Nah, the type system is perfectly fine in this case: "Given (Just someValue), return someValue". Exactly what happened here, the precondition just was not fulfilled and I left the case dealing the unfulfilled precondition undefined. If one cares about such things, one should simply use one of the numerous alternative Preludes out there (to make sure to actually never use fromMaybe, head and the 3 other functions that nobodoy uses form the standard Prelude) and turn the warnings for incomplete pattern matches on. At least, thats how you could deal with it in real life.
If it is not practical matters that are the concern here, there are more than enough languages that only allow total functions and offer other sweet stuff. Haskell's main purpose was to be a lazy-by-default-language, and that people can actually write practical stuff in it is a nice side-effect.
