I ran into a similar problem teaching myself perl a couple years ago by doing a short tutorial then foolishly jumping into a co-worker's code. "What the hell is '$.'? Hmm, well I'm sure Google can help me. What? No matching documents?!? What is this crazy s.o.b. doing here??"
Glad to hear I'm not the only one who's had trouble with this. I remember reading some C code once and I saw some strange operators I had never seen before... <? and >?, if I remember correctly.
I eventually figured out they were GCC extensions for "min" and "max", but only after a painful experience trying to get more info out of Google than "here's how you do addition and multiplication in C!"