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gergoerdi/gist:5324462

Created April 6, 2013 02:33
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Trying to observe a difference between `pure id <*> x` and `x`
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gistfile1.hs
import Control.Applicative.Free
import Control.Applicative
import Control.Monad.Identity
import Data.Monoid
count :: (Functor eff) => Free eff a -> Int
count = getSum . runIdentity . analyze (const $ Identity $ Sum 1)
test :: (Functor eff) => Free eff a -> (Int, Int)
test x = (count $ pure id <*> x, count x)
test' :: (Int, Int)
test' = test (effect undefined :: Free Identity ())
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