Tag Archives: free

Parametricity for Bifunctor

I’ve begun work to add Bifunctor, Bifoldable, and Bitraversable to the Typeclassopedia. While thinking and writing about Bifunctor I ended up proving some “folklore” results for my own satisfaction, and decided someone might possibly find it useful if I formally … Continue reading

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foldr is made of monoids

> import Data.Monoid In his recent blog post What is foldr made of?, Tom Ellis made the clever observation that foldr is equivalent in power to the combination of map and compose, where > compose :: [a -> a] -> … Continue reading

Posted in haskell, math | Tagged , , , , | 15 Comments