 TestAuditor.dfy(38,2): Warning: assume statement has no {:axiom} annotation
 TestAuditor.dfy(136,2): Warning: assume statement has no {:axiom} annotation
-TestAuditor.dfy(150,9): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
-TestAuditor.dfy(154,7): Warning: Members with {:only} temporarily disable the verification of other members in the entire file
+TestAuditor.dfy(150,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+TestAuditor.dfy(154,9): Warning: Members with {:only} temporarily disable the verification of other members in the entire file
 TestAuditor.dfy(95,4): Warning: this forall statement has no body
 TestAuditor.dfy(102,4): Warning: this loop has no body (loop frame: i)
 TestAuditor.dfy(139,2): Warning: this forall statement has no body
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/cloudmake/CloudMake-ParallelBuilds.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/cloudmake/CloudMake-ParallelBuilds.dfy.expect
index b8e3c6a9885..942402b5d01 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/cloudmake/CloudMake-ParallelBuilds.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/cloudmake/CloudMake-ParallelBuilds.dfy.expect
@@ -1,2 +1,2 @@
 
-Dafny program verifier finished with 66 verified, 0 errors
+Dafny program verifier finished with 65 verified, 0 errors
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/comp/rust/bymethod.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/comp/rust/bymethod.dfy.expect
index 585ba6c28b2..7420ef1bf1d 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/comp/rust/bymethod.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/comp/rust/bymethod.dfy.expect
@@ -1,3 +1,3 @@
 
-Dafny program verifier finished with 8 verified, 0 errors
+Dafny program verifier finished with 6 verified, 0 errors
 Everything ok
\ No newline at end of file
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/AssumptionVariables0.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/AssumptionVariables0.dfy.expect
index e659c37c127..d35bd59bb05 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/AssumptionVariables0.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/AssumptionVariables0.dfy.expect
@@ -1,5 +1,5 @@
 AssumptionVariables0.dfy(7,31): Error: there may be at most one assignment to an assumption variable, the RHS of which must match the expression "a0 && <boolean expression>"
-AssumptionVariables0.dfy(8,44): Error: there may be at most one assignment to an assumption variable, the RHS of which must match the expression "a2 && <boolean expression>"
+AssumptionVariables0.dfy(8,35): Error: there may be at most one assignment to an assumption variable, the RHS of which must match the expression "a2 && <boolean expression>"
 AssumptionVariables0.dfy(16,7): Error: there may be at most one assignment to an assumption variable, the RHS of which must match the expression "a3 && <boolean expression>"
 AssumptionVariables0.dfy(18,7): Error: there may be at most one assignment to an assumption variable, the RHS of which must match the expression "a3 && <boolean expression>"
 AssumptionVariables0.dfy(28,7): Error: there may be at most one assignment to an assumption variable, the RHS of which must match the expression "a0 && <boolean expression>"
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/AutoContracts.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/AutoContracts.dfy.expect
index d046a3ece47..be190dd0376 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/AutoContracts.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/AutoContracts.dfy.expect
@@ -573,24 +573,18 @@ module N2 refines N1 {
   */
 }
 AutoContracts.dfy(17,4): Error: a postcondition could not be proved on this return path
-AutoContracts.dfy(12,20): Related location: this proposition could not be proved
+AutoContracts.dfy(12,20): Related location: Could not prove: Valid
 AutoContracts.dfy(17,4): Error: a postcondition could not be proved on this return path
-AutoContracts.dfy(12,20): Related location: this proposition could not be proved
+AutoContracts.dfy(12,20): Related location: Could not prove: Valid
 AutoContracts.dfy(17,4): Error: a postcondition could not be proved on this return path
-AutoContracts.dfy(12,20): Related location: this proposition could not be proved
+AutoContracts.dfy(12,20): Related location: Could not prove: Valid
 AutoContracts.dfy(17,4): Error: a postcondition could not be proved on this return path
 AutoContracts.dfy(17,4): Error: a postcondition could not be proved on this return path
-AutoContracts.dfy(12,20): Related location: this proposition could not be proved
-AutoContracts.dfy(5,25): Related location: this proposition could not be proved
+AutoContracts.dfy(12,20): Related location: Could not prove: Valid
+AutoContracts.dfy(5,25): Related location: Could not prove: D
 AutoContracts.dfy(50,4): Error: a postcondition could not be proved on this return path
 AutoContracts.dfy(49,24): Related location: this is the postcondition that could not be proved
 AutoContracts.dfy(79,21): Error: a postcondition could not be proved on this return path
-AutoContracts.dfy(60,16): Related location: this is the postcondition that could not be proved
-AutoContracts.dfy(79,21): Error: a postcondition could not be proved on this return path
-AutoContracts.dfy(60,16): Related location: this is the postcondition that could not be proved
-AutoContracts.dfy[N1](65,20): Related location: this proposition could not be proved
-AutoContracts.dfy(79,21): Error: a postcondition could not be proved on this return path
-AutoContracts.dfy(60,16): Related location: this is the postcondition that could not be proved
-AutoContracts.dfy[N1](65,20): Related location: this proposition could not be proved
+AutoContracts.dfy(60,16): Related location: this postcondition might not hold: Y
 
