diff --git a/src/dotty/tools/dotc/printing/RefinedPrinter.scala b/src/dotty/tools/dotc/printing/RefinedPrinter.scala index ca62827afe4a..bdfce266ca5e 100644 --- a/src/dotty/tools/dotc/printing/RefinedPrinter.scala +++ b/src/dotty/tools/dotc/printing/RefinedPrinter.scala @@ -96,15 +96,15 @@ class RefinedPrinter(_ctx: Context) extends PlainPrinter(_ctx) { override def toText(tp: Type): Text = controlled { def toTextTuple(args: List[Type]): Text = - "(" ~ toTextGlobal(args, ", ") ~ ")" + "(" ~ Text(args.map(argText), ", ") ~ ")" def toTextFunction(args: List[Type]): Text = changePrec(GlobalPrec) { val argStr: Text = if (args.length == 2 && !defn.isTupleType(args.head)) - atPrec(InfixPrec) { toText(args.head) } + atPrec(InfixPrec) { argText(args.head) } else toTextTuple(args.init) - argStr ~ " => " ~ toText(args.last) + argStr ~ " => " ~ argText(args.last) } homogenize(tp) match { case AppliedType(tycon, args) => diff --git a/src/dotty/tools/dotc/typer/Typer.scala b/src/dotty/tools/dotc/typer/Typer.scala index 11a7b6753059..df72f009537a 100644 --- a/src/dotty/tools/dotc/typer/Typer.scala +++ b/src/dotty/tools/dotc/typer/Typer.scala @@ -582,7 +582,10 @@ class Typer extends Namer with TypeAssigner with Applications with Implicits wit private def decomposeProtoFunction(pt: Type, defaultArity: Int)(implicit ctx: Context): (List[Type], Type) = pt match { case _ if defn.isFunctionType(pt) => - (pt.dealias.argInfos.init, pt.dealias.argInfos.last) + // if expected parameter type(s) are wildcards, approximate from below. + // if expected result type is a wildcard, approximate from above. + // this can type the greatest set of admissible closures. + (pt.dealias.argTypesLo.init, pt.dealias.argTypesHi.last) case SAMType(meth) => val mt @ MethodType(_, paramTypes) = meth.info (paramTypes, mt.resultType) diff --git a/tests/pos/conformsWild.scala b/tests/pos/conformsWild.scala new file mode 100644 index 000000000000..cfc10d92df47 --- /dev/null +++ b/tests/pos/conformsWild.scala @@ -0,0 +1,11 @@ +object Test { + + val x: Function1[_, _] = (x: String) => 1 + + val y: Function1[_, _] = x => 1 + val y0: Function1[_, _] = x => x + val y1: Function1[_, Nothing] = x => x + + val z: (_, _) = (1, 2) + +}