Proposal: Add isLeft/isRight to Data.Either

[Bas van Dijk]

On 7 December 2012 10:25, Erik Hesselink <hesselink at gmail.com> wrote:
> On Fri, Dec 7, 2012 at 9:29 AM, Bas van Dijk <v.dijk.bas at gmail.com> wrote:
>> On 6 December 2012 23:05, Evan Laforge <qdunkan at gmail.com> wrote:
>>>>>   - 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