New in version 2.6.
True when expr is a sequence of named chromatic pitch tokens:
abjad> named_chromatic_pitch_tokens = [('c', 4), pitchtools.NamedChromaticPitch("a'")]
abjad> pitchtools.all_are_named_chromatic_pitch_tokens(named_chromatic_pitch_tokens)
True
True when expr is an empty sequence:
abjad> pitchtools.all_are_named_chromatic_pitch_tokens([])
True
Otherwise false:
abjad> pitchtools.all_are_named_chromatic_pitch_tokens('foo')
False
Return boolean.