When an event occurs, the object associated with that event emits a signal to inform the main loop that it has occurred.

当事件发生时，与这个事件对应的对象发出信号，通知主循环事件已经发生。

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The main loop then looks through its internal mapping table between its signals and handlers, also called callbacks, and calls the handlers registered for the given signal on the given object.

然后主循环查询自己的信号和处理程序之间的内部映射表，也叫做回调，并调用注册到指定对象的指定信号的处理程序。

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It then sets an internal flag called suspended to true and enters a loop, waiting to be sent a signal to resume.

然后将叫作suspended的内部标志设置为true，然后进入循环，等候别人发送信号，以继续其操作。

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What it seems to boil down to is this: being left out of the loop is perceived as a signal that one has low status or standing in the group.

FORBES: The Hidden Dangers of Leaving Someone Out of the Loop

It is also a force in digital loop carriers, which convert multiple voice calls into a single digital signal and can use either copper or fiber-optic cables.

FORBES: Laggard

The unique Loop Recorder also allows DJs to capture and overdub audio loops from the live mix, cue signal or an external input on the fly, and drop them back into the mix at any time.

ENGADGET: Traktor Kontrol S4 hardware interface set to make the scene this winter