MonadPlus instance for ContT

John Wiegley johnw at
Mon Jun 24 21:54:50 CEST 2013

>>>>> Edward Kmett <ekmett at> writes:

> Because there are many monads for which you do not want this construction!
> It isn't what you mean when you use mappend on [a] for sure! It is also
> different from the behavior for Monad, and it rules out those and many many
> other perfectly valid uses by overlap.

Thanks for the clarification, Edward!  Very good points.

John Wiegley
FP Complete                         Haskell tools, training and consulting               johnw on #haskell/

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