+ DECLARE_SCHEME_CALLBACK (calc_staff_staff_spacing, (SCM));
+ DECLARE_SCHEME_CALLBACK (calc_pure_staff_staff_spacing, (SCM, SCM, SCM));
+ DECLARE_SCHEME_CALLBACK (calc_pure_relevant_grobs, (SCM));
+ DECLARE_SCHEME_CALLBACK (calc_pure_relevant_items, (SCM));
+ DECLARE_SCHEME_CALLBACK (calc_pure_relevant_spanners, (SCM));
+ DECLARE_SCHEME_CALLBACK (calc_pure_y_common, (SCM));
+ static SCM internal_calc_pure_relevant_grobs (Grob *, const string&);
+ static Interval relative_group_extent (vector<Grob *> const &list,
+ Grob *common, Axis);
+ static Interval relative_maybe_bound_group_extent (vector<Grob *> const &list,
+ Grob *common, Axis, bool);