There is subtyping.

A more practical (though not necessarily realistic) example might be:

  sealed interface List<T> permits Cons<T>, None<T> {
    record Cons<T>(T head, List<T> tail) {}
    record None<T>() {}
  }


  // some function only wanting the  first elem of a list
  switch (List<T> list) {
    case Cons<>(T head, var tail) -> // do something
    default -> {}
  }

If you have used Haskell or similarly strongly typed FP language, you can see how great pattern matching can be.