# Talk:MapReduce as a monad

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## Revision as of 21:16, 2 April 2011

## Monads

Why is it mapreduce as a *monad*? Map just requires Functor, and reduce sounds like `mappend`, so it'd just be MapReduce as a monoid. --Gwern 20:31, 2 April 2011 (UTC)

Because the key point is that both Map and Reduce can be seen as monadic functions, and so then MapReduce is just a matter of repeated bind operations. Think of it as a generalised State monad. julianporter 21:16, 2 April 2011 (UTC)