Cleanups

Author: odersky

compiler/src/dotty/tools/dotc/printing/PlainPrinter.scala

@@ -505,7 +505,7 @@ class PlainPrinter(_ctx: Context) extends Printer {
         case _: DivergingImplicit => "Diverging Implicit"
         case _: ShadowedImplicit => "Shadowed Implicit"
         case result: AmbiguousImplicits =>
-          "Ambiguous Implicit: " ~ toText(result.alt1) ~ " and " ~ toText(result.alt2)
+          "Ambiguous Implicit: " ~ toText(result.alt1.ref) ~ " and " ~ toText(result.alt2.ref)
         case _ =>
           "?Unknown Implicit Result?" + result.getClass
     }

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

@@ -1195,9 +1195,6 @@ trait Applications extends Compatibility { self: Typer with Dynamic =>
       if (winsType2) -1 else 0
   }}
 
-  def isAsGood(alt1: TermRef, alt2: TermRef, nesting1: Int = 0, nesting2: Int = 0)(implicit ctx: Context): Boolean =
-    compare(alt1, alt2, nesting1, nesting2) >= 0
-
   def narrowMostSpecific(alts: List[TermRef])(implicit ctx: Context): List[TermRef] = track("narrowMostSpecific") {
     alts match {
       case Nil => alts

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

@@ -30,7 +30,7 @@ import reporting.diagnostic.{Message, MessageContainer}
 import Inferencing.fullyDefinedType
 import Trees._
 import Hashable._
-import util.{Property, PriorityGraph}
+import util.Property
 import config.Config
 import config.Printers.{implicits, implicitsDetailed, typr}
 import collection.mutable

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

@@ -2267,7 +2267,7 @@ class Typer extends Namer with TypeAssigner with Applications with Implicits wit
           case SearchSuccess(inferred, _, _) =>
             adapt(inferred, pt)(ctx.retractMode(Mode.ImplicitsEnabled))
           case failure: SearchFailure =>
-            if (pt.isInstanceOf[ProtoType] && !failure.reason.isInstanceOf[AmbiguousImplicits])
+            if (pt.isInstanceOf[ProtoType] && !failure.isAmbiguous)
               // don't report the failure but return the tree unchanged. This
               // will cause a failure at the next level out, which usually gives
               // a better error message.