[Haskell-cafe] A function for Maybes
Brandon S. Allbery KF8NH
allbery at ece.cmu.edu
Thu Jan 25 09:22:49 EST 2007
On Jan 25, 2007, at 9:15 , John Ky wrote:
> Is there a built-in function that already does this?
> foo :: (a -> b) -> Maybe a -> Maybe b
> foo f m
> | isNothing m = Nothing
> | otherwise = Just (f (fromJust m))
Nothing specific to Maybe, because the more general liftM (over
monads) or fmap (over functors) already does it.
brandon s. allbery [linux,solaris,freebsd,perl] allbery at kf8nh.com
system administrator [openafs,heimdal,too many hats] allbery at ece.cmu.edu
electrical and computer engineering, carnegie mellon university KF8NH
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