diff options
Diffstat (limited to 'src/compiler/scala/reflect/macros/util/Helpers.scala')
| -rw-r--r-- | src/compiler/scala/reflect/macros/util/Helpers.scala | 32 |
1 files changed, 17 insertions, 15 deletions
diff --git a/src/compiler/scala/reflect/macros/util/Helpers.scala b/src/compiler/scala/reflect/macros/util/Helpers.scala index f12582a3a1..f40c6bb7e6 100644 --- a/src/compiler/scala/reflect/macros/util/Helpers.scala +++ b/src/compiler/scala/reflect/macros/util/Helpers.scala @@ -23,25 +23,27 @@ trait Helpers { * or to streamline creation of the list of macro arguments. */ def transformTypeTagEvidenceParams(macroImplRef: Tree, transform: (Symbol, Symbol) => Symbol): List[List[Symbol]] = { + val MacroContextUniverse = definitions.MacroContextUniverse val treeInfo.MacroImplReference(isBundle, _, macroImpl, _) = macroImplRef val paramss = macroImpl.paramss - if (paramss.isEmpty || paramss.last.isEmpty) return paramss // no implicit parameters in the signature => nothing to do - val rc = - if (isBundle) macroImpl.owner.tpe.member(nme.c) - else { - def cparam = paramss.head.head - if (paramss.head.isEmpty || !(cparam.tpe <:< MacroContextClass.tpe)) return paramss // no context parameter in the signature => nothing to do - cparam - } + val ContextParam = paramss match { + case Nil | _ :+ Nil => NoSymbol // no implicit parameters in the signature => nothing to do + case _ if isBundle => macroImpl.owner.tpe member nme.c + case (cparam :: _) :: _ if cparam.tpe <:< MacroContextClass.tpe => cparam + case _ => NoSymbol // no context parameter in the signature => nothing to do + } def transformTag(param: Symbol): Symbol = param.tpe.dealias match { - case TypeRef(SingleType(SingleType(_, ac), universe), WeakTypeTagClass, targ :: Nil) - if ac == rc && universe == MacroContextUniverse => - transform(param, targ.typeSymbol) - case _ => - param + case TypeRef(SingleType(SingleType(_, ContextParam), MacroContextUniverse), WeakTypeTagClass, targ :: Nil) => transform(param, targ.typeSymbol) + case _ => param + } + ContextParam match { + case NoSymbol => paramss + case _ => + paramss.last map transformTag filter (_.exists) match { + case Nil => paramss.init + case transformed => paramss.init :+ transformed + } } - val transformed = paramss.last map transformTag filter (_ ne NoSymbol) - if (transformed.isEmpty) paramss.init else paramss.init :+ transformed } /** Increases metalevel of the type, i.e. transforms: |