// This test case was extracted from `names-defaults-neg.scala` // It pinpoints an improvement an error message that results from // a type inference failure object Test extends App { test4(test4$default$1) def test4[T[P]](x: T[T[List[T[X forSome { type X }]]]]) = ??? def test4$default$1[T[P]]: List[Int] = ??? } /* OLD: no type parameters for method test4: (x: T[T[List[T[X forSome { type X }]]]])Nothing exist so that it can be applied to arguments (List[Int]) --- because --- argument expression's type is not compatible with formal parameter type; found : List[Int] required: ?T test4(test4$default$1) ^ NEW: no type parameters for method test4: (x: T[T[List[T[X forSome { type X }]]]])Nothing exist so that it can be applied to arguments (List[Int]) --- because --- argument expression's type is not compatible with formal parameter type; found : List[Int] required: ?T[?T[List[?T[X forSome { type X }]]] test4(test4$default$1) */