darcs patch: Add equating p x y = p x == p y

[Malcolm Wallace]

Jon Fairbairn <jon.fairbairn at cl.cam.ac.uk> wrote:

> Control.Combinators? Such general beasts as mapFst, mapSnd
> and >< from Data.Graph.Inductive.Query.Monad could go in
> there, as could other pair handling combinators like
> (f <&> g) x = (f x, g x)

Pairs are a data structure. I would be inclined to place mapFst, mapSnd,
curry, and uncurry in a separate module, probably Data.Pair or
Data.Tuple.

Regards,
    Malcolm