New in version 2.3.
True when expr is component with LilyPond command mark attached:
abjad> note = Note("c'4")
abjad> marktools.StemTremolo(16)(note)
StemTremolo(16)(c'4)
abjad> marktools.is_component_with_stem_tremolo_attached(note)
True
False otherwise:
abjad> note = Note("c'4")
abjad> marktools.is_component_with_stem_tremolo_attached(note)
False
Return boolean.