ADD_ACKNOWLEDGER (Phrasing_slur_engraver, slur);
ADD_ACKNOWLEDGER (Phrasing_slur_engraver, text_script);
ADD_ACKNOWLEDGER (Phrasing_slur_engraver, tie);
ADD_ACKNOWLEDGER (Phrasing_slur_engraver, slur);
ADD_ACKNOWLEDGER (Phrasing_slur_engraver, text_script);
ADD_ACKNOWLEDGER (Phrasing_slur_engraver, tie);