+Music::get_length () const
+{
+ SCM lst = get_property ("length");
+ if (unsmob_moment (lst))
+ return *unsmob_moment (lst);
+
+ if (ly_is_procedure (length_callback_))
+ {
+ SCM res = scm_call_1 (length_callback_, self_scm ());
+ return *unsmob_moment (res);
+ }
+
+ return Moment (0);
+}
+
+Moment
+Music::start_mom () const
+{
+ SCM lst = start_callback_;
+ if (ly_is_procedure (lst))
+ {
+ SCM res = scm_call_1 (lst, self_scm ());
+ return *unsmob_moment (res);
+ }
+
+ Moment m;
+ return m;
+}
+
+void
+print_alist (SCM a, SCM port)
+{
+ /* SCM_EOL -> catch malformed lists. */
+ for (SCM s = a; scm_is_pair (s); s = scm_cdr (s))
+ {
+ scm_display (scm_caar (s), port);
+ scm_puts (" = ", port);
+ scm_write (scm_cdar (s), port);
+ scm_puts ("\n", port);
+ }
+}
+
+
+Pitch
+Music::generic_to_relative_octave (Pitch last)
+{
+ SCM elt = get_property ("element");
+ Pitch *old_pit = unsmob_pitch (get_property ("pitch"));
+ if (old_pit)
+ {
+ Pitch new_pit = *old_pit;
+ new_pit = new_pit.to_relative_octave (last);
+
+ SCM check = get_property ("absolute-octave");
+ if (scm_is_number (check)
+ && new_pit.get_octave () != scm_to_int (check))
+ {
+ Pitch expected_pit (scm_to_int (check),
+ new_pit.get_notename (),
+ new_pit.get_alteration ());
+ origin ()->warning (_f ("octave check failed; expected \"%s\", found: \"%s\"",
+ expected_pit.to_string (),
+ new_pit.to_string ()));
+ new_pit = expected_pit;
+ }
+
+ set_property ("pitch", new_pit.smobbed_copy ());
+
+ last = new_pit;
+ }
+
+ if (Music *m = unsmob_music (elt))
+ last = m->to_relative_octave (last);
+
+ last = music_list_to_relative (get_property ("elements"), last, false);
+ return last;
+}
+
+Pitch
+Music::to_relative_octave (Pitch last)
+{
+ SCM callback = get_property ("to-relative-callback");
+ if (ly_is_procedure (callback))
+ {
+ Pitch *p = unsmob_pitch (scm_call_2 (callback, self_scm (), last.smobbed_copy ()));
+ return *p;
+ }
+
+ return generic_to_relative_octave (last);
+}
+
+void
+Music::compress (Moment factor)