For tasks that execute code in a loop, it is common to check for interruption only once per loop iteration.
对于执行一个循环中的代码的任务,通常只需为每一个循环迭代检查一次中断。
2
However, even noncancelable tasks should attempt to preserve the interrupted status in case code higher up on the call stack wants to act on the interruption after the noncancelable task completes.