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

On 7 December 2012 10:25, Erik Hesselink wrote:

On Fri, Dec 7, 2012 at 9:29 AM, Bas van Dijk wrote:

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On 6 December 2012 23:05, Evan Laforge wrote:

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- I often use the 'when'-like combinator 'whenJust' in monadic code:

whenJust :: Monad m => Maybe a -> (a -> m ()) -> m () whenJust (Just x) a = a x whenJust _ _ = return ()

+1. whenJust is defined also in Agda.Utils.Monad, should also added to Control.Monad.

Off topic, but I have whenJust in my local library too, and I use it all the time.

In a project at work:

$ grep -r whenJust --include=\*.hs . | wc -l 27

There is no need to define whenJust, since it is just a specialization of forM_ from Data.Foldable.

Thanks for pointing this out! Replacing the 27 whenJusts as we speak... Bas