> routing and parameters are relying on magic # annotations

Actually, as someone almost finished with the book, that brings up an interesting point. What controls # annotations and how do you hook into them (which also answers the question of how magic they are)?

If it's fairly standard and obvious how to look up, I think I might not classify them as much "magic", but truthfully, I have no idea at all. Maybe I'm just not remembering that part of the book (I did take a break for a month), or maybe I didn't make a connection that was implied?