My point is that it's not "(typeclasses, interfaces, whatever)". They're similar, yes, but my point is that they aren't similar enough in the "mechanical" sense that the parent poster seems to be assuming.

EDIT: Btw, I think it may actually be possible to encode what the parent poster wants by just having a type class per method, but it's obviously a weird and non-idiomatic encoding given the presumed lack of any laws.