+let global_aliases_db = ref [];;
+let rev_includes_map_db = ref [];;
+
+let global_aliases u =
+ try List.assoc u !global_aliases_db
+ with Not_found ->
+ let db = ref [] in
+ global_aliases_db := (u,db)::!global_aliases_db;
+ db
+;;
+
+let rev_includes_map u =
+ try List.assoc u !rev_includes_map_db
+ with Not_found ->
+ let db = ref NUri.UriMap.empty in
+ rev_includes_map_db := (u,db)::!rev_includes_map_db;
+ db
+;;
+