18 Jan
2016
18 Jan
'16
3:32 p.m.
On Mon, 18 Jan 2016, David Feuer wrote:
I'd be strongly +1 on that too! Traversable is strong magic.
I am opposed to all these Functor, Foldable, Traversable stuff on tuples (including pairs). Why should the last element of a tuple get a special treatment? I suspect that if you use such instances you are making something dirty. I am afraid that those instance may hide type errors or make type errors incomprehensible. E.g. if you get a stack of fmap's wrong, you do not get a "no instance for Functor ((,) a)" but instead the type mismatch occurs at a different level. I would never use such an instance. Can I be warned if I accidentally use it anyway?