4 Staff margins are also markings attached to barlines. They should be
5 left of the staff, and be centered vertically with respect to the staff.
6 They may be on normal staves, but also on compound staves, like the
21 \context PianoStaff
<<
23 \set PianoStaff
.instrumentName
= "Piano"
24 \set Staff
.instrumentName
= "Right" { c''4 }}
26 \set Staff
.instrumentName
= "Left"
32 \set vocalName
= "bert"