While Haskell language is definitely invented (and maybe you have not yet discovered it's documentation's sacred secrets), natural numbers, logics, category theory, which were selected for it's concepts are as definitely discovered. And very likely (if there are any aliens), their concepts are... isomorphic to those, while C++ as we know it most definitely has been reinvented only in a couple of thousand parallel universes, which already collapsed to a lower-dimensional branes.