Re: Proposal: Add isLeft/isRight to Data.Either

Hi Herbert, On Tue, Dec 04, 2012 at 11:02:07PM +0100, Herbert Valerio Riedel wrote:

btw, what I've been missing even more than isLeft/isRight is something like

leftMaybe :: Either a b -> Maybe a leftMaybe (Left x) = Just x leftMaybe _ = Nothing

rightMaybe :: Either a b -> Maybe b rightMaybe (Right x) = Just x rightMaybe _ = Nothing

There seems to be support for this. I think it would be useful to have a separate proposal/patch. Cheers, Simon