The alternative to newtypes is probably to go the same route as OCaml and have people explicitly bring their own instances for typeclasses, instead of allowing each type only one instance?
I think OCaml calls these things modules or so. But the concepts are similar. For most cases, when there's one obvious instance that you want, having Haskell pick the instance is less of a hassle.
I think OCaml calls these things modules or so. But the concepts are similar. For most cases, when there's one obvious instance that you want, having Haskell pick the instance is less of a hassle.