This returns a new empty class to which I can add attributes.

它返回一个新的空类，我能向此空类添加属性。

youdao

The compiler still has to allocate space for the empty class, right?

编译器仍然必须为空类分配空间，对吧？

youdao

Note that when the first element is an empty class, compressed_pair_imp returns *this.

请注意，当第一个元素为空类时，compressed_pair_imp 返回 *this。

youdao

Right now it's empty, actually it's not quite empty, it has a pointer back to the class.

当我调用了这个类的，定义声明的时候，它在内存中的特定点。

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Dead center was a long table, surrounded by approximately twenty chairs, and, on the table, empty and half-empty cups, a few books, class logs, and some pamphlets.

NEWYORKER: Waiting

Despite the desirability of lie-flat beds, entertainment and fancy-meal service in business class, there are lots of empty seats to auction off.

WSJ: El Al, Virgin Atlantic Are Airlines That Auction Upgrades to Business Class