Function empty

src/UtilsCtrl/ThreadPool/Queue/UAtomicPriorityQueue.h:77–80

* 判定队列是否为空 * @return */

     * @return
     */
    [[nodiscard]] CBool empty() {
        CGRAPH_LOCK_GUARD lk(mutex_);
        return priority_queue_.empty();
    }

    CGRAPH_NO_ALLOWED_COPY(UAtomicPriorityQueue)