-Dafny program verifier finished with 36 verified, 9 errors
+Dafny program verifier finished with 36 verified, 7 errors
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/ChainingDisjointTests.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/ChainingDisjointTests.dfy.expect
index ee9cf967055..83681c64da1 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/ChainingDisjointTests.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/ChainingDisjointTests.dfy.expect
@@ -1,6 +1,6 @@
 ChainingDisjointTests.dfy(49,2): Error: a postcondition could not be proved on this return path
 ChainingDisjointTests.dfy(48,14): Related location: this is the postcondition that could not be proved
-ChainingDisjointTests.dfy(42,22): Related location: this proposition could not be proved
+ChainingDisjointTests.dfy(42,22): Related location: Could not prove: SCons
 ChainingDisjointTests.dfy(58,13): Error: assertion might not hold
 ChainingDisjointTests.dfy(58,18): Error: assertion might not hold
 ChainingDisjointTests.dfy(58,23): Error: assertion might not hold
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/CoPrefix.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/CoPrefix.dfy.expect
index d5f27399a5a..37e77e505e7 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/CoPrefix.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/CoPrefix.dfy.expect
@@ -4,7 +4,7 @@ CoPrefix.dfy(114,0): Error: a postcondition could not be proved on this return p
 CoPrefix.dfy(113,10): Related location: this is the postcondition that could not be proved
 CoPrefix.dfy(101,16): Related location: this proposition could not be proved
 CoPrefix.dfy(142,24): Error: assertion might not hold
-CoPrefix.dfy(117,22): Related location: this proposition could not be proved
+CoPrefix.dfy(117,22): Related location: Could not prove: TCons
 CoPrefix.dfy(151,0): Error: a postcondition could not be proved on this return path
 CoPrefix.dfy(150,10): Related location: this is the postcondition that could not be proved
 CoPrefix.dfy(164,2): Error: a postcondition could not be proved on this return path
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/CoinductiveProofs.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/CoinductiveProofs.dfy.expect
index 1c87811a450..0932dfebc5b 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/CoinductiveProofs.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/CoinductiveProofs.dfy.expect
@@ -25,10 +25,10 @@ CoinductiveProofs.dfy(163,10): Related location: this is the postcondition that
 CoinductiveProofs.dfy(159,2): Related location: this proposition could not be proved
 CoinductiveProofs.dfy(203,0): Error: a postcondition could not be proved on this return path
 CoinductiveProofs.dfy(202,21): Related location: this is the postcondition that could not be proved
-CoinductiveProofs.dfy(4,23): Related location: this proposition could not be proved
+CoinductiveProofs.dfy(4,23): Related location: Could not prove: Cons
 CoinductiveProofs.dfy(209,0): Error: a postcondition could not be proved on this return path
 CoinductiveProofs.dfy(208,21): Related location: this is the postcondition that could not be proved
-CoinductiveProofs.dfy(4,23): Related location: this proposition could not be proved
+CoinductiveProofs.dfy(4,23): Related location: Could not prove: Cons
 
 Dafny program verifier finished with 23 verified, 12 errors
 Total resources used is 777634
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/DTypes.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/DTypes.dfy.expect
index 2d1000e136e..dadc9178aaa 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/DTypes.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/DTypes.dfy.expect
@@ -9,12 +9,12 @@ DTypes.dfy(64,13): Warning: the type of the other operand is a non-null type, so
 DTypes.dfy(18,13): Error: assertion might not hold
 DTypes.dfy(56,17): Error: assertion might not hold
 DTypes.dfy(121,11): Error: assertion might not hold
-DTypes.dfy(93,29): Related location: this proposition could not be proved
+DTypes.dfy(93,29): Related location: Could not prove: Branch
 DTypes.dfy(127,11): Error: assertion might not hold
-DTypes.dfy(93,19): Related location: this proposition could not be proved
+DTypes.dfy(93,19): Related location: Could not prove: Leaf
 DTypes.dfy(137,11): Error: assertion might not hold
 DTypes.dfy(132,4): Related location: this proposition could not be proved
-DTypes.dfy(93,19): Related location: this proposition could not be proved
+DTypes.dfy(93,19): Related location: Could not prove: Leaf
 DTypes.dfy(156,11): Error: assertion might not hold
 DTypes.dfy(179,2): Error: a postcondition could not be proved on this return path
 DTypes.dfy(178,14): Related location: this is the postcondition that could not be proved
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/DecreasesTo3.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/DecreasesTo3.dfy.expect
index 105a92716d3..a5d651f5798 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/DecreasesTo3.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/DecreasesTo3.dfy.expect
@@ -1,4 +1,4 @@
-DecreasesTo3.dfy(5,31): Error: assertion might not hold
+DecreasesTo3.dfy(5,34): Error: assertion might not hold
  Asserted expression: (1 decreases to 0) && (0 decreases to 1)
 DecreasesTo3.dfy(9,11): Error: assertion might not hold
  Asserted expression: 0 decreases to 1
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/DefaultParameters.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/DefaultParameters.dfy.expect
index b7e9566eb69..2dcb55c9240 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/DefaultParameters.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/DefaultParameters.dfy.expect
@@ -75,6 +75,6 @@ DefaultParameters.dfy(521,40): Error: insufficient reads clause to read field; M
 DefaultParameters.dfy(524,49): Error: insufficient reads clause to read field; Mutable fields cannot be accessed within certain scopes, such as default values, the right-hand side of constants, or co-recursive calls
 DefaultParameters.dfy(548,38): Error: insufficient reads clause to read field; Mutable fields cannot be accessed within certain scopes, such as default values, the right-hand side of constants, or co-recursive calls
 DefaultParameters.dfy(601,11): Error: assertion might not hold
-DefaultParameters.dfy(582,18): Related location: this proposition could not be proved
+DefaultParameters.dfy(582,18): Related location: Could not prove: Q
 
 Dafny program verifier finished with 72 verified, 74 errors
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/ExtremeReads.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/ExtremeReads.dfy.expect
index 587974ee82f..26fc1cd74cf 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/ExtremeReads.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/ExtremeReads.dfy.expect
@@ -9,27 +9,27 @@ ExtremeReads.dfy(26,2): Related location: this proposition could not be proved
 ExtremeReads.dfy(105,11): Error: assertion might not hold
 ExtremeReads.dfy(89,2): Related location: this proposition could not be proved
 ExtremeReads.dfy(127,11): Error: assertion might not hold
-ExtremeReads.dfy(9,19): Related location: this proposition could not be proved
+ExtremeReads.dfy(9,19): Related location: Could not prove: P
 ExtremeReads.dfy(127,11): Error: assertion might not hold
 ExtremeReads.dfy(13,20): Related location: this proposition could not be proved
 ExtremeReads.dfy(130,11): Error: assertion might not hold
-ExtremeReads.dfy(9,19): Related location: this proposition could not be proved
+ExtremeReads.dfy(9,19): Related location: Could not prove: P
 ExtremeReads.dfy(130,11): Error: assertion might not hold
 ExtremeReads.dfy(13,20): Related location: this proposition could not be proved
 ExtremeReads.dfy(149,11): Error: assertion might not hold
-ExtremeReads.dfy(16,19): Related location: this proposition could not be proved
+ExtremeReads.dfy(16,19): Related location: Could not prove: Q
 ExtremeReads.dfy(149,11): Error: assertion might not hold
 ExtremeReads.dfy(20,20): Related location: this proposition could not be proved
 ExtremeReads.dfy(168,11): Error: assertion might not hold
-ExtremeReads.dfy(23,19): Related location: this proposition could not be proved
+ExtremeReads.dfy(23,19): Related location: Could not prove: R
 ExtremeReads.dfy(168,11): Error: assertion might not hold
 ExtremeReads.dfy(26,2): Related location: this proposition could not be proved
 ExtremeReads.dfy(171,11): Error: assertion might not hold
-ExtremeReads.dfy(23,19): Related location: this proposition could not be proved
+ExtremeReads.dfy(23,19): Related location: Could not prove: R
 ExtremeReads.dfy(171,11): Error: assertion might not hold
 ExtremeReads.dfy(26,2): Related location: this proposition could not be proved
 ExtremeReads.dfy(181,11): Error: assertion might not hold
-ExtremeReads.dfy(86,16): Related location: this proposition could not be proved
+ExtremeReads.dfy(86,16): Related location: Could not prove: V
 ExtremeReads.dfy(181,11): Error: assertion might not hold
 ExtremeReads.dfy(89,2): Related location: this proposition could not be proved
 
