I find the posts on this blogs too much Ocaml biased. Ok, haskell has
not modules and it is somewhat missing, but using TypeFamilies, you can
emulate modules (and even 1st order modules which are available in Ocaml
only since 3.11 or 3.12), and in the other hand there is still not yet
any convenient way to have type classes in Ocaml. And it is not very
often that I would like to implement a module where a simple type class
wouldn't fit.

Are type classes planned in the future (and if not, what are the
reasons not to have it)?.