compilation - Scala double definition (2 methods have the same type erasure)

Question

I wrote this in scala and it won't compile:

class TestDoubleDef{
  def foo(p:List[String]) = {}
  def foo(p:List[Int]) = {}
}

the compiler notify:

[error] double definition:
[error] method foo:(List[String])Unit and
[error] method foo:(List[Int])Unit at line 120
[error] have same type after erasure: (List)Unit

I know JVM has no native support for generics so I understand this error.

I could write wrappers for List[String] and List[Int] but I'm lazy :)

I'm doubtful but, is there another way expressing List[String] is not the same type than List[Int]?

Thanks.

Answer 1

Instead of inventing dummy implicit values, you can use the DummyImplicit defined in Predef which seems to be made exactly for that:

class TestMultipleDef {
  def foo(p:List[String]) = ()
  def foo(p:List[Int])(implicit d: DummyImplicit) = ()
  def foo(p:List[java.util.Date])(implicit d1: DummyImplicit, d2: DummyImplicit) = ()
}