Comma in C/C++ macro

by

If you can’t use parentheses and you don’t like Mike’s SINGLE_ARG solution, just define a COMMA:

#define COMMA ,

FOO(std::map<int COMMA int>, map_var);

This also helps if you want to stringify some of the macro arguments, as in

#include <cstdio>
#include <map>
#include <typeinfo>

#define STRV(...) #__VA_ARGS__
#define COMMA ,
#define FOO(type, bar) bar(STRV(type) \
    " has typeid name \"%s\"", typeid(type).name())

int main()
{
    FOO(std::map<int COMMA int>, std::printf);
}

which prints std::map<int , int> has typeid name "St3mapIiiSt4lessIiESaISt4pairIKiiEEE".

More Related Contents:

  1. Can we have recursive macros?
  2. How to identify platform/compiler from preprocessor macros?
  3. Escaping a # symbol in a #define macro?
  4. macro definition containing #include directive
  5. Can I redefine a C++ macro then define it back?
  6. Confused by squaring macro SQR in c [duplicate]
  7. How to tame the Windows headers (useful defines)?
  8. Expand macro inside string literal
  9. Which of the following implementations is faster? [closed]
  10. Why are #ifndef and #define used in C++ header files?
  11. Are typedef and #define the same in c?
  12. Combining C++ and C – how does #ifdef __cplusplus work?
  13. Define preprocessor macro through CMake?
  14. What is the worst real-world macros/pre-processor abuse you’ve ever come across?
  15. Optional Parameters with C++ Macros
  16. MSVC++ variadic macro expansion
  17. Multi line preprocessor macros
  18. Instantiate class from name?
  19. C++ preprocessor: avoid code repetition of member variable list
  20. How to make a variadic macro for std::cout?
  21. Are C++ Templates just Macros in disguise?
  22. Is there a way to get function name inside a C++ function?
  23. Reason why not to have a DELETE macro for C++
  24. When can you omit the file extension in an #include directive?
  25. C++ type registration at compile time trick
  26. Concat two `const char` string literals
  27. What does ## in a #define mean?
  28. How to find out cl.exe’s built-in macros
  29. How can you compare two character strings statically at compile time
  30. How do I run the preprocessor on local headers only?

Leave a Comment