diff options
| -rw-r--r-- | src/compiler/scala/tools/nsc/typechecker/Macros.scala | 44 |
1 files changed, 17 insertions, 27 deletions
diff --git a/src/compiler/scala/tools/nsc/typechecker/Macros.scala b/src/compiler/scala/tools/nsc/typechecker/Macros.scala index 7c5d458fee..57180e66d5 100644 --- a/src/compiler/scala/tools/nsc/typechecker/Macros.scala +++ b/src/compiler/scala/tools/nsc/typechecker/Macros.scala @@ -144,32 +144,22 @@ trait Macros extends scala.tools.reflect.FastTrack with Traces { macroTraceVerbose("macroImplSigs are: ")(paramsss, implRetTpe) } - private def transformTypeTagEvidenceParams(paramss: List[List[Symbol]], transform: (Symbol, Symbol) => Option[Symbol]): List[List[Symbol]] = { - if (paramss.length == 0) + private def transformTypeTagEvidenceParams(paramss: List[List[Symbol]], transform: (Symbol, Symbol) => Symbol): List[List[Symbol]] = { + import definitions.{ AbsTypeTagClass, MacroContextClass } + if (paramss.isEmpty || paramss.last.isEmpty) return paramss - val wannabe = if (paramss.head.length == 1) paramss.head.head else NoSymbol - val contextParam = if (wannabe != NoSymbol && wannabe.tpe <:< definitions.MacroContextClass.tpe) wannabe else NoSymbol - - val lastParamList0 = paramss.lastOption getOrElse Nil - val lastParamList = lastParamList0 flatMap (param => param.tpe match { - case TypeRef(SingleType(NoPrefix, contextParam), sym, List(tparam)) => - var wannabe = sym - while (wannabe.isAliasType) wannabe = wannabe.info.typeSymbol - if (wannabe != definitions.AbsTypeTagClass) - List(param) - else - transform(param, tparam.typeSymbol) map (_ :: Nil) getOrElse Nil - case _ => - List(param) - }) - - var result = paramss.dropRight(1) :+ lastParamList - if (lastParamList0.isEmpty ^ lastParamList.isEmpty) { - result = result dropRight 1 + val ContextParam = paramss.head match { + case p :: Nil => p filter (_.tpe <:< definitions.MacroContextClass.tpe) + case _ => NoSymbol } - - result + def isTag(sym: Symbol): Boolean = (sym == AbsTypeTagClass) || (sym.isAliasType && isTag(sym.info.typeSymbol)) + def transformTag(param: Symbol): Symbol = param.tpe match { + case TypeRef(SingleType(NoPrefix, ContextParam), sym, tp :: Nil) if isTag(sym) => transform(param, tp.typeSymbol) + case _ => param + } + val last = paramss.last map transformTag filterNot (_ eq NoSymbol) + if (last.isEmpty) paramss.init else paramss.init :+ last } /** As specified above, body of a macro definition must reference its implementation. @@ -429,7 +419,7 @@ trait Macros extends scala.tools.reflect.FastTrack with Traces { } var actparamss = macroImpl.paramss - actparamss = transformTypeTagEvidenceParams(actparamss, (param, tparam) => None) + actparamss = transformTypeTagEvidenceParams(actparamss, (param, tparam) => NoSymbol) val rettpe = if (!ddef.tpt.isEmpty) typer.typedType(ddef.tpt).tpe else computeMacroDefTypeFromMacroImpl(ddef, macroDef, macroImpl) val (reqparamsss0, reqres0) = macroImplSigs(macroDef, ddef.tparams, ddef.vparamss, rettpe) @@ -550,7 +540,7 @@ trait Macros extends scala.tools.reflect.FastTrack with Traces { // val defParamss = macroDef.paramss val defParamss = mmap(macroDdef.vparamss)(_.symbol) var implParamss = macroImpl.paramss - implParamss = transformTypeTagEvidenceParams(implParamss, (param, tparam) => None) + implParamss = transformTypeTagEvidenceParams(implParamss, (param, tparam) => NoSymbol) val implCtxParam = if (implParamss.length > 0 && implParamss(0).length > 0) implParamss(0)(0) else null def implParamToDefParam(implParam: Symbol): Symbol = { @@ -799,7 +789,7 @@ trait Macros extends scala.tools.reflect.FastTrack with Traces { // empty-paramlist def + nullary invocation => uh-oh, we need to append a List() to argss // empty-paramlist def + empty-arglist invocation => paramss and argss match, everything is okay // that's almost it, but we need to account for the fact that paramss might have context bounds that mask the empty last paramlist - val paramss_without_evidences = transformTypeTagEvidenceParams(paramss, (param, tparam) => None) + val paramss_without_evidences = transformTypeTagEvidenceParams(paramss, (param, tparam) => NoSymbol) val isEmptyParamlistDef = paramss_without_evidences.nonEmpty && paramss_without_evidences.last.isEmpty val isEmptyArglistInvocation = argss.nonEmpty && argss.last.isEmpty if (isEmptyParamlistDef && !isEmptyArglistInvocation) { @@ -856,7 +846,7 @@ trait Macros extends scala.tools.reflect.FastTrack with Traces { case _ => throw new Error("unsupported tpe: " + tpe) } - Some(tparam) + tparam }) val tags = paramss.last takeWhile (_.isType) map (resolved(_)) map (tpe => if (tpe.isConcrete) context.TypeTag(tpe) else context.AbsTypeTag(tpe)) if (paramss.lastOption map (params => !params.isEmpty && params.forall(_.isType)) getOrElse false) argss = argss :+ Nil |