Performance.CtxMusical context.
The context is the context in which music is interpreted.
val v :
?init:'a t ->
?time_s:time_s ->
?wn_dur_s:dur_s ->
?instrument:Instrument.t ->
?player:'a player ->
?transp:Pitch.rel ->
?volume:volume ->
unit ->
'a tv ~init () is a context with values from init (defaults to default) except for those overriden explictely.
val instrument : 'a t -> Instrument.tinstrument c is the instrument performing in c.