New in version 1.1.
List badly formed components in expr:
abjad> staff = Staff("c'8 d'8 e'8 f'8")
abjad> staff[1].written_duration = Duration(1, 4)
abjad> spannertools.BeamSpanner(staff[:])
BeamSpanner(c'8, d'4, e'8, f'8)
abjad> f(staff)
\new Staff {
c'8 [
d'4
e'8
f'8 ]
}
abjad> componenttools.list_badly_formed_components_in_expr(staff)
[Note("d'4")]
Beamed quarter notes are not well formed.
Return newly created list of zero or more components.