apfelmus wrote:
Yes, bring 'em in! But _only_ under their standard name :)
class Category c where id :: c a a (.) :: c b c -> c a b -> c a c
class Category cat where id :: cat a a (.) :: cat b c -> cat a b -> cat a c I'm not against this, but it would mean moving Category to the Prelude. As far as bikeshed issues: 1. I don't care either way about the name. "Category" or "Morphism" would both be fine. 2. I made a sort of "minimal bikeshed" patch, with this from Arrow: (>>>) :: comp a b -> comp b c -> comp a c But I actually prefer (<<<) :: comp b c -> comp a b -> comp a c , like (.). I originally called that member 'compose'.
Unfortunately, the names id and (.) are already taken / give headache to those that don't like map :: Functor f => (a -> b) -> f a -> f b .
I prefer the generalised 'map' too. In fact I always use fmap over lists, map is just one more thing to remember so I don't. But that's another proposal... -- Ashley Yakeley Seattle, WA