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/MapMergeSubtraction.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/MapMergeSubtraction.dfy.expect
index 00f85e08cc1..4de2d1f6f3b 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/MapMergeSubtraction.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/MapMergeSubtraction.dfy.expect
@@ -6,5 +6,5 @@ MapMergeSubtraction.dfy(49,19): Error: type of right argument to + (map<bool, re
 MapMergeSubtraction.dfy(51,15): Error: map subtraction expects right-hand operand to have type set<bool> (instead got set<int>) (covariant type parameter would require int <: bool)
 MapMergeSubtraction.dfy(65,15): Error: map subtraction expects right-hand operand to have type set<int> (instead got iset<int>)
 MapMergeSubtraction.dfy(67,15): Error: map subtraction expects right-hand operand to have type set<int> (instead got iset<int>)
-MapMergeSubtraction.dfy(84,13): Error: RHS (of type set<int>) not assignable to LHS (of type map<int, real>)
+MapMergeSubtraction.dfy(84,7): Error: RHS (of type set<int>) not assignable to LHS (of type map<int, real>)
 9 resolution/type errors detected in MapMergeSubtraction.dfy
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/ModuleExport.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/ModuleExport.dfy.expect
index 1e577230612..0a8538eb7a3 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/ModuleExport.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/ModuleExport.dfy.expect
@@ -9,7 +9,7 @@ ModuleExport.dfy(66,2): Warning: this branch is redundant
 ModuleExport.dfy(73,19): Error: Public2 must be an export of F to be extended
 ModuleExport.dfy(74,34): Error: 'g2' must be a member of 'F' to be exported
 ModuleExport.dfy(100,9): Error: no default export set declared in module: G
-ModuleExport.dfy(125,17): Error: member 'Init' has not been imported in this scope and cannot be accessed here
+ModuleExport.dfy(125,19): Error: member 'Init' has not been imported in this scope and cannot be accessed here
 ModuleExport.dfy(136,8): Error: when allocating an object of type 'C', one of its constructor methods must be called
 ModuleExport.dfy(137,12): Error: when allocating an object of imported type 'D', one of its constructor methods must be called
 ModuleExport.dfy(234,11): Error: Type or type parameter is not declared in this scope: X (did you forget to qualify a name or declare a module import 'opened'?) (note that names in outer modules are not visible in contained modules)
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/Modules0.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/Modules0.dfy.expect
index 6011e6957e2..805d2997ad6 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/Modules0.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/Modules0.dfy.expect
@@ -38,7 +38,7 @@ Modules0.dfy(319,11): Error: Type or type parameter is not declared in this scop
 Modules0.dfy(320,11): Error: Type or type parameter is not declared in this scope: Wazzup (did you forget to qualify a name or declare a module import 'opened'?) (note that names in outer modules are not visible in contained modules)
 Modules0.dfy(321,17): Error: module 'Q_Imp' does not declare a type 'Edon'
 Modules0.dfy(323,13): Error: new can be applied only to class types (got Q_Imp.List<?>)
-Modules0.dfy(324,23): Error: member 'Create' does not exist in class 'Klassy'
+Modules0.dfy(324,30): Error: member 'Create' does not exist in class 'Klassy'
 Modules0.dfy(318,13): Error: arguments must have comparable types (got Q_Imp.Node and Node)
 Modules0.dfy(349,11): Error: a datatype declaration (T) in a refinement module can only refine a datatype declaration or replace an abstract type declaration
 34 resolution/type errors detected in Modules0.dfy
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/Modules1.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/Modules1.dfy.expect
index 4e2407359d0..d413a5aba4d 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/Modules1.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/Modules1.dfy.expect
@@ -1,6 +1,6 @@
 Modules1.dfy(131,14): Warning: This ensures clause is part of a bodyless method. Add the {:axiom} attribute to it or the enclosing method to suppress this warning
 Modules1.dfy(56,8): Error: decreases expression must be bounded below by 0
-Modules1.dfy(54,12): Related location: this proposition could not be proved
+Modules1.dfy(54,12): Related location: Could not prove: x
 Modules1.dfy(62,8): Error: decreases clause might not decrease
 Modules1.dfy(82,15): Error: assertion might not hold
 Modules1.dfy(95,15): Error: assertion might not hold
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/RealCompare.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/RealCompare.dfy.expect
index bcb5d05c33d..8fbb41e54c7 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/RealCompare.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/RealCompare.dfy.expect
@@ -1,6 +1,6 @@
 RealCompare.dfy(35,5): Error: decreases clause might not decrease
 RealCompare.dfy(50,3): Error: decreases expression must be bounded below by 0.0
-RealCompare.dfy(48,12): Related location: this proposition could not be proved
+RealCompare.dfy(48,12): Related location: Could not prove: x
 RealCompare.dfy(141,11): Error: assertion might not hold
 RealCompare.dfy(156,11): Error: assertion might not hold
 
