diff options
Diffstat (limited to 'src/compiler/scala/tools/nsc/typechecker/Implicits.scala')
| -rw-r--r-- | src/compiler/scala/tools/nsc/typechecker/Implicits.scala | 36 |
1 files changed, 30 insertions, 6 deletions
diff --git a/src/compiler/scala/tools/nsc/typechecker/Implicits.scala b/src/compiler/scala/tools/nsc/typechecker/Implicits.scala index a34e97b6cb..bee2ae8e99 100644 --- a/src/compiler/scala/tools/nsc/typechecker/Implicits.scala +++ b/src/compiler/scala/tools/nsc/typechecker/Implicits.scala @@ -34,14 +34,33 @@ trait Implicits { import typingStack.{ printTyping } import typeDebug._ + // standard usage + def inferImplicitFor(pt: Type, tree: Tree, context: Context, reportAmbiguous: Boolean = true): SearchResult = + inferImplicit(tree, pt, reportAmbiguous, isView = false, context, saveAmbiguousDivergent = true, tree.pos) + + // used by typer to find an implicit coercion + def inferImplicitView(from: Type, to: Type, tree: Tree, context: Context, reportAmbiguous: Boolean, saveAmbiguousDivergent: Boolean) = + inferImplicit(tree, Function1(from, to), reportAmbiguous, isView = true, context, saveAmbiguousDivergent, tree.pos) + + // used for manifests, typetags, checking language features, scaladoc + def inferImplicitByType(pt: Type, context: Context, pos: Position = NoPosition): SearchResult = + inferImplicit(EmptyTree, pt, reportAmbiguous = true, isView = false, context, saveAmbiguousDivergent = true, pos) + + def inferImplicitByTypeSilent(pt: Type, context: Context, pos: Position = NoPosition): SearchResult = + inferImplicit(EmptyTree, pt, reportAmbiguous = false, isView = false, context, saveAmbiguousDivergent = false, pos) + + @deprecated("Unused in scalac", "2.12.0-M4") def inferImplicit(tree: Tree, pt: Type, reportAmbiguous: Boolean, isView: Boolean, context: Context): SearchResult = inferImplicit(tree, pt, reportAmbiguous, isView, context, saveAmbiguousDivergent = true, tree.pos) + @deprecated("Unused in scalac", "2.12.0-M4") def inferImplicit(tree: Tree, pt: Type, reportAmbiguous: Boolean, isView: Boolean, context: Context, saveAmbiguousDivergent: Boolean): SearchResult = inferImplicit(tree, pt, reportAmbiguous, isView, context, saveAmbiguousDivergent, tree.pos) - /** Search for an implicit value. See the comment on `result` at the end of class `ImplicitSearch` - * for more info how the search is conducted. + /** Search for an implicit value. Consider using one of the convenience methods above. This one has many boolean levers. + * + * See the comment on `result` at the end of class `ImplicitSearch` for more info how the search is conducted. + * * @param tree The tree for which the implicit needs to be inserted. * (the inference might instantiate some of the undetermined * type parameters of that tree. @@ -92,9 +111,10 @@ trait Implicits { /** A friendly wrapper over inferImplicit to be used in macro contexts and toolboxes. */ def inferImplicit(tree: Tree, pt: Type, isView: Boolean, context: Context, silent: Boolean, withMacrosDisabled: Boolean, pos: Position, onError: (Position, String) => Unit): Tree = { - val wrapper1 = if (!withMacrosDisabled) (context.withMacrosEnabled[SearchResult] _) else (context.withMacrosDisabled[SearchResult] _) - def wrapper(inference: => SearchResult) = wrapper1(inference) - val result = wrapper(inferImplicit(tree, pt, reportAmbiguous = true, isView = isView, context = context, saveAmbiguousDivergent = !silent, pos = pos)) + val result = context.withMacros(enabled = !withMacrosDisabled) { + inferImplicit(tree, pt, reportAmbiguous = true, isView = isView, context, saveAmbiguousDivergent = !silent, pos) + } + if (result.isFailure && !silent) { val err = context.reporter.firstError val errPos = err.map(_.errPos).getOrElse(pos) @@ -304,6 +324,10 @@ trait Implicits { */ object Function1 { val Sym = FunctionClass(1) + val Pre = Sym.typeConstructor.prefix + + def apply(from: Type, to: Type) = TypeRef(Pre, Sym, List(from, to)) + // It is tempting to think that this should be inspecting "tp baseType Sym" // rather than tp. See test case run/t8280 and the commit message which // accompanies it for explanation why that isn't done. @@ -1207,7 +1231,7 @@ trait Implicits { /* Re-wraps a type in a manifest before calling inferImplicit on the result */ def findManifest(tp: Type, manifestClass: Symbol = if (full) FullManifestClass else PartialManifestClass) = - inferImplicit(tree, appliedType(manifestClass, tp), reportAmbiguous = true, isView = false, context).tree + inferImplicitFor(appliedType(manifestClass, tp), tree, context).tree def findSubManifest(tp: Type) = findManifest(tp, if (full) FullManifestClass else OptManifestClass) def mot(tp0: Type, from: List[Symbol], to: List[Type]): SearchResult = { |