void substitute_one_mutable_property (SCM sym, SCM val);
bool fast_substitute_grob_array (SCM sym, Grob_array *);
- virtual Interval_t<int> spanned_rank_iv ();
+ 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;