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/Refinement.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/Refinement.dfy.expect
index eba5fb51b86..9d0c3557460 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/Refinement.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/Refinement.dfy.expect
@@ -18,7 +18,7 @@ Refinement.dfy(276,7): Warning: the ... refinement feature in statements is depr
 Refinement.dfy(233,4): Warning: this loop has no body (loop frame: i)
 Refinement.dfy(15,4): Error: a postcondition could not be proved on this return path
 Refinement.dfy(14,16): Related location: this is the postcondition that could not be proved
-Refinement.dfy[B](15,4): Error: a postcondition could not be proved on this return path
+Refinement.dfy(15,4): Error: a postcondition could not be proved on this return path
 Refinement.dfy(33,19): Related location: this is the postcondition that could not be proved
 Refinement.dfy(69,15): Error: assertion might not hold
 Refinement.dfy(80,16): Error: assertion might not hold
@@ -27,9 +27,9 @@ Refinement.dfy(78,14): Related location: this is the postcondition that could no
 Refinement.dfy(102,2): Error: a postcondition could not be proved on this return path
 Refinement.dfy(83,14): Related location: this is the postcondition that could not be proved
 Refinement.dfy(198,6): Error: assertion might not hold
-Refinement.dfy[IncorrectConcrete](122,18): Related location: this proposition could not be proved
+Refinement.dfy[IncorrectConcrete](122,18): Related location: Could not prove: Valid()
 Refinement.dfy(204,6): Error: assertion might not hold
-Refinement.dfy[IncorrectConcrete](131,18): Related location: this proposition could not be proved
+Refinement.dfy[IncorrectConcrete](131,18): Related location: Could not prove: Valid()
 Refinement.dfy(209,6): Error: assertion might not hold
 Refinement.dfy[IncorrectConcrete](137,23): Related location: this proposition could not be proved
 Refinement.dfy(253,6): Error: a postcondition could not be proved on this return path
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/TypeConstraints.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/TypeConstraints.dfy.expect
index 040e618a2cd..623be4b7b2e 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/TypeConstraints.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/TypeConstraints.dfy.expect
@@ -1,6 +1,6 @@
 TypeConstraints.dfy(42,6): Error: RHS (of type int) not assignable to LHS (of type bool)
 TypeConstraints.dfy(49,6): Error: RHS (of type int) not assignable to LHS (of type bool)
-TypeConstraints.dfy(56,15): Error: RHS (of type int) not assignable to LHS (of type bool)
+TypeConstraints.dfy(56,9): Error: RHS (of type int) not assignable to LHS (of type bool)
 TypeConstraints.dfy(65,6): Error: RHS (of type bool) not assignable to LHS (of type int)
 TypeConstraints.dfy(80,6): Error: RHS (of type MyInt) not assignable to LHS (of type int)
 TypeConstraints.dfy(81,6): Error: RHS (of type int) not assignable to LHS (of type MyInt)
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/TypeConstraintsRefresh.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/TypeConstraintsRefresh.dfy.expect
index b0d2c9614d7..475a725c910 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/TypeConstraintsRefresh.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny0/TypeConstraintsRefresh.dfy.expect
@@ -1,6 +1,6 @@
-TypeConstraintsRefresh.dfy(40,15): Error: RHS (of type bool) not assignable to LHS (of type int)
-TypeConstraintsRefresh.dfy(48,15): Error: RHS (of type bool) not assignable to LHS (of type int)
-TypeConstraintsRefresh.dfy(56,15): Error: RHS (of type int) not assignable to LHS (of type bool)
+TypeConstraintsRefresh.dfy(40,9): Error: RHS (of type bool) not assignable to LHS (of type int)
+TypeConstraintsRefresh.dfy(48,9): Error: RHS (of type bool) not assignable to LHS (of type int)
+TypeConstraintsRefresh.dfy(56,9): Error: RHS (of type int) not assignable to LHS (of type bool)
 TypeConstraintsRefresh.dfy(65,6): Error: RHS (of type bool) not assignable to LHS (of type int)
 TypeConstraintsRefresh.dfy(80,6): Error: RHS (of type MyInt) not assignable to LHS (of type int)
 TypeConstraintsRefresh.dfy(81,6): Error: RHS (of type int) not assignable to LHS (of type MyInt)
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny3/Inc.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny3/Inc.dfy.expect
index cca28a8d4cc..d67773bcea4 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny3/Inc.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny3/Inc.dfy.expect
@@ -20,6 +20,6 @@ Inc.dfy(247,2): Error: a postcondition could not be proved on this return path
 Inc.dfy(244,12): Related location: this is the postcondition that could not be proved
 Inc.dfy(318,17): Error: cannot prove termination; try supplying a decreases clause
 Inc.dfy(318,17): Error: decreases expression at index 1 must be bounded below by 0
-Inc.dfy(303,26): Related location: this proposition could not be proved
+Inc.dfy(303,26): Related location: Could not prove: s
 
 Dafny program verifier finished with 8 verified, 12 errors
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny4/ExpandedGuardednessNeg.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny4/ExpandedGuardednessNeg.dfy.expect
index 74351cc3738..8d80e178d66 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny4/ExpandedGuardednessNeg.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/dafny4/ExpandedGuardednessNeg.dfy.expect
@@ -1,8 +1,8 @@
 ExpandedGuardednessNeg.dfy(8,17): Error: cannot prove termination; try supplying a decreases clause (note that calls cannot be co-recursive in this context)
 ExpandedGuardednessNeg.dfy(8,17): Error: decreases expression must be bounded below by 0
-ExpandedGuardednessNeg.dfy(6,20): Related location: this proposition could not be proved
+ExpandedGuardednessNeg.dfy(6,20): Related location: Could not prove: n
 ExpandedGuardednessNeg.dfy(13,16): Error: cannot prove termination; try supplying a decreases clause
 ExpandedGuardednessNeg.dfy(13,16): Error: decreases expression must be bounded below by 0
-ExpandedGuardednessNeg.dfy(11,27): Related location: this proposition could not be proved
+ExpandedGuardednessNeg.dfy(11,27): Related location: Could not prove: n
 
 Dafny program verifier finished with 0 verified, 4 errors
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/examples/induction-principle-code/EliminateMulZero.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/examples/induction-principle-code/EliminateMulZero.dfy.expect
index 9e74af046b4..8a923ac640e 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/examples/induction-principle-code/EliminateMulZero.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/examples/induction-principle-code/EliminateMulZero.dfy.expect
@@ -1,2 +1,2 @@
 
-Dafny program verifier finished with 29 verified, 0 errors
+Dafny program verifier finished with 28 verified, 0 errors
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/examples/induction-principle-code/Equiv.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/examples/induction-principle-code/Equiv.dfy.expect
index 94ea176b77c..9e74af046b4 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/examples/induction-principle-code/Equiv.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/examples/induction-principle-code/Equiv.dfy.expect
@@ -1,2 +1,2 @@
 
