[EdwardDiego]

I guess in Java, it'd look something like this:

  public class JavaOption<T> {
    
    public <U> JavaOption<U> map(Function<T, U> func) {
        //todo
    }
  }

Kotlin might be a closer match in semantics if I use an extension function:

  fun <T, U> Optional<T>.map(func: (T) -> U): Optional<U>  {
      // todo
  }