Re: rfc: include bimap into Data.Either

On 2014-04-18 at 22:54:18 +0200, Tobias Florek wrote:

i propose to include the following functions into Data.Either.

mapLeft :: (a->b) -> Either a c -> Either b c mapLeft f = bimap f id

bimap :: (a -> b) -> (c -> d) -> Either a c -> Either b d bimap f g = either (Left . f) (Right . g)

as these are just specialized versions of existing functions, i.e. mapLeft = Control.Arrow.left bimap = Control.Arrow.(+++) I'm not convinced we should add these