[eduction]

There's a spectrum of FP languages with Haskell near the "pure" end where it truly becomes a pain to do things like io and Clojure at the more pragmatic end where not only is it accepted that you'll need to do non functional things but specific facilities are provided to help you do them well and in a way that can be readily brought into the functional parts of the language.

(I'm biased though as I am immersed in Clojure and have never coded in Haskell. But the creator of Clojure has gone out of his way to praise Haskell a bunch and openly admits where he looked at or borrowed ideas from it.)