-Dafny program verifier finished with 30 verified, 0 errors
+Dafny program verifier finished with 29 verified, 0 errors
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/examples/induction-principle-code/Pure.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/examples/induction-principle-code/Pure.dfy.expect
index be068182e1e..25822a5c6cc 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/examples/induction-principle-code/Pure.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/examples/induction-principle-code/Pure.dfy.expect
@@ -1,2 +1,2 @@
 
-Dafny program verifier finished with 25 verified, 0 errors
+Dafny program verifier finished with 24 verified, 0 errors
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/examples/induction-principle-code/VarUnchanged.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/examples/induction-principle-code/VarUnchanged.dfy.expect
index 8a923ac640e..e4a6850707d 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/examples/induction-principle-code/VarUnchanged.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/examples/induction-principle-code/VarUnchanged.dfy.expect
@@ -1,2 +1,2 @@
 
-Dafny program verifier finished with 28 verified, 0 errors
+Dafny program verifier finished with 27 verified, 0 errors
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-3095.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-3095.dfy.expect
index c47296d065f..61174aa333a 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-3095.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-3095.dfy.expect
@@ -1,23 +1,23 @@
-git-issue-3095.dfy(18,9): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
-git-issue-3095.dfy(19,9): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
-git-issue-3095.dfy(25,9): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-3095.dfy(18,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-3095.dfy(19,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-3095.dfy(25,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
 git-issue-3095.dfy(25,16): Warning: {:only} only accepts "before" or "after" as an optional argument
-git-issue-3095.dfy(26,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
-git-issue-3095.dfy(32,9): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
-git-issue-3095.dfy(40,9): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
-git-issue-3095.dfy(49,9): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
-git-issue-3095.dfy(51,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
-git-issue-3095.dfy(62,9): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
-git-issue-3095.dfy(71,9): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
-git-issue-3095.dfy(73,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
-git-issue-3095.dfy(83,9): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
-git-issue-3095.dfy(85,9): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
-git-issue-3095.dfy(93,9): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
-git-issue-3095.dfy(95,9): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
-git-issue-3095.dfy(103,9): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
-git-issue-3095.dfy(105,9): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
-git-issue-3095.dfy(114,9): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
-git-issue-3095.dfy(116,9): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-3095.dfy(26,13): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-3095.dfy(32,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-3095.dfy(40,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-3095.dfy(49,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-3095.dfy(51,13): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-3095.dfy(62,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-3095.dfy(71,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-3095.dfy(73,13): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-3095.dfy(83,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-3095.dfy(85,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-3095.dfy(93,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-3095.dfy(95,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-3095.dfy(103,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-3095.dfy(105,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-3095.dfy(114,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-3095.dfy(116,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
 git-issue-3095.dfy(19,19): Error: assertion might not hold
 git-issue-3095.dfy(26,21): Error: assertion might not hold
 git-issue-3095.dfy(27,15): Error: assertion might not hold
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-4055.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-4055.dfy.expect
index 824afee9684..13fd2a3242b 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-4055.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-4055.dfy.expect
@@ -1,4 +1,4 @@
-git-issue-4055.dfy(12,9): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+git-issue-4055.dfy(12,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
 git-issue-4055.dfy(7,9): Error: assertion might not hold
 git-issue-4055.dfy(18,9): Error: assertion might not hold
 
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-4074.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-4074.dfy.expect
index 129599a02ad..cdf65fe3ff5 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-4074.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-4074.dfy.expect
@@ -1,7 +1,7 @@
-git-issue-4074.dfy(23,9): Warning: Members with {:only} temporarily disable the verification of other members in the entire file
-git-issue-4074.dfy(4,7): Warning: Members with {:only} temporarily disable the verification of other members in the entire file
+git-issue-4074.dfy(23,11): Warning: Members with {:only} temporarily disable the verification of other members in the entire file
+git-issue-4074.dfy(4,9): Warning: Members with {:only} temporarily disable the verification of other members in the entire file
 git-issue-4074.dfy(4,14): Warning: {:only} on members does not support arguments
-git-issue-4074.dfy(13,9): Warning: Members with {:only} temporarily disable the verification of other members in the entire file
+git-issue-4074.dfy(13,11): Warning: Members with {:only} temporarily disable the verification of other members in the entire file
 git-issue-4074.dfy(5,9): Error: assertion might not hold
 git-issue-4074.dfy(14,11): Error: assertion might not hold
 git-issue-4074.dfy(24,11): Error: assertion might not hold
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-4939a.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-4939a.dfy.expect
index 5ec3e0aa53f..74f50865943 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-4939a.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-4939a.dfy.expect
@@ -1,13 +1,13 @@
-git-issue-4939a.dfy(99,19): Warning: This ensures clause is part of a bodyless function. Add the {:axiom} attribute to it or the enclosing function to suppress this warning
+git-issue-4939a.dfy(99,15): Warning: This ensures clause is part of a bodyless function. Add the {:axiom} attribute to it or the enclosing function to suppress this warning
 git-issue-4939a.dfy(142,11): Warning: because of cyclic dependencies among constructor argument types, no instances of datatype 'T' can be constructed
 git-issue-4939a.dfy(144,11): Warning: because of cyclic dependencies among constructor argument types, no instances of datatype 'Mutual' can be constructed
 git-issue-4939a.dfy(145,11): Warning: because of cyclic dependencies among constructor argument types, no instances of datatype 'Nutual' can be constructed
 git-issue-4939a.dfy(25,32): Error: cannot prove termination; try supplying a decreases clause
 git-issue-4939a.dfy(68,12): Error: cannot prove termination; try supplying a decreases clause
 git-issue-4939a.dfy(68,12): Error: decreases expression must be bounded below by 0
-git-issue-4939a.dfy(67,23): Related location: this proposition could not be proved
+git-issue-4939a.dfy(67,23): Related location: Could not prove: i
 git-issue-4939a.dfy(105,27): Error: cannot prove termination; try supplying a decreases clause
 git-issue-4939a.dfy(105,27): Error: decreases expression must be bounded below by 0
-git-issue-4939a.dfy(104,23): Related location: this proposition could not be proved
+git-issue-4939a.dfy(104,23): Related location: Could not prove: i
 
