MT

Copperbox revision 827.

I've reached a dead end with the current incarnation of Bala. The current examples do an adequate job of generating LilyPond, but they are poor models of music - the LilyPond output is shorter, more concise than the program code to generate it. So I'm going to work on something else - MT. I don't plan to make MT into a usable library, but keep it as a set of sketches translating some pieces of (mathematical) music theory into code. The first sketches are modules implementing the T/I (translation - inversion) and PLR groups.