The key here is the next-to-last line: the set-property tag.

这里的关键是倒数第二行：set - property标记。

youdao

Determines whether a given type is a function, possibly with additional properties as specified by a property tag.

判定一个给定的类型是否为函数，可以通过属性标签额外指定属性。

youdao

Determines whether a given type is a function pointer, possibly with additional properties as specified by a property tag.

判定一个给定的类型是否为函数指针，可以通过属性标签额外指定属性。

youdao

Although the property market had fallen, the price tag was still enormous.

CNN: JAPAN'S DOWNSIZING FABLE