 Dafny program verifier finished with 12 verified, 5 errors
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-5730/git-issue-5730.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-5730/git-issue-5730.dfy.expect
index 2d548e6365e..b0067456b19 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-5730/git-issue-5730.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-5730/git-issue-5730.dfy.expect
@@ -1,4 +1,4 @@
-git-issue-5730.dfy(5,9): Warning: Members with {:only} temporarily disable the verification of other members in the entire file
+git-issue-5730.dfy(5,11): Warning: Members with {:only} temporarily disable the verification of other members in the entire file
 git-issue-5730-include.dfy(4,9): Error: assertion might not hold
 git-issue-5730.dfy(6,11): Error: assertion might not hold
 
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-859a.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-859a.dfy.expect
index ab339eed84a..d7923e23a08 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-859a.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/git-issues/git-issue-859a.dfy.expect
@@ -1,6 +1,6 @@
 git-issue-859a.dfy(34,4): Error: The Extract member may not be ghost unless the initial LHS is ghost
 git-issue-859a.dfy(44,7): Error: a call to a ghost function is allowed only in specification contexts (consider declaring the function without the 'ghost' keyword)
-git-issue-859a.dfy(55,4): Error: return statement is not allowed in this context (because it is guarded by a specification-only expression)
+git-issue-859a.dfy(55,7): Error: return statement is not allowed in this context (because it is guarded by a specification-only expression)
 git-issue-859a.dfy(82,10): Error: Member 'IsFailure' in type 'NotFunctionsAtAll' (used indirectly via a :- statement) is expected to be a function
 git-issue-859a.dfy(82,10): Error: Member 'PropagateFailure' in type 'NotFunctionsAtAll' (used indirectly via a :- statement) is expected to be a function
 git-issue-859a.dfy(82,10): Error: Member 'Extract' in type 'NotFunctionsAtAll' (used indirectly via a :- statement) is expected to be a function
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ByProofRefactoring.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ByProofRefactoring.dfy.expect
index 948d0eaff06..8fa54588b21 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ByProofRefactoring.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ByProofRefactoring.dfy.expect
@@ -1,8 +1,8 @@
 ByProofRefactoring.dfy(11,0): Info: Consider hiding this function, which is unused by the proof: P
-ByProofRefactoring.dfy(18,2): Info: This fact was only used to prove the precondtion of the method call ByProofRefactoring.dfy(19,3). Consider moving it into a by-proof.
-ByProofRefactoring.dfy(31,2): Info: This fact was only used to prove the assertion ByProofRefactoring.dfy(32,3)-(32,13). Consider moving it into a by-proof.
+ByProofRefactoring.dfy(18,10): Info: This fact was only used to prove the precondition of the method call ByProofRefactoring.dfy(19,4). Consider moving it into a by-proof.
+ByProofRefactoring.dfy(31,10): Info: This fact was only used to prove the assertion ByProofRefactoring.dfy(32,10)-(32,12). Consider moving it into a by-proof.
 ByProofRefactoring.dfy(44,0): Info: Consider hiding this function, which is unused by the proof: P
-ByProofRefactoring.dfy(43,11): Info: This requires clause was only used to prove the assertion ByProofRefactoring.dfy(45,3)-(45,13). Consider labelling it and revealing it in a by-proof.
+ByProofRefactoring.dfy(43,12): Info: This requires clause was only used to prove the assertion ByProofRefactoring.dfy(45,10)-(45,12). Consider labelling it and revealing it in a by-proof.
 ByProofRefactoring.dfy(50,0): Info: Consider hiding this function, which is unused by the proof: P
 ByProofRefactoring.dfy(58,2): Info: This fact was only used to prove the assertion ByProofRefactoring.dfy(60,3)-(60,12). Consider moving it into a by-proof.
 
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencies.dfy_combined_limited.html.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencies.dfy_combined_limited.html.expect
index 1f42fd81bad..53730d6858a 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencies.dfy_combined_limited.html.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencies.dfy_combined_limited.html.expect
@@ -258,7 +258,7 @@ method {:testEntry} ObviouslyUnnecessaryRequiresMethod(x: nat) returns (r: nat)
   requires </span><span class="nc" id="241:12">x < 1</span><span class="na" id="241:17">0 // not required for the proof
 {
   // cause at least a little proof work to be necessary, for nat bounds
-  if (x > 5) { r</span><span class="nc" id="244:17">eturn x </span><span class="na" id="244:25">+</span><span class="nc" id="244:26"> 2;</span><span class="na" id="244:29"> } else { r</span><span class="nc" id="244:40">eturn x </span><span class="na" id="244:48">+</span><span class="nc" id="244:49"> 1;</span><span class="na" id="244:52"> }
+  if (x > 5) { return x + 2; } else { return x + 1; }
 </span><span class="nc" id="245:1">}
 
 </span><span class="na" id="247:1">// Code obviously not constrained by ensures clause.
@@ -317,8 +317,8 @@ method {:testEntry} MultiPartRedundantRequiresMethod(x: int) returns (r: int)
   requires x == 11 // implied by the previous two, but neither individually
   ensures r == 11
 {
-  r</span><span class="nc" id="303:4">eturn x;
-}
+  return x;
+</span><span class="nc" id="304:1">}
 
 </span><span class="na" id="306:1">// Contradiction between three different requires clauses, with at least one of
 // the three being partly in a separately-defined function (function and
@@ -338,8 +338,8 @@ method {:testEntry} MultiPartContradictoryRequiresMethod(x: int, y: int) returns
   requires </span><span class="nc" id="321:12">y != 1</span><span class="na" id="321:18">1 // contradicts the previous two
   ensures r == 11 // provable from first two preconditions, but shouldn't be covered
 {
-  r</span><span class="nc" id="324:4">eturn x;
-}
+  return x;
+</span><span class="nc" id="325:1">}
 
 </span><span class="na" id="327:1">function {:testEntry} ContradictoryEnsuresClauseFunc(x: int): (r: int)
   requires </span><span class="nc" id="328:12">x > 1
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencies.dfy_verification.html.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencies.dfy_verification.html.expect
index 17c0fdc81c1..3e334e1e315 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencies.dfy_verification.html.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencies.dfy_verification.html.expect
@@ -258,7 +258,7 @@ method {:testEntry} ObviouslyUnnecessaryRequiresMethod(x: nat) returns (r: nat)
   requires </span><span class="nc" id="241:12">x < 1</span><span class="na" id="241:17">0 // not required for the proof
 {
   // cause at least a little proof work to be necessary, for nat bounds
-  if (x > 5) { </span><span class="pc" id="244:16">r</span><span class="nc" id="244:17">eturn x </span><span class="pc" id="244:25">+</span><span class="nc" id="244:26"> 2;</span><span class="na" id="244:29"> } else { </span><span class="pc" id="244:39">r</span><span class="nc" id="244:40">eturn x </span><span class="pc" id="244:48">+</span><span class="nc" id="244:49"> 1;</span><span class="na" id="244:52"> }
+  if (x > 5) { </span><span class="pc" id="244:16">return x + 2;</span><span class="na" id="244:29"> } else { </span><span class="pc" id="244:39">return x + 1;</span><span class="na" id="244:52"> }
 </span><span class="nc" id="245:1">}
 
