type Algebra f a = f a -> a newtype Mu f = InF { outF :: f (Mu f) } cata :: Functor f => Algebra f a -> Mu f -> a cata f = f . fmap (cata f) . outF
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Date: 2011-10-08 05:56 pm (UTC)type Algebra f a = f a -> a newtype Mu f = InF { outF :: f (Mu f) } cata :: Functor f => Algebra f a -> Mu f -> a cata f = f . fmap (cata f) . outF