[Compiler] Refactoring.

git-svn-id: https://nemerle.googlecode.com/svn/nemerle/trunk@9907 c8a6711f-211a-0410-a8d5-2f220496d6d1

Author: someone-with-default-username

ncc/typing/Typer-PatternTyper.n

@@ -358,33 +358,28 @@ namespace Nemerle.Compiler
         }
         else match (matched_value_type.Hint) 
         {
-          // if we expecte to match on a class, transform the pattern
+          // if we expect matching on a class, transform the pattern
           // to include field names
           | Some (FixedType.Class (ti, _)) =>
             def flags = BindingFlags.DeclaredOnly %| BindingFlags.Public %| BindingFlags.Instance;
             def mems  = ti.GetFields(flags).Filter(withoutIgnoreFieldAttribute);
             def names = mems.Map(_.Name);
-            if (names.Length == pats.Length)
+            match(pats.Length)
             {
-              if (pats.Length == 0)
-              {
-                ReportError(messenger, "pattern can't matchs 0 values.");
+              | 0 =>
+                ReportError(messenger, "pattern can't match 0 values");
                 Pattern.Error()
-              }
-              else
-              {
+
+              | n when n == names.Length =>
                 def assigns = NList.Map2(names, pats, (n, p) => PT.PExpr.Assign (PT.PExpr.Ref(PT.Name(n)), p));
                 TypeTuplePattern(matched_value_type, assigns)
-              }
-            }
-            else
-            {
-              ReportError(messenger, $"pattern matches $(pats.Length) values, while the type `$(ti)' has $(names.Length) fields");
-              Pattern.Error()
+
+              | n =>
+                ReportError(messenger, $"pattern matches $n values, while the type `$ti' has $(names.Length) fields");
+                Pattern.Error()
             }
-            
-          | Some (FixedType.Tuple (types)) 
-            when types.Length != pats.Length =>
+
+          | Some (FixedType.Tuple (types)) when types.Length != pats.Length =>
             ReportError (messenger,
                          $ "pattern matches $(pats.Length)-tuples, "
                            "while the value matched is a "