+/* sortable */
+static gboolean wxgtk_tree_model_get_sort_column_id (GtkTreeSortable *sortable,
+ gint *sort_column_id,
+ GtkSortType *order);
+static void wxgtk_tree_model_set_sort_column_id (GtkTreeSortable *sortable,
+ gint sort_column_id,
+ GtkSortType order);
+static void wxgtk_tree_model_set_sort_func (GtkTreeSortable *sortable,
+ gint sort_column_id,
+ GtkTreeIterCompareFunc func,
+ gpointer data,
+ GtkDestroyNotify destroy);
+static void wxgtk_tree_model_set_default_sort_func (GtkTreeSortable *sortable,
+ GtkTreeIterCompareFunc func,
+ gpointer data,
+ GtkDestroyNotify destroy);
+static gboolean wxgtk_tree_model_has_default_sort_func (GtkTreeSortable *sortable);
+
+
+