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C++ C++；连接_文件_和_行_宏？

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C++ C++；连接_文件_和_行_宏？,c++,C++,我希望我的异常消息包含有关异常位置的信息 所以我想要一些类似的东西 #define LOCATION __FILE__ " : " __LINE__ throw std::exception(std::string("ABCD. ") + LOCATION); 这个定义显然是错误的。如何实现这一点？您需要在两个级别展开该宏： #define S1(x) #x #define S2(x) S1(x) #define LOCATION __FILE__ " : " S2(__LINE__) 在

我希望我的异常消息包含有关异常位置的信息

所以我想要一些类似的东西

#define LOCATION __FILE__ " : " __LINE__

throw std::exception(std::string("ABCD. ") + LOCATION);
这个定义显然是错误的。如何实现这一点？

您需要在两个级别展开该宏：

#define S1(x) #x
#define S2(x) S1(x)
#define LOCATION __FILE__ " : " S2(__LINE__)
在将其传递给
#x
之前，需要将
uu行
展开为两个级别。首先，在像宏这样的函数中使用运算符
，它后面必须跟一个宏参数，但
\uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu
不是参数，所以编译器抱怨它是一个错误的运算符。另一方面，
\uuuuuuuuuuuuuuuuuuuuuuu本身是一个宏，包含当前行号，在将其与
一起使用之前，应将其扩展为数字，否则，您将获得字符串
“\uuuuuuuuuuuuuuuuuu”


宏
S2（\uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu？提前谢谢！Boost会这样做，以防您不想创建自己的宏S1和S2。@sree:#定义位置std:：string（PRETTY_FUNCTION）+“：：”+std:：string（FILE）+“：“+std:：string（S2（LINE））@adiog当要为异常（即在函数中使用）请求字符串时，您的建议在此处出错：
char foo[]=LOCATION在文件范围和函数中。