Hacker News Reader

If you program modern Java or Kotlin map and flatMap are everywhere. I'd say the debate whether functors and monads are useful is over.

Java or Kotlin support functors or monads as design patterns, i.e. this is how a map/flatMap works with an Optional or a Stream.

The question is: if this support is enough or should the type system be enhanced so you can abstract over/compose a functor and/or a monad ?

The answer to this question is IMO still open.