ADD_ACKNOWLEDGER (Figured_bass_position_engraver, bass_figure_alignment);
ADD_END_ACKNOWLEDGER (Figured_bass_position_engraver, bass_figure_alignment);
ADD_ACKNOWLEDGER (Figured_bass_position_engraver, bass_figure_alignment);
ADD_END_ACKNOWLEDGER (Figured_bass_position_engraver, bass_figure_alignment);