- Stream_event *ev = events_[START];
-
- bool double_slurs = to_boolean (get_property ("doubleSlurs"));
-
- Grob *slur = make_spanner ("Slur", events_[START]->self_scm ());
- Direction updown = to_dir (ev->get_property ("direction"));
- if (updown && !double_slurs)
- set_grob_direction (slur, updown);
-
- slurs_.push_back (slur);
-
- if (double_slurs)
- {
- set_grob_direction (slur, DOWN);
- slur = make_spanner ("Slur", events_[START]->self_scm ());
- set_grob_direction (slur, UP);
- slurs_.push_back (slur);
- }
+ Stream_event *ev = start_events_[i];
+ string id = robust_scm2string (ev->get_property ("spanner-id"), "");
+ bool have_slur = false;
+ // Check if we already have a slur with the same spanner-id.
+ // In that case, don't create a new slur, but print a warning
+ for (vsize j = 0; j < slurs_.size (); j++)
+ have_slur = have_slur || (id == robust_scm2string (slurs_[j]->get_property ("spanner-id"), ""));
+
+ if (have_slur)
+ {
+ // We already have a slur, so give a warning and completely ignore
+ // the new slur.
+ ev->origin ()->warning(_ ("already have slur"));
+ start_events_.erase (start_events_.begin () + i);
+ }
+ else
+ {
+ Grob *slur = make_spanner ("Slur", ev->self_scm ());
+ Direction updown = to_dir (ev->get_property ("direction"));
+ slur->set_property ("spanner-id", ly_string2scm (id));
+ if (updown)
+ set_grob_direction (slur, updown);
+ slurs_.push_back (slur);
+
+ if (to_boolean (get_property ("doubleSlurs")))
+ {
+ set_grob_direction (slur, DOWN);
+ slur = make_spanner ("Slur", ev->self_scm ());
+ slur->set_property ("spanner-id", ly_string2scm (id));
+ set_grob_direction (slur, UP);
+ slurs_.push_back (slur);
+ }
+ }