Yield right-to-left instances of klass in expr.
abjad> staff = Staff(FixedDurationTuplet((2, 8), construct.run(3)) * 2)
abjad> pitchtools.diatonicize(staff)
abjad> print staff.format
\new Staff {
\times 2/3 {
c'8
d'8
e'8
}
\times 2/3 {
f'8
g'8
a'8
}
}
abjad> for x in iterate.backwards(staff, Note):
... x
...
Note(a', 8)
Note(g', 8)
Note(f', 8)
Note(e', 8)
Note(d', 8)
Note(c', 8)
abjad> for x in iterate.backwards(staff, FixedDurationTuplet):
... x
...
FixedDurationTuplet(1/4, [f'8, g'8, a'8])
FixedDurationTuplet(1/4, [c'8, d'8, e'8])
Note
This naive iteration ignores threads.