gistfile1.txt

scala> def foo[A[_]] = 1
foo: [A[_]]=> Int

scala> foo[List]
res11: Int = 1

scala> foo[Int]
<console>:24: error: Int takes no type parameters, expected: one
              foo[Int]
                  ^

scala> foo[Any]
res13: Int = 1

scala> foo[Nothing]
res14: Int = 1

scala> wat