Generate Fruit

core/src/main/scala/pl/writeonly/catculus/adt/calculus/Fruit.scala

@@ -0,0 +1,31 @@
+package pl.writeonly.catculus.adt.calculus
+
+import pl.writeonly.catculus.adt.calculus.Combinator.generateC
+import pl.writeonly.catculus.adt.tree.BinaryTree
+import pl.writeonly.catculus.adt.tree.BinaryTree.{Leaf, Node}
+import spire.math.Natural
+
+object Fruit {
+
+  def generateFruitBT(tree: BinaryTree[Fruit]): String = tree match {
+    case Leaf(a) => generateFruit(a)
+    case Node(a, b) => s"`${generateFruitBT(a)} ${generateFruitBT(b)}"
+  }
+
+  def generateFruit(f: Fruit): String = f match {
+    case Com(c) => generateC(c)
+    case Nat(n) => s"$n "
+    case Succ   => ":"
+  }
+
+  def fromLambda(l: Lambda): BinaryTree[Fruit] = l match {
+    case Lambda.Com(c)    => Leaf(Com(c))
+    case Lambda.App(f, x) => Node(fromLambda(f), fromLambda(x))
+  }
+
+  final case class Com(c: Combinator) extends Fruit
+  final case class Nat(n: Natural) extends Fruit
+  final case object Succ extends Fruit
+}
+
+sealed trait Fruit

core/src/main/scala/pl/writeonly/catculus/adt/calculus/Lambda.scala

@@ -0,0 +1,72 @@
+package pl.writeonly.catculus.adt.calculus
+
+import cats.data.NonEmptyList
+import pl.writeonly.catculus.Extras.fix
+import pl.writeonly.catculus.adt.tree.BinaryTree
+import pl.writeonly.catculus.adt.tree.BinaryTree._
+import spire.math.Natural
+
+object Lambda {
+
+  //  val thrushVariable: Lambda = Var(";")
+  val vireoVariable: Lambda = Var(",")
+  val nilVariable: Lambda = Var(".")
+  val succVariable: Lambda = Var(":")
+  val zeroVariable: Lambda = Var("0")
+  val falseVariable: Lambda = Var("false")
+  val trueVariable: Lambda = Var("true")
+
+  //  def wrapAppThrush(name: String, l1: Lambda, l2: Lambda): Lambda = App(thrushVariable, App(l1, Abs(name, l2)))
+  def wrapAppVireoApp(l1: Lambda, l2: Lambda): Lambda = App(App (vireoVariable, l1), l2)
+  def appSuccVariable(l: Lambda): Lambda = App(succVariable, l)
+
+  def generate(l: Lambda): String = l match {
+    case Com(c)         => Combinator.generateC(c)
+    case Var(n)         => n
+    case Abs(n, f)      => s"\\$n ${generate(f)}"
+    case App(f, x)      => s"`${generate(f)} ${generate(x)}"
+    case MultiApp(fs)   => s"(${fs.map(generate).toList.mkString(" ")})"
+    case LocalScope(fs) => s"{${fs.map(generate).toList.mkString(" ")}}"
+    case NilList(fs)    => s"[${fs.map(generate).mkString(" ")}]"
+    case CharStr(s)     => s"\"$s\""
+    case NatNum(n)      => n.toString
+    case IntNum(s, n)   => Sign.generate(s) + n.toString
+  }
+
+  def toCombinators(l: Lambda): BinaryTree[Combinator] = l match {
+    case Com(c) => Leaf(c)
+    case App(f, x) => Node(toCombinators(f), toCombinators(x))
+  }
+
+//  def apps1(head: Lambda, tail: List[Lambda]): Lambda = Apps(NonEmptyList(head, tail))
+
+  //I know it is crazy, but I wanted to check it is possible
+  private val isOnlyCombinatorStep: (Lambda => Boolean) => Lambda => Boolean = rec => {
+    case Com(_) => true
+    case App(f, g) => rec(f) && rec(g)
+    case _ => false
+  }
+
+  //I know it is crazy, but I wanted to check it is possible
+  val isOnlyCombinator: Lambda => Boolean = fix(isOnlyCombinatorStep)
+
+  def multi1(head: Lambda, tail: List[Lambda]): Lambda = MultiApp(NonEmptyList(head, tail))
+  def local1(head: Lambda, tail: List[Lambda]): Lambda = LocalScope(NonEmptyList(head, tail))
+
+  def natNumFromString(s: String): Lambda = NatNum(Natural(s))
+
+  def intNumFromString(sing: Sign, s: String): Lambda = IntNum(sing, Natural(s))
+
+  final case class Com(c: Combinator) extends Lambda
+  final case class Var(name: String) extends Lambda
+  final case class Abs(param: String, body: Lambda) extends Lambda
+  final case class App(f: Lambda, x: Lambda) extends Lambda
+  final case class MultiApp(fs: NonEmptyList[Lambda]) extends Lambda
+  final case class LocalScope(xs: NonEmptyList[Lambda])extends Lambda
+  final case class NilList(xs: List[Lambda]) extends Lambda
+  final case class CharStr(s: String) extends Lambda
+  final case class NatNum(n: Natural) extends Lambda
+  final case class IntNum(s: Sign, n: Natural) extends Lambda
+}
+
+sealed trait Lambda

