WebApr 10, 2024 · Macros are expanded by the preprocessor during preprocessing. c. #ifdef, #ifndef, #if, #else, #elif, and #endif: These directives are used for conditional compilation. They allow the preprocessor to include or exclude sections of code based on whether a certain macro is defined or not, or based on the value of an expression. Include Guards WebMar 2, 2016 · Since you added the C++ tag not using macros is a valid answer. If you just want to talk about the pre-processor just tag it as pre-processor and not C++ – Martin York Nov 22, 2010 at 23:20 15 @Martin: The preprocessor is as much a part of C++ as the STL is; should questions about the STL be tagged [stl] and not [c++] too?
c++ - How can I retrieve the last argument of a C99 variadic macro …
WebAug 17, 2011 · This question describes a way to suppress the unused parameter warning by writing a macro inside the function code: Universally compiler independent way of implementing an UNUSED macro in C/C++ But I'm interested in a macro that can be used in the function signature: void callback (int UNUSED (some_useless_stuff)) {} WebJun 3, 2014 · The C preprocessor throws an error because the STATIC_ASSERT macro only takes one parameter. The two main solutions to this problem are to use double parentheses and, more recently, to use variadic macros: // Invoke the macro this way... hill wallpaper
Preprocessor fails due to -
WebMar 1, 2012 · You can use a variadic macro and then pass the string format and the function parameters to it. The macro won't be exactly the same for every function (as … WebJan 25, 2024 · No, this is not possible. During translation, all preprocessing directives ( #define, #include, etc.) are executed before any macro expansion occurs, so if a macro expands into a preprocessing directive, it won't be interpreted as such - it will be interpreted as (invalid) source code. Share Improve this answer Follow answered Jan 24, 2024 at … WebJan 17, 2024 · From standard - §6.10.1p5. Preprocessing directives of the forms. # ifdef identifier new-line groupopt # ifndef identifier new-line groupopt. check whether the … hill walks near glasgow