Function list_flat_map

test/flat_map_unittest.cpp:580–603

template <typename Key, typename Value, typename OnPause>
static void list_flat_map(std::vector<Key>* keys,
                          const butil::FlatMap<Key, Value>& map,
                          size_t max_one_pass,
                          OnPause& on_pause) {
    keys->clear();
    typedef butil::FlatMap<Key, Value> Map;
    size_t n = 0;
    for (typename Map::const_iterator it = map.begin(); it != map.end(); ++it) {
        if (++n >= max_one_pass) {
            typename Map::PositionHint hint;
            map.save_iterator(it, &hint);
            n = 0;
            on_pause(hint);
            it = map.restore_iterator(hint);
            if (it == map.begin()) { // resized
                keys->clear();
            }
            if (it == map.end()) {
                break;
            }
        }
        keys->push_back(it->first);
    }
}

typedef butil::FlatMap<uint64_t, uint64_t> PositionHintMap;