Functional languages: What they are, where they're going

Even as some argue exactly what it is, functional programming keeps attracting developers. And three of the most popular functional languages -- Clojure, F#, and Scala -- are on tap for improvements.
Functional programming has a core appeal for some developers, says Scala founder Martin Odersky: "The programmers in that segment like functional programming because it makes code clearer, better structured, and it prevents many classes of errors." But some argue that functional programming le