Compiler cannot unify types of a GADT (2/2)

[regiskuckaertz]

Compiler version

3.0.0-RC3

Minimized code

enum Func[-A, +B] {
  case Double extends Func[Int, Int]
  case ToString extends Func[Float, String]
}

def runFunc[A, B](func: Func[A, B], input: A): B =
  (func, input) match {
    case (Func.Double, i) => i * 2
    case (Func.ToString, f) => f.toString
  }

Output

Expectation

The compiler should be able to unify input and output types depending on the case being evaluated.

[LPTK]

Duplicate of #12390