Brandon.Si(mmons)

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The Total Recall Combinator

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infixr 9 .:
(.:) :: (b -> c) -> (a -> a1 -> b) -> a -> a1 -> c
(.:) = (.)(.)(.)

This can be used to compose a string of functions with a binary function stuck on the end. For example:

Usage example
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lookupPlusOne :: (Ord k, Monad m, Num n) => k -> Map k n -> m n
lookupPlusOne = liftM (+1) .: lookup

(picked up from some folks on #haskell)

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