Interestingly enough, the sort of error messages that you mention in OCaml occurs partly due to the inference itself. Because inference is essentially a unifica

Interestingly enough, the sort of error messages that you mention in OCaml occurs partly due to the inference itself. Because inference is essentially a unification between implicit constraints, once it finds an anomaly, the engine can't always predict correctly which among the conflicting constraints is the actual error from a user point of view. Anyway just an aside