[Haskell-cafe] ANNOUNCE: control-monad-failure and safe-failure
nicolas.pouillard at gmail.com
Tue Nov 17 07:18:07 EST 2009
Excerpts from Kalman Noel's message of Tue Nov 17 12:55:54 +0100 2009:
> Nicolas Pouillard schrieb:
> >>>> class MonadFailure e m where failure :: e -> m a
> >> Why is it called "MonadFailure" (specifically, what's the "Monad" bit doing
> >> there)?
> > Because of 'Monad m' being a superclass of 'MonadFailure e m'.
> > Here is the class:
> > class Monad m => MonadFailure e m where
> > failure :: e -> m a
> Oh ok; I misguidedly took the line at the top to be the class definition. I'd
> still be interested if such a simple Failure class could be meaningful or
> useful for mere, say, Applicatives.
I think it is meaningful.
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