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tel/CPS.hs

Created January 1, 2015 00:53
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CPS causes function composition to flip directions
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CPS.hs
{-# LANGUAGE RankNTypes #-}
{-# LANGUAGE TypeOperators #-}
type b <~ a = forall c . (b -> c) -> a -> c
back :: (a -> b) -> (b <~ a)
back f = (. f)
fwd :: (b <~ a) -> (a -> b)
fwd g = g id
(>>>) :: (a -> b) -> (b -> c) -> (a -> c)
f >>> g = fwd (back f . back g)
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