Hi guys, is there some library with a Monad (+Applicative, Functor...) instance of the following type: data Todo a b = Todo [a] | Done b Thanks! Corentin -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mail.haskell.org/pipermail/haskell-cafe/attachments/20160816/87e97f45/attachment.html>