core/src/main/scala/pl/writeonly/catculus/interpreter/FruitInterpreter.scala

@@ -0,0 +1,7 @@
+package pl.writeonly.catculus.interpreter
+
+object FruitInterpreter {
+
+
+
+}

core/src/test/scala/pl/writeonly/catculus/adt/calculus/LambdaSpec.scala

@@ -0,0 +1,75 @@
+package pl.writeonly.catculus.adt.calculus
+
+import org.scalatest.prop.TableFor3
+import pl.writeonly.catculus.TableDrivenPropertySpec
+import pl.writeonly.catculus.adt.calculus.Lambda._
+import pl.writeonly.catculus.parsers.LambdaParser
+import pl.writeonly.catculus.reducer.AbstractionReducer.reduceAbstraction
+import pl.writeonly.catculus.reducer.SugarReducer.reduceSugar
+
+class LambdaSpec extends TableDrivenPropertySpec {
+
+  val basicLambda: TableFor3[String, Lambda, String] = Table(
+    ("lambda", "ast", "combinators"),
+    ("a", Var("a"), "a"),
+    ("\\a a", Abs("a", Var("a")), "I"),
+    ("`a a", App(Var("a"), Var("a")), "`a a"),
+    ("\\a `a a", Abs("a", App(Var("a"), Var("a"))), "``S I I"),
+    ("\\a \\a a", Abs("a", Abs("a", Var("a"))), "`K I"),
+    ("\\a \\b `a b", Abs("a", Abs("b", App(Var("a"), Var("b")))), "``S ``S `K S ``S `K K I `K I"),
+    ("\\a \\b `b a", Abs("a", Abs("b", App(Var("b"), Var("a")))), "``S `K `S I ``S `K K I"),
+  )
+
+  val advancedLambda: TableFor3[String, String, String] =
+    Table(
+      ("lambda", "desugared", "combinators"),
+      ("(a a)", "`a a", "`a a"),
+      ("((a a))", "`a a", "`a a"),
+      ("(a b c)", "``a b c", "``a b c"),
+      ("{a b c}", "``a b c", "``a b c"),
+      ("{; (a b) \\c (c d)}", "``; `a b \\c `c d", "``; `a b ``S I `K d"),
+      ("(, a .)", "``, a .", "``, a ."),
+      ("(, a (, b .))", "``, a ``, b .", "``, a ``, b ."),
+      ("[]", ".", "."),
+      ("[a]", "``, a .", "``, a ."),
+      ("[a b]", "``, a ``, b .", "``, a ``, b ."),
+      ("\"\"", ".", "."),
+      ("\" \"", "``, , ``, `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: 0 .", "``, , ``, `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: `: 0 ."),
+      ("0", "0", "0"),
+      ("1", "`: 0", "`: 0"),
+      ("+0", "``, false 0", "``, false 0"),
+      ("-0", "``, true 0", "``, true 0"),
+      ("+1", "``, false `: 0", "``, false `: 0"),
+      ("-1", "``, true `: 0", "``, true `: 0"),
+    )
+
+  it should "parse basic Lambda and save ATS" in {
+    forAll(basicLambda) { (lambda, ast, _) =>
+      LambdaParser.parse(lambda).value shouldBe ast
+    }
+  }
+
+  it should "compile basic Lambda" in {
+    forAll(basicLambda) { (lambda, _, combinators) =>
+      LambdaParser.parse(lambda).map(reduceSugar).map(reduceAbstraction).map(generate).value shouldBe combinators
+    }
+  }
+
+  it should "parse advanced Lambda" in {
+    forAll(advancedLambda) { (lambda, _, _) =>
+      LambdaParser.parse(lambda).map(generate).value shouldBe lambda
+    }
+  }
+
+  it should "desugar advanced Lambda" in {
+    forAll(advancedLambda) { (lambda, desugared, _) =>
+      LambdaParser.parse(lambda).map(reduceSugar).map(generate).value shouldBe desugared
+    }
+  }
+
+  it should "compile advanced Lambda" in {
+    forAll(advancedLambda) { (sugar, _, combinators) =>
+      LambdaParser.parse(sugar).map(reduceSugar).map(reduceAbstraction).map(generate).value shouldBe combinators
+    }
+  }
+}