Hello, In keeping with my small but seemingly extremely controversial suggestions for changes to the Prelude, here's a suggestion which I think is elegant and worth considering for the Haskell' Prelude: Rename fmap to map (like it was in Haskell 1.4), and define (.) as a synonym for it. Additionally, add the instance: instance Functor ((->) e) where map f g x = f (g x) (and hopefully the corresponding Monad instance as well) This has the beautiful effect of unifying the notation for two of the most important things in functional programming: function composition and functorial application, and will hopefully reduce the number of extraneous functor application definitions in the Prelude and libraries. Note that the fusion law for functors: map (f . g) x = map f (map g x) When written in terms of (.) becomes: (f . g) . x = f . (g . x) which means that (.) will still be reliably associative, and that the functor in question is always easily determined by the type of the last thing in any chain of (.)'s. This has a fair level of backwards compatibility obviously, as it's strictly a generalisation on both fronts. I've been playing around with it for a while, and like it quite a lot myself, though it would be more convenient to really use if it was in the Prelude. - Cale