c++ std::thread + lambda 實現計時器

bool wait_for_wake = false;
std::mutex process_mutex;
std::condition_variable_any process_cond;
std::unique_lock<std::mutex> lock(process_mutex);
auto Timer = [&process_mutex, &process_cond](const int &wait_time) {
  std::this_thread::sleep_for(std::chrono::milliseconds(wait_time));
  process_cond.notify_one();
};

// use
auto wait_time = 50; 
std::thread(Timer, wait_time).detach();
wait_for_wake = true;

while (wait_for_wake) {
  process_cond.wait(lock);
  wait_for_wake = false;
}