C++ # is not followed by a macro parameter

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WebOct 28, 2024 · Argument substitution expansion only occurs if the parameter in the macro corresponds to one in the replacement list (and that parameter isn't stringified with the # … WebMar 25, 2006 · C++ and C). By definition a macro (the part after the #define) ends on the same line. This can be partially ameliorated by the use of continuation lines (where the …

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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 … WebJun 25, 2016 · To use proper C99 variadic macros, you should be compiling with a C compiler that supports C99 (like gcc), not a C++ compiler, since C++ doesn't have standard variadic macros. – Chris Lutz Mar 25, 2009 at 2:13 Well, I assumed C++ is a super set of C in this regard .. – hasen Mar 25, 2009 at 3:46 cannabis use meme cheech and chong employment

c++ - Macro to Get function name and parameter values from …

WebNov 19, 2024 · There are 2 problems with your macro definition: It uses incorrect syntax The name of a variable may be passed as a; in this case you cannot simply put the variable next to 2 string literals to do a concatenation. The latter problem can be solved by using a string and the + operator or simply using multiple printf s. WebMay 30, 2012 · do not enclose arguments of macro in parentheses in the macro body, so if those arguments are expressions, operators with different precedences in those … WebSep 26, 2024 · 1. I'm trying to write a macro that generates code for an object pool for any given class of objects in C. I keep getting error: '#' is not followed by a macro … cannabis use in united states

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c++ - Macro to Get function name and parameter values from within ...

WebJan 4, 2016 · Macros with Parameters (C++) navigation search Go Up to The Preprocessor Index The following syntax is used to define a macro with parameters: #define macro_identifier () Contents 1 Nesting Parentheses And Commas 2 Side Effects and Other Dangers 3 Converting Actual Arguments to … WebSometimes (like the Visual C++), the debugging info is extracted into a separate file - but you would need that file and know its format, to extract that info. And you would be getting only the debug info. Not the compiled code. The parameters are the way to go. cannabis use in pregnancy nhsWebApr 10, 2024 · I want to use macros or template metaprogramming to generate some code for me. So basically these enum values are 1 shifted by the index of enum I want to avoid any typos in case in future some adds a new enum value and I can simply define an array of string for the named enums and generate functions for it and return value based on the … fix leaky shut off valve bathroom

"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 … " - C++ # is not followed by a macro parameter

C++ # is not followed by a macro parameter

Web2 days ago · I want to call the show.py in my Qt project. The p_stdout should be hello, but I just get an empty string "", the exit code is 1, and the exit status is QProcess::NormalExit. This is my WebJun 9, 2024 · You can define a variadic macro in C++ like: #define FOO (x, ...) bar (x, __VA_ARGS__) But calling FOO as FOO (1) results in the macro expansion bar (1,) which is obviously a syntactical error and won't compile. Therefore GCC includes a GNU extension: #define FOO (x, ...) bar (x, ##__VA_ARGS__)

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WebNov 6, 2008 · C and C++ languages explicitly prohibit forming preprocessor directives as the result of macro expansion. This means that you can't include a preprocessor directive … 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)) {}

WebNov 20, 2024 · You can fix this with an extra "helper" macro: #define MAX_NAME_LEN 15 #define STRINGIFY (s) \ #s #define PRINT_CELL (x) \ printf (" %" STRINGIFY … WebJun 4, 2016 · A better way to avoid the warning is to use a dummy macro that expands to nothing, e.g. #define NOARG then you can use MY_MACRO (NOARG, bar, baz). – Rufflewind Jun 4, 2016 at 12:43 Add a comment Your Answer By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy Not the …

WebSep 25, 2015 · It's a pity that the defined operator is available only in the context of #if and #ifelse, but not for macro expansions. As it stands, I agree with rici about the solutions … 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 …

Webpasses two arguments to macro: array[x = yand x + 1]. If you want to supply array[x = y, x + 1]as an argument, you can write it as array[(x = y, x + 1)], which is equivalent C code. All …

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? fix leaky shower valve stemWebJan 4, 2016 · Such macros are called by writing. macro_identifier () in the subsequent source code. The syntax is identical to that of a … fix leaky shower faucet deltaWebMar 31, 2024 · How to redefine c++ macro with reduced parameters? Ask Question Asked 7 days ago Modified 5 days ago Viewed 54 times 0 I have following macros in an existing project, #define TRACE1 (attr,str,...) REL_LOG (attr, str, ##_VA_ARGS__) #define TRACE2 (str,...) REL_LOG (str, ##_VA_ARGS__) And they have been used like, cannabis use linked to schizophreniaWebApr 4, 2024 · (since C++11) Otherwise, the behavior is undefined. # and ## operators In function-like macros, a # operator before an identifier in the replacement-list runs the … fix leaky shower drainWebJun 22, 2011 · As JAB pointed, macros are different than functions, they do not require the type of arguments #define TRACERPTR (pReporter, eComponent, eLevel, sFormat, formatArgs...) \ if (pReporter != NULL) { pReporter->trace (eComponent, eLevel, sFormat, ##formatArgs); } Share Improve this answer Follow answered Jun 20, 2011 at 19:27 … cannabis use mental healthWebApr 13, 2024 · Then, we initialize each thread giving it the function to execute ** multiply_threading ** that has the following signature: ```c void multiply_threading(Matrix& result, const int thread_number, const Matrix& m1, const Matrix& m2); ``` The first parameter is the output matrix, The second parameter is the thread number (later on … fix leaky shut off valveWebJun 20, 2015 · You could get a clear compilation error if you converted the selected argument which is supposed to be a MACRO name to string using # (the pound sign) and compared it's first n characters with the expected prefix and if there is no match, printed an informative error. – AturSams Jan 7, 2014 at 16:01 1 cannabis use schizophrenia