+
+map_iter_t * map_iter_begin (map_t *map, void *key) {
+ map_iter_t *iter = nbd_malloc(sizeof(map_iter_t));
+ iter->impl = map->impl;
+ iter->state = map->impl->iter_begin(map->data, key);
+ return iter;
+}
+
+uint64_t map_iter_next (map_iter_t *iter, void **key_ptr) {
+ return iter->impl->iter_next(iter->state, key_ptr);
+}
+
+void map_iter_free (map_iter_t *iter) {
+ iter->impl->iter_free(iter->state);
+ nbd_free(iter);
+}