+MAKE_SCHEME_CALLBACK(Spanner, bounds_width, 1);
+SCM
+Spanner::bounds_width (SCM grob)
+{
+ Spanner *me = unsmob_spanner (grob);
+
+
+ Grob *common = me->get_bound (LEFT)->common_refpoint (me->get_bound (RIGHT), X_AXIS);
+
+ Interval w (me->get_bound (LEFT)->relative_coordinate (common, X_AXIS),
+ me->get_bound (RIGHT)->relative_coordinate (common, X_AXIS));
+
+ w -= me->relative_coordinate (common, X_AXIS);
+
+ return ly_interval2scm (w);
+}
+