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reinh/gist:3783635

Created September 25, 2012 18:42
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gistfile1.hs
import Control.Monad
import Control.Monad.Instances
palindrome :: String -> Bool
palindrome = ap (==) reverse
palindrome "radar" --> True
@reinh
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reinh commented Sep 25, 2012

ap for the instance (-> r) (the function monad) is:

ap g f r = g r (f r)

@KirinDave
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The function monad is funny. Maybe it's just that I don't work with it too much, but I always find it sort of unpredictable compared to the other monads. Contrast this to, say, the Arrow definition for functions which almost always seems to make code clearer.

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