 </span><span class="na" id="247:1">// Code obviously not constrained by ensures clause.
@@ -317,8 +317,8 @@ method {:testEntry} MultiPartRedundantRequiresMethod(x: int) returns (r: int)
   requires </span><span class="pc" id="300:12">x == 1</span><span class="na" id="300:18">1 // implied by the previous two, but neither individually
   ensures </span><span class="pc" id="301:11">r == 1</span><span class="na" id="301:17">1
 {
-  </span><span class="pc" id="303:3">r</span><span class="nc" id="303:4">eturn x;
-}
+  </span><span class="pc" id="303:3">return x;
+</span><span class="nc" id="304:1">}
 
 </span><span class="na" id="306:1">// Contradiction between three different requires clauses, with at least one of
 // the three being partly in a separately-defined function (function and
@@ -338,8 +338,8 @@ method {:testEntry} MultiPartContradictoryRequiresMethod(x: int, y: int) returns
   requires </span><span class="nc" id="321:12">y != 1</span><span class="na" id="321:18">1 // contradicts the previous two
   ensures </span><span class="pc" id="322:11">r == 1</span><span class="na" id="322:17">1 // provable from first two preconditions, but shouldn't be covered
 {
-  </span><span class="pc" id="324:3">r</span><span class="nc" id="324:4">eturn x;
-}
+  </span><span class="pc" id="324:3">return x;
+</span><span class="nc" id="325:1">}
 
 </span><span class="na" id="327:1">function {:testEntry} ContradictoryEnsuresClauseFunc(x: int): (r: int)
   requires </span><span class="nc" id="328:12">x > 1
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencyLogging.dfy b/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencyLogging.dfy
index a51792b658f..bda7260cc40 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencyLogging.dfy
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencyLogging.dfy
@@ -110,8 +110,8 @@
 // CHECK:       ProofDependencies.dfy\(336,1\)-\(342,1\): function definition for CallContradictoryFunctionFunc
 // CHECK:       ProofDependencies.dfy\(337,12\)-\(337,16\): requires clause
 // CHECK:       ProofDependencies.dfy\(338,11\)-\(338,15\): ensures clause
-// CHECK:       ProofDependencies.dfy\(341,3\)-\(341,39\): function call result
 // CHECK:       ProofDependencies.dfy\(341,3\)-\(341,35\): function precondition satisfied
+// CHECK:       ProofDependencies.dfy\(341,3\)-\(341,39\): function call result
 //
 // CHECK: Results for M.CallContradictoryMethodMethod \(correctness\)
 // CHECK:     Proof dependencies:
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencyWarnings.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencyWarnings.dfy.expect
index bbf5342ab20..60b48834554 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencyWarnings.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencyWarnings.dfy.expect
@@ -1,20 +1,20 @@
-ProofDependencies.dfy(176,11): Warning: unnecessary (or partly unnecessary) assume statement
-ProofDependencies.dfy(185,11): Warning: unnecessary (or partly unnecessary) assume statement
+ProofDependencies.dfy(176,13): Warning: unnecessary (or partly unnecessary) assume statement
+ProofDependencies.dfy(185,13): Warning: unnecessary (or partly unnecessary) assume statement
 ProofDependencies.dfy(186,4): Warning: proved using contradictory assumptions: assertion always holds. (Use the `{:contradiction}` attribute on the `assert` statement to silence.)
-ProofDependencies.dfy(191,11): Warning: unnecessary (or partly unnecessary) assume statement
+ProofDependencies.dfy(191,13): Warning: unnecessary (or partly unnecessary) assume statement
 ProofDependencies.dfy(193,4): Warning: proved using contradictory assumptions: assertion always holds. (Use the `{:contradiction}` attribute on the `assert` statement to silence.)
 ProofDependencies.dfy(202,2): Warning: proved using contradictory assumptions: assertion always holds. (Use the `{:contradiction}` attribute on the `assert` statement to silence.)
 ProofDependencies.dfy(203,4): Warning: proved using contradictory assumptions: value always satisfies the subset constraints of 'nat'
-ProofDependencies.dfy(209,10): Warning: ensures clause proved using contradictory assumptions
+ProofDependencies.dfy(209,12): Warning: ensures clause proved using contradictory assumptions
 ProofDependencies.dfy(211,2): Warning: proved using contradictory assumptions: assertion always holds. (Use the `{:contradiction}` attribute on the `assert` statement to silence.)
 ProofDependencies.dfy(212,11): Warning: proved using contradictory assumptions: value always satisfies the subset constraints of 'nat'
-ProofDependencies.dfy(226,11): Warning: unnecessary requires clause
-ProofDependencies.dfy(241,11): Warning: unnecessary requires clause
-ProofDependencies.dfy(298,11): Warning: unnecessary requires clause
-ProofDependencies.dfy(299,11): Warning: unnecessary requires clause
-ProofDependencies.dfy(321,11): Warning: unnecessary requires clause
-ProofDependencies.dfy(346,10): Warning: ensures clause proved using contradictory assumptions
-ProofDependencies.dfy(354,11): Warning: unnecessary requires clause
-ProofDependencies.dfy(363,9): Warning: unnecessary (or partly unnecessary) assert statement
+ProofDependencies.dfy(226,13): Warning: unnecessary requires clause
+ProofDependencies.dfy(241,13): Warning: unnecessary requires clause
+ProofDependencies.dfy(298,13): Warning: unnecessary requires clause
+ProofDependencies.dfy(299,13): Warning: unnecessary requires clause
+ProofDependencies.dfy(321,13): Warning: unnecessary requires clause
+ProofDependencies.dfy(346,12): Warning: ensures clause proved using contradictory assumptions
+ProofDependencies.dfy(354,19): Warning: unnecessary requires clause
+ProofDependencies.dfy(363,15): Warning: unnecessary (or partly unnecessary) assert statement
 
