Unimplemented stub in Elm

Question

Does Elm have an expression that produces bottom/diverges, like Haskell's error or Rust's unimplemented!()?

e.g.

map : (a -> b) -> List a -> List b
map = unimplemented

Answer 1

Yes, Debug.crash has the type String -> a which you can use like this:

map : (a -> b) -> List a -> List b
map = Debug.crash "unimplemented"