[Haskell-cafe] From monads to monoids in a small category

Alberto G. Corona agocorona at gmail.com
Tue Sep 4 12:39:20 CEST 2012

"Monads are monoids in the category of endofunctors"

This Monoid instance for the endofunctors of the set of all  elements
of (m a)   typematch in Haskell with FlexibleInstances:

instance Monad m => Monoid  (a -> m a) where
   mappend = (>=>)   -- kleisly operator
   mempty  = return

The article can be found here:


I would appreciate some comments.

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