+#include "pointer-group-interface.hh"
+
+#include "grob-array.hh"
+#include "grob.hh"
+
+int
+Pointer_group_interface::count (Grob *me, SCM sym)
+{
+ Grob_array *arr = unsmob<Grob_array> (me->internal_get_object (sym));
+ return arr ? arr->size () : 0;
+}
+
+void
+Pointer_group_interface::add_grob (Grob *me, SCM sym, SCM p)
+{
+ add_grob (me, sym, unsmob<Grob> (p));
+}
+
+void
+Pointer_group_interface::set_ordered (Grob *me, SCM sym, bool ordered)
+{
+ Grob_array *arr = get_grob_array (me, sym);
+ arr->set_ordered (ordered);
+}
+
+Grob_array *
+Pointer_group_interface::get_grob_array (Grob *me, SCM sym)
+{
+ SCM scm_arr = me->internal_get_object (sym);
+ Grob_array *arr = unsmob<Grob_array> (scm_arr);
+ if (!arr)
+ {
+ scm_arr = Grob_array::make_array ();
+ arr = unsmob<Grob_array> (scm_arr);
+ me->set_object (sym, scm_arr);
+ }
+ return arr;
+}
+
+Grob *
+Pointer_group_interface::find_grob (Grob *me, SCM sym, bool (*pred) (Grob *))
+{
+ Grob_array *arr = get_grob_array (me, sym);
+
+ for (vsize i = 0; i < arr->size (); i++)
+ if (pred (arr->grob (i)))
+ return arr->grob (i);
+
+ return 0;
+}
+
+void
+Pointer_group_interface::add_grob (Grob *me, SCM sym, Grob *p)
+{
+ Grob_array *arr = get_grob_array (me, sym);
+ arr->add (p);
+}
+
+void
+Pointer_group_interface::add_unordered_grob (Grob *me, SCM sym, Grob *p)
+{
+ Grob_array *arr = get_grob_array (me, sym);
+ arr->add (p);
+ arr->set_ordered (false);
+}
+
+static vector<Grob *> empty_array;
+
+vector<Grob *> const &
+ly_scm2link_array (SCM x)
+{
+ Grob_array *arr = unsmob<Grob_array> (x);
+ return arr ? arr->array () : empty_array;
+}
+
+vector<Grob *> const &
+internal_extract_grob_array (Grob const *elt, SCM symbol)
+{
+ return elt
+ ? ly_scm2link_array (elt->internal_get_object (symbol))
+ : empty_array;
+}
+
+vector<Item *>
+internal_extract_item_array (Grob const *elt, SCM symbol)
+{
+ Grob_array *arr = unsmob<Grob_array> (elt->internal_get_object (symbol));
+ vector<Item *> items;
+ for (vsize i = 0; arr && i < arr->size (); i++)
+ items.push_back (arr->item (i));
+
+ return items;
+}