I'm a armchair programming-language theorist, and I know … quite a few programming languages, some to extensive depths. (Hell, I've built more than my fair share.)
Most of the information I've found for learning Mathematica seems to focus (rightfully-so) on non-programming (or beginner-level programming) mathematicians, or is reference-style (assuming you already know the basics.)
I'm sure I can puzzle this out from trial-and-error (I've already got something of an intuition for what I'm going to find, thanks to seeing the phrase ‘a Lisp with some cool pattern-matching’), but I'm curious what the best resources out there are for thoroughly learning the Wolfram language (evaluation model, inspirations, etceteras.)