Streamlining skolemization, specialization.

Skolemization code doesn't belong in Typers.  I carved
out a little place for it.  Also simplifications in
specialization.

2 files changed, 6 insertions, 37 deletions

diff --git a/src/compiler/scala/tools/nsc/typechecker/Namers.scala b/src/compiler/scala/tools/nsc/typechecker/Namers.scala
index 51542ec757..3347d2e767 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Namers.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Namers.scala
@@ -1299,7 +1299,7 @@ trait Namers extends MethodSynthesis {
         catch typeErrorHandler(tree, ErrorType)
 
       result match {
-        case PolyType(tparams @ (tp :: _), _) if tp.owner.isTerm => typer.deskolemizeTypeParams(tparams)(result)
+        case PolyType(tparams @ (tp :: _), _) if tp.owner.isTerm => deskolemizeTypeParams(tparams)(result)
         case _                                                   => result
       }
     }
@@ -1439,8 +1439,11 @@ trait Namers extends MethodSynthesis {
     private val ownerSym    = owner.symbol
     override val typeParams = tparams map (_.symbol) //@M
     override val tree       = restp.tree
-    if (ownerSym.isTerm)
-      typer skolemizeTypeParams tparams
+
+    if (ownerSym.isTerm) {
+      val skolems = deriveFreshSkolems(tparams map (_.symbol))
+      map2(tparams, skolems)(_ setSymbol _)
+    }
 
     def completeImpl(sym: Symbol) = {
       // @M an abstract type's type parameters are entered.
diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
index 17c0bdf304..1c1f35aac2 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Typers.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
@@ -3036,40 +3036,6 @@ trait Typers extends Modes with Adaptations with PatMatVirtualiser {
       packSymbols(localSyms.toList, normalizedTpe)
     }
 
-    /** Replace type parameters with their TypeSkolems, which can later
-     *  be deskolemized to the original type param. (A skolem is a
-     *  representation of a bound variable when viewed inside its scope)
-     *  !!!Adriaan: this does not work for hk types.
-     */
-    def skolemizeTypeParams(tparams: List[TypeDef]): List[TypeDef] = {
-      class Deskolemizer extends LazyType {
-        override val typeParams = tparams map (_.symbol)
-        val typeSkolems  = typeParams map (_.newTypeSkolem setInfo this)
-        // Replace the symbols
-        def substitute() = map2(tparams, typeSkolems)(_ setSymbol _)
-        override def complete(sym: Symbol) {
-          // The info of a skolem is the skolemized info of the
-          // actual type parameter of the skolem
-          sym setInfo sym.deSkolemize.info.substSym(typeParams, typeSkolems)
-        }
-      }
-      (new Deskolemizer).substitute()
-    }
-    /** Convert to corresponding type parameters all skolems of method
-     *  parameters which appear in `tparams`.
-     */
-    def deskolemizeTypeParams(tparams: List[Symbol])(tp: Type): Type = {
-      class DeSkolemizeMap extends TypeMap {
-        def apply(tp: Type): Type = tp match {
-          case TypeRef(pre, sym, args) if sym.isTypeSkolem && (tparams contains sym.deSkolemize) =>
-            mapOver(typeRef(NoPrefix, sym.deSkolemize, args))
-          case _ =>
-            mapOver(tp)
-        }
-      }
-      new DeSkolemizeMap mapOver tp
-    }
-
     def typedClassOf(tree: Tree, tpt: Tree, noGen: Boolean = false) =
       if (!checkClassType(tpt, true, false) && noGen) tpt
       else atPos(tree.pos)(gen.mkClassOf(tpt.tpe))