Polishings

Author: odersky

compiler/src/dotty/tools/dotc/config/Config.scala

@@ -148,7 +148,7 @@ object Config {
   final val showCompletions = false
 
   /** If set, enables tracing */
-  final val tracingEnabled = true
+  final val tracingEnabled = false
 
   /** Initial capacity of uniques HashMap.
    *  Note: This MUST BE a power of two to work with util.HashSet

compiler/src/dotty/tools/dotc/core/TyperState.scala

@@ -12,7 +12,6 @@ import printing.Texts._
 import config.Config
 import collection.mutable
 import java.lang.ref.WeakReference
-import Decorators._
 
 class TyperState(previous: TyperState /* | Null */) extends DotClass with Showable {
 
@@ -30,11 +29,11 @@ class TyperState(previous: TyperState /* | Null */) extends DotClass with Showab
 
   def constraint = myConstraint
   def constraint_=(c: Constraint)(implicit ctx: Context) = {
-//      println(i"assigning $c to $hashesStr")
     if (Config.debugCheckConstraintsClosed && isGlobalCommittable) c.checkClosed()
     myConstraint = c
   }
 
+  /** Reset constraint to `c` and mark current constraint as retracted if it differs from `c` */
   def resetConstraintTo(c: Constraint) = {
     if (c `ne` myConstraint) myConstraint.markRetracted()
     myConstraint = c

compiler/src/dotty/tools/dotc/typer/ProtoTypes.scala

@@ -195,10 +195,9 @@ object ProtoTypes {
 
     override def notApplied = WildcardType
 
-    /** Forget the types of any arguments that have been typed producing a constraint that is
-     *  either
-     *    - in a typer state that is not yet committed into the one of the current context `ctx`, or
-     *    - has been retracted from its typestate because oif a failed operation.
+    /** Forget the types of any arguments that have been typed producing a constraint
+     *    - that is in a typer state that is not yet committed into the one of the current context `ctx`,
+     *    - or that has been retracted from its typestate because oif a failed operation.
      *  This is necessary to avoid "orphan" TypeParamRefs that are referred to from
      *  type variables in the typed arguments, but that are not registered in the
      *  current constraint. Test cases are pos/t1756.scala and pos/i3538.scala.
@@ -208,6 +207,7 @@ object ProtoTypes {
       evalState foreachBinding { (arg, tstateConstr) =>
         if ((tstateConstr._1.uncommittedAncestor.constraint `ne` ctx.typerState.constraint) ||
             tstateConstr._2.isRetracted) {
+          typr.println(i"need to invalidate $arg / ${myTypedArg(arg)}, ${tstateConstr._2}, current = ${ctx.typerState.constraint}")
           myTypedArg = myTypedArg.remove(arg)
           evalState = evalState.remove(arg)
         }