同时要注意，未定义的符号foo . fop . nope尽管没有赋值，但这样表示只是它本身的拼写。

Also notice that the undefined symbol foo.fop.nope simply stands for its own spelling, absent an assignment to the contrary.

youdao

未定义的符号与预处理器指令一起使用。

A symbol that was not defined was used with a preprocessor directive.

youdao

未定义的符号与预处理器指令一起使用。

A symbol that was not defined was used with a preprocessor directive.

youdao