I was debating whether on not to put that last sentence because I knew that it would lead to a technical discussion that was aside from the meaning of the question. My question is more -- why choose an `IO ()` as an example of something being called for its value (especially since the article isn't aimed at a Haskell audience)
Yeah, that's probably not a wise decision on part of the author. The IO monad is nifty but of minor importance in the grand scheme of things, and distracts when making a mostly language independent point.
