void fut_wait(){
thread::id tid = this_thread::get_id();
while(fut.valid()){
fut.wait();
bool ret = fut.get();
COUT << tid << " ret:" << ret << endl;
}
}
void t_future(){
//NOTICE("fut.get");
//fut.get();
NOTICE("fut.wait");
fut.wait();
thread t1(fut_wait), t2(fut_wait), t3(fut_wait);
while(true){
prom = promise<bool>();
fut = prom.get_future();
sleep(2);
prom.set_value(false);
sleep(3);
}
t1.join();
t2.join();
t3.join();
}