Recovering From Functional Programming

James Hague has an interesting series of posts about functional programming, the latest of which, “Functional Programming Doesn’t Work (and what to do about it)” starts with:

Read suddenly and in isolation, this may be easy to misinterpret, so I suggest first reading some past articles which have led to this point.

I agree with his thesis: eliminating mutable state, side effects, and/or global variables doesn’t always make programs cleaner. I’ll know that we have a working theory of program complexity (as opposed to algorithmic complexity) when such recommendations can be prescriptive.