Comment by nimih

In Haskell specifically, arrays really do allow for the more general definition. This makes the library documentation[1] quite a bit more intimidating to newcomers (speaking from personal experience), but saves you the boilerplate and hassle of figuring out the mapping yourself if you're indexing your array by some weird nonsense like `[(False, 'a', 5000, 0)..(True, 'z', 9001, 4)] :: (Bool, Char, Integer, Int8)`.

[1] https://hackage.haskell.org/package/array-0.5.8.0/docs/Data-...