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-rw-r--r--test/pending/run/reify_callccinterpreter.scala94
1 files changed, 94 insertions, 0 deletions
diff --git a/test/pending/run/reify_callccinterpreter.scala b/test/pending/run/reify_callccinterpreter.scala
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index 0000000000..c10f4f0b4e
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+++ b/test/pending/run/reify_callccinterpreter.scala
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+import scala.tools.nsc.reporters._
+import scala.tools.nsc.Settings
+import reflect.runtime.Mirror.ToolBox
+
+object Test extends App {
+ val code = scala.reflect.Code.lift{
+ type Answer = Value;
+
+ /**
+ * A continuation monad.
+ */
+ case class M[A](in: (A => Answer) => Answer) {
+ def bind[B](k: A => M[B]) = M[B](c => in (a => k(a) in c))
+ def map[B](f: A => B): M[B] = bind(x => unitM(f(x)))
+ def flatMap[B](f: A => M[B]): M[B] = bind(f)
+ }
+
+ def unitM[A](a: A) = M[A](c => c(a))
+
+ def id[A] = (x: A) => x
+ def showM(m: M[Value]): String = (m in id).toString()
+
+ def callCC[A](h: (A => M[A]) => M[A]) =
+ M[A](c => h(a => M[A](d => c(a))) in c)
+
+ type Name = String
+
+ trait Term
+ case class Var(x: Name) extends Term
+ case class Con(n: Int) extends Term
+ case class Add(l: Term, r: Term) extends Term
+ case class Lam(x: Name, body: Term) extends Term
+ case class App(fun: Term, arg: Term) extends Term
+ case class Ccc(x: Name, t: Term) extends Term
+
+ trait Value
+ case object Wrong extends Value {
+ override def toString() = "wrong"
+ }
+ case class Num(n: Int) extends Value {
+ override def toString() = n.toString()
+ }
+ case class Fun(f: Value => M[Value]) extends Value {
+ override def toString() = "<function>"
+ }
+
+ type Environment = List[Pair[Name, Value]];
+
+ def lookup(x: Name, e: Environment): M[Value] = e match {
+ case List() => unitM(Wrong)
+ case Pair(y, b) :: e1 => if (x == y) unitM(b) else lookup(x, e1)
+ }
+
+ def add(a: Value, b: Value): M[Value] = Pair(a, b) match {
+ case Pair(Num(m), Num(n)) => unitM(Num(m + n))
+ case _ => unitM(Wrong)
+ }
+
+ def apply(a: Value, b: Value): M[Value] = a match {
+ case Fun(k) => k(b)
+ case _ => unitM(Wrong)
+ }
+
+ def interp(t: Term, e: Environment): M[Value] = t match {
+ case Var(x) => lookup(x, e)
+ case Con(n) => unitM(Num(n))
+ case Add(l, r) => for (a <- interp(l, e);
+ b <- interp(r, e);
+ c <- add(a, b))
+ yield c
+ case Lam(x, t) => unitM(Fun(a => interp(t, Pair(x, a) :: e)))
+ case App(f, t) => for (a <- interp(f, e);
+ b <- interp(t, e);
+ c <- apply(a, b))
+ yield c
+ case Ccc(x, t) => callCC(k => interp(t, Pair(x, Fun(k)) :: e))
+ }
+
+ def test(t: Term): String = showM(interp(t, List()))
+
+ val term0 = App(Lam("x", Add(Var("x"), Var("x"))), Add(Con(10), Con(11)))
+ val term1 = App(Con(1), Con(2))
+ val term2 = Add(Con(1), Ccc("k", Add(Con(2), App(Var("k"), Con(4)))))
+
+ println(test(term0))
+ println(test(term1))
+ println(test(term2))
+ };
+
+ val reporter = new ConsoleReporter(new Settings)
+ val toolbox = new ToolBox(reporter)
+ val ttree = toolbox.typeCheck(code.tree)
+ toolbox.runExpr(ttree)
+}