 Dafny program verifier finished with 32 verified, 0 errors
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencyWarnings.dfy.expect2 b/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencyWarnings.dfy.expect2
index ad7ef92c378..902206d7e1a 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencyWarnings.dfy.expect2
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/logger/ProofDependencyWarnings.dfy.expect2
@@ -1,21 +1,21 @@
 Warning: this way of using the CLI is deprecated. Use 'dafny --help' to see help for the new Dafny CLI format
-ProofDependencies.dfy(176,11): Warning: unnecessary (or partly unnecessary) assume statement
-ProofDependencies.dfy(185,11): Warning: unnecessary (or partly unnecessary) assume statement
+ProofDependencies.dfy(176,13): Warning: unnecessary (or partly unnecessary) assume statement
+ProofDependencies.dfy(185,13): Warning: unnecessary (or partly unnecessary) assume statement
 ProofDependencies.dfy(186,4): Warning: proved using contradictory assumptions: assertion always holds. (Use the `{:contradiction}` attribute on the `assert` statement to silence.)
-ProofDependencies.dfy(191,11): Warning: unnecessary (or partly unnecessary) assume statement
+ProofDependencies.dfy(191,13): Warning: unnecessary (or partly unnecessary) assume statement
 ProofDependencies.dfy(193,4): Warning: proved using contradictory assumptions: assertion always holds. (Use the `{:contradiction}` attribute on the `assert` statement to silence.)
 ProofDependencies.dfy(202,2): Warning: proved using contradictory assumptions: assertion always holds. (Use the `{:contradiction}` attribute on the `assert` statement to silence.)
 ProofDependencies.dfy(203,4): Warning: proved using contradictory assumptions: value always satisfies the subset constraints of 'nat'
-ProofDependencies.dfy(209,10): Warning: ensures clause proved using contradictory assumptions
+ProofDependencies.dfy(209,12): Warning: ensures clause proved using contradictory assumptions
 ProofDependencies.dfy(211,2): Warning: proved using contradictory assumptions: assertion always holds. (Use the `{:contradiction}` attribute on the `assert` statement to silence.)
 ProofDependencies.dfy(212,11): Warning: proved using contradictory assumptions: value always satisfies the subset constraints of 'nat'
-ProofDependencies.dfy(226,11): Warning: unnecessary requires clause
-ProofDependencies.dfy(241,11): Warning: unnecessary requires clause
-ProofDependencies.dfy(298,11): Warning: unnecessary requires clause
-ProofDependencies.dfy(299,11): Warning: unnecessary requires clause
-ProofDependencies.dfy(321,11): Warning: unnecessary requires clause
-ProofDependencies.dfy(346,10): Warning: ensures clause proved using contradictory assumptions
-ProofDependencies.dfy(354,11): Warning: unnecessary requires clause
-ProofDependencies.dfy(363,9): Warning: unnecessary (or partly unnecessary) assert statement
+ProofDependencies.dfy(226,13): Warning: unnecessary requires clause
+ProofDependencies.dfy(241,13): Warning: unnecessary requires clause
+ProofDependencies.dfy(298,13): Warning: unnecessary requires clause
+ProofDependencies.dfy(299,13): Warning: unnecessary requires clause
+ProofDependencies.dfy(321,13): Warning: unnecessary requires clause
+ProofDependencies.dfy(346,12): Warning: ensures clause proved using contradictory assumptions
+ProofDependencies.dfy(354,19): Warning: unnecessary requires clause
+ProofDependencies.dfy(363,15): Warning: unnecessary (or partly unnecessary) assert statement
 
 Dafny program verifier finished with 32 verified, 0 errors
diff --git a/Source/IntegrationTests/TestFiles/LitTests/LitTest/separate-verification/assumptions.dfy.expect b/Source/IntegrationTests/TestFiles/LitTests/LitTest/separate-verification/assumptions.dfy.expect
index 0983351f342..b8547fe4073 100644
--- a/Source/IntegrationTests/TestFiles/LitTests/LitTest/separate-verification/assumptions.dfy.expect
+++ b/Source/IntegrationTests/TestFiles/LitTests/LitTest/separate-verification/assumptions.dfy.expect
@@ -1,11 +1,11 @@
-TestAuditor.dfy(24,25): Warning: This ensures clause is part of a bodyless method. Add the {:axiom} attribute to it or the enclosing method to suppress this warning
+TestAuditor.dfy(24,10): Warning: This ensures clause is part of a bodyless method. Add the {:axiom} attribute to it or the enclosing method to suppress this warning
 TestAuditor.dfy(38,2): Warning: assume statement has no {:axiom} annotation
 TestAuditor.dfy(45,17): Warning: when a method is imported, meaning it has no body and an {:extern} annotation, Dafny can not guarantee that its implementation satisfies its post-conditions (its ensures clauses and outputs that are subset types). To silence this warning, please add an {:axiom} attribute or use the option '--allow-external-contracts'.
 TestAuditor.dfy(50,17): Warning: when a method is exported, meaning it has a body and an {:extern} annotation, Dafny can not guarantee that it is called with arguments that satisfy its preconditions (its requires clauses and inputs that are subset types). To silence this warning, please add an {:axiom} attribute or use the option '--allow-external-contracts'
 TestAuditor.dfy(72,19): Warning: when a function is imported, meaning it has no body and an {:extern} annotation, Dafny can not guarantee that its implementation satisfies its post-conditions (its ensures clauses and outputs that are subset types). To silence this warning, please add an {:axiom} attribute or use the option '--allow-external-contracts'.
 TestAuditor.dfy(136,2): Warning: assume statement has no {:axiom} annotation
-TestAuditor.dfy(150,9): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
-TestAuditor.dfy(154,7): Warning: Members with {:only} temporarily disable the verification of other members in the entire file
+TestAuditor.dfy(150,11): Warning: Assertion with {:only} temporarily transforms other assertions into assumptions
+TestAuditor.dfy(154,9): Warning: Members with {:only} temporarily disable the verification of other members in the entire file
 TestAuditor.dfy(95,4): Warning: this forall statement has no body
 TestAuditor.dfy(102,4): Warning: this loop has no body (loop frame: i)
 TestAuditor.dfy(139,2): Warning: this forall statement has no body