Sure:
newtype IOMayfail a = IOMayfail {runIOMayfail :: MaybeT IO a}instance Monad IOMayfail where return = IOMayfail . return IOMayfail m >>= f = IOMayfail $ m >>= runIOMayfail . f fail = whatever you like Matthias Görgens wrote on 25.06.2009 17:28:
Thanks. Can I add something like fail?
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