specifying and solving module dependencies

related: http://www.mancoosi.org/papers/ (not for Haskell modules, but for Debian-like package specs) PS: keep in mind that even the most elaborated versioned dependency mechanism is just a work-around - as long as we don't have *all* software properties in the types. Only then could we have a formal proof that a module A can use module B2 instead of module B1, etc. And, we do not "just" want correctness w.r.t. a specification, but also resource consumption. - J.W.