+ // todo: move to somewhere else.
+ Real get_broken_left_end_align () const;
+ void substitute_one_mutable_property (SCM sym, SCM val);
+
+ Interval_t<Moment> spanned_time () const;
+ virtual Interval_t<int> spanned_rank_interval () const;
+ void set_bound (Direction d, Grob *);
+ Item *get_bound (Direction d) const;
+