可变常量宏，数值常量前应为')' [英] Variadic macro expected ')' before numeric constant

问题描述

这是实际的宏:

#ifdef DEBUG                                                                   
#define debug(funcname, format, ...) \                                         
        printf(BOLD UNDERLINED REVERSE \                                    
        "DEBUG IN " __FILE__ \                                             
        " LINE " __LINE__ ":" \                                            
        RESET UNDERLINED REVERSE \                                         
        "In " funcname \                                                   
        RESET REVERSE format RESET, ##__VA_ARGS__)                         
#else                                                                          
#define debug(funcname, format, ...)                                           
#endif                                                                        

所有使用的常量都是定义明确的字符串常量.我用类似这样的名称来称呼它:

Where all the constant used are well defined string constants. I call it with something like:

char message[] = "Hello StackOverflow !\n";
debug("main()", "Message: %s\n", message);

但是我收到消息

错误:数值常量前应有'"debug("main()"，"Message:"，message); 放在右括号中.

这很奇怪，因为我首先测试了宏，而现在该项目已经与团队一起进行了，因此无法正常工作...

It is weird because I first tested the macro, and now that the project has advanced with the team it doesn't work...

推荐答案

那是因为

 " LINE " __LINE__ ":"

扩展为语法无效

 " LINE " 42 ":"

因为 __ LINE __ 是整数，而不是可以串联的字符串文字.

since __LINE__ is an integer, not a string literal that can be concatenated.

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