Re: Proposal: add Control.Monad.whenJust ∷ (Monad m) ⇒ Maybe α→(α→ m ()) → m ()

1 Dec 2011


      On 11/30/2011 11:51 PM, Liyang HU wrote:
...
Also, if we go down the route of whenJust, why not whenLeft and whenRight (and so on) too?
I'd rather add something like

maybeLeft ∷ Either a b → Maybe a
maybeLeft = either Just (const Nothing)

to Data.Either

Re: Proposal: add Control.Monad.whenJust ∷ (Monad m) ⇒ Maybe α→(α→ m ()) → m ()

Mikhail Vorozhtsov