zmidi-basic

Copperbox revision 2423.

I've put rests back into the syntax and added a toy module experimenting with beat pattern construction. Unfortunately, the real work work has largely run into the sand - I've actually coded very similar beat pattern construction before but never found it pleasant to program with, and the objects that are nice to program with in Wumpus don't seem to have analogues for music after all.

As noted yesterday, building music isn't especially positional compared to graphics. Instead, musically objects seem more like strings that get combined and permuted then expanded (rendered) by adding more information to them - e.g. beats patterns are just strings of beat lengths that get zipped with strings of pitches to produce an output stream of notes. But this string view, whilst compact for the places where it works, often doesn't work - beat patterns can't handle triplets or half note subdivision and pitch sets can't handle accidental pitch changes outside the tones of the current scale. So I'm stuck at the same place that I was with Neume and Bala when I decided to punt them into the long grass and work on Wumpus.