I've found that extra info to be interesting and useful, it's true, when I can get it. For instance, Norvig's Lisp-in-Python essays came out with the code still

I've found that extra info to be interesting and useful, it's true, when I can get it. For instance, Norvig's Lisp-in-Python essays came out with the code still in some flux and I could compare his improvements to mine.