Instead of throwing an exception when the queue is empty, the reader thread now blocks itself on the condition variable.

当队列是空的时候，读线程现在并不抛出异常，而是在条件变量上阻塞自身。

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For example, you can switch off the small tables in Figure 7 for heading and information objects with a simple condition, or you can automatically leave out empty table entries.

例如，您可以关闭图7中的小表格，以让表头信息以一种简单的状态显示，或者您可以忽略空白的表格条目。

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This program begins by first checking a boundary condition -- whether or not the list is empty.

这个程序首先检查边界条件 —— 列表是否为空。

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Riley suffers from gastroparesis, a nasty condition in which the stomach cannot empty itself, causing nausea, vomiting and pain.

FORBES: Medical Insurance

As I settled into the car, a battered Toyota Solara, Lanier apologized for the condition of the front seat, the footwell of which was cluttered with old magazines, half-empty plastic water bottles, and a squashed box of tissues.

NEWYORKER: The Visionary