diff options
Diffstat (limited to 'src')
-rw-r--r-- | src/compiler/scala/tools/nsc/transform/patmat/MatchTranslation.scala | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/src/compiler/scala/tools/nsc/transform/patmat/MatchTranslation.scala b/src/compiler/scala/tools/nsc/transform/patmat/MatchTranslation.scala index 5ddcd3528b..2ebd01f091 100644 --- a/src/compiler/scala/tools/nsc/transform/patmat/MatchTranslation.scala +++ b/src/compiler/scala/tools/nsc/transform/patmat/MatchTranslation.scala @@ -57,9 +57,11 @@ trait MatchTranslation extends CpsPatternHacks { trait MatchTranslator extends TreeMakers { import typer.context + case class BoundTree(binder: Symbol, tree: Tree) + // a list of TreeMakers that encode `patTree`, and a list of arguments for recursive invocations of `translatePattern` to encode its subpatterns - private case class TranslationStep(makers: List[TreeMaker], subpatterns: List[(Symbol, Tree)]) { - def merge(f: (Symbol, Tree) => List[TreeMaker]): List[TreeMaker] = makers ::: (subpatterns flatMap f.tupled) + private case class TranslationStep(makers: List[TreeMaker], subpatterns: List[BoundTree]) { + def merge(f: BoundTree => List[TreeMaker]): List[TreeMaker] = makers ::: (subpatterns flatMap f) } // Why is it so difficult to say "here's a name and a context, give me any @@ -247,13 +249,14 @@ trait MatchTranslation extends CpsPatternHacks { translatePattern(scrutSym, pattern) ++ translateGuard(guard) :+ translateBody(body, pt) } + def translatePattern(bound: BoundTree): List[TreeMaker] = translatePattern(bound.binder, bound.tree) def translatePattern(patBinder: Symbol, patTree: Tree): List[TreeMaker] = { val pos = patTree.pos def patType = patBinder.info.dealiasWiden // the type of the variable bound to the pattern def glbWithBinder(other: Type) = glb(patType :: other :: Nil).normalize - def withSubPats(treeMakers: List[TreeMaker], subpats: (Symbol, Tree)*): TranslationStep = TranslationStep(treeMakers, subpats.toList) + def withSubPats(treeMakers: List[TreeMaker], subpats: BoundTree*): TranslationStep = TranslationStep(treeMakers, subpats.toList) def noFurtherSubPats(treeMakers: TreeMaker*): TranslationStep = TranslationStep(treeMakers.toList, Nil) def translateExtractorPattern(extractor: ExtractorCall): TranslationStep = { @@ -349,7 +352,7 @@ trait MatchTranslation extends CpsPatternHacks { case WildcardPattern() => none() case _: UnApply | _: Apply => translateExtractorPattern(ExtractorCall(patTree)) case MaybeBoundTyped(subPatBinder, pt) => one(TypeTestTreeMaker(subPatBinder, patBinder, pt, glbWithBinder(pt))(pos)) - case Bound(subpatBinder, p) => withSubPats(List(SubstOnlyTreeMaker(subpatBinder, patBinder)), (patBinder, p)) + case Bound(subpatBinder, p) => withSubPats(List(SubstOnlyTreeMaker(subpatBinder, patBinder)), BoundTree(patBinder, p)) case Literal(Constant(_)) | Ident(_) | Select(_, _) | This(_) => one(EqualityTestTreeMaker(patBinder, patTree, pos)) case Alternative(alts) => one(AlternativesTreeMaker(patBinder, alts map (translatePattern(patBinder, _)), alts.head.pos)) case Bind(_, _) => devWarning(s"Bind tree with unbound symbol $patTree") ; none() @@ -472,7 +475,7 @@ trait MatchTranslation extends CpsPatternHacks { (binders, subPatTypes).zipped map setVarInfo } - lazy val subBindersAndPatterns: List[(Symbol, Tree)] = subPatBinders zip unboundArgs + lazy val subBindersAndPatterns: List[BoundTree] = (subPatBinders, unboundArgs).zipped map BoundTree private def unboundArgs = args map unBound private def unBound(t: Tree): Tree = t match { @@ -724,9 +727,8 @@ trait MatchTranslation extends CpsPatternHacks { object Bound { def unapply(t: Tree): Option[(Symbol, Tree)] = t match { - case t@Bind(n, p) if (t.symbol ne null) && (t.symbol ne NoSymbol) => // pos/t2429 does not satisfy these conditions - Some((t.symbol, p)) - case _ => None + case t@Bind(n, p) if (t.symbol ne null) && (t.symbol ne NoSymbol) => Some((t.symbol, p)) // pos/t2429 does not satisfy these conditions + case _ => None } } } |