majalan

Copperbox revision 3041.

I've added cursor position to the EventList representation via a State monad. This should be better for "symbolic concatenation" than using the bounding box-like time span. Time span would suffer from the staccato / legato problem that I recently solved in PhraseMonad: concatenation that makes musical sense wants to be based on symbolic note lengths (so the music stays in time) rather than actually note lengths which may be shorter (staccato) or longer (sostenuto / legato) than their "beat".

Intriguingly, having cursor position in the representation might open the possibility of improving the API for behaviors over time.