[gpm]

No, I don't think so, not unless there's some feature of Haskell type classes I'm completely unaware of.

If anything it's closer to SFINAE in C++ where it tries to implement methods but then doesn't consider it an error if it fails. Then infers type-classes based on the outcome of the SFINAE process. Or the macro analogy another poster made isn't bad (with the caveat that it's a type system aware macro - which at least in rust is strange).