diff options
| -rw-r--r-- | src/compiler/scala/tools/nsc/typechecker/Variances.scala | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/src/compiler/scala/tools/nsc/typechecker/Variances.scala b/src/compiler/scala/tools/nsc/typechecker/Variances.scala index f68f9cc140..1ba0de0192 100644 --- a/src/compiler/scala/tools/nsc/typechecker/Variances.scala +++ b/src/compiler/scala/tools/nsc/typechecker/Variances.scala @@ -71,11 +71,9 @@ trait Variances { varianceInType(pre)(tparam) case TypeRef(pre, sym, args) => if (sym == tparam) COVARIANT - else varianceInType(pre)(tparam) & { - // @PP to @AM: please give this a higher dose of correctness. - val actualArgs = if (args.isEmpty) sym.typeParams map (_.typeConstructor) else args - varianceInArgs(actualArgs, sym.typeParams)(tparam) - } + // tparam cannot occur in tp's args if tp is a type constructor (those don't have args) + else if (tp.isHigherKinded) varianceInType(pre)(tparam) + else varianceInType(pre)(tparam) & varianceInArgs(args, sym.typeParams)(tparam) case TypeBounds(lo, hi) => flip(varianceInType(lo)(tparam)) & varianceInType(hi)(tparam) case RefinedType(parents, defs) => |