[Haskell-cafe] [Haskell] Functor => Applicative => Monad

Tillmann Rendel rendel at informatik.uni-marburg.de
Wed Dec 15 10:55:54 CET 2010

John Smith proposed:
> a failed pattern match should error in the same way as is does for
> pure code, while in MonadPlus, the current behaviour could be
> maintained with mzero

Lennart Augustsson wrote:
> Any refutable pattern match in do would force MonadFail (or MonadPlus
> if you prefer).

I guess that would work out, but I think John proposed something else.


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