stringification

This question already has an answer here: What are the applications of the ## preprocessor operator and gotchas to consider? 13 answers I have a set of target macros for which I want to generate aliases based on a choosing macro, like so: Choosing macro: #define I2C_MODULE 1 Alias macros (conceptual form): #define I2C_MODULE_BASE I2C<Value of I2C_MODULE>_BASE #define I2C_MODULE_NVIC INT_I2C<Value of I2C_MODULE> Target macros (from an external file out of my control): #define INT_I2C0 24 #define INT_I2C1 53 ... #define I2C0_BASE 0x40020000 #define I2C1_BASE 0x40021000 ... I wanted to have the

This is my first post, so if I'm being too vague or giving information that everyone would intuitively assume, please let me know. I'm very new to writing in C and am just trying to get a better understanding of preprocessing. I'm writing a simple program that can take in arguments either directly from the console using gcc -Wall -std=c99 -DSEED=argument , where my argument should be a an integer, or if the -D is not defined the user will input it. The SEED value is simply used in srand() . I'm very confused why my code will not compile if I put in an -DSEED=a as my argument while if I put

I would like to create a C pre-processor macro that will single-quote the argument. Just like the common used #X . I want Q(A) to be expanded to 'A' . I am using gcc on Linux. Does any one have an idea? I know # double-quotes. I am looking for a similar mechanism for single-quoting. The best you can do is #define Q(x) ((#x)[0]) or #define SINGLEQUOTED_A 'A' #define SINGLEQUOTED_B 'B' ... #define SINGLEQUOTED_z 'z' #define Q(x) SINGLEQUOTED_##x This only works for a - z , A - Z , 0 - 9 and _ (and $ for some compilers). Actually, #X double quotes its argument, as you can see with the following

Is it possible in C++ to stringify template arguments? I tried this: #define STRINGIFY(x) #x template <typename T> struct Stringify { Stringify() { cout<<STRINGIFY(T)<<endl; } }; int main() { Stringify<int> s; } But what I get is a 'T', and not an 'int'. Seems that the preprocessors kicks in before template resolution. Is there any other way to do this? Is there any way for the preprocessing to take place after template resolution? (Compiler is VC++). You could try typeid(T).name() Edit : Fixed based on comments. Cat Plus Plus You could use some template magic. #include <iostream> template

In our legacy code, as well as our modern code, we use macros to perform nifty solutions like code generations, etc. And we make use of both the # and ## operators. I am curious how other developers use macros to do cool things, if they use them at all. In C, it's common to define macros that do some stuff getting the verbatim argument, and at the same time define functions to be able to get the address of it transparently. // could evaluate at compile time if __builtin_sin gets // special treatment by the compiler #define sin(x) __builtin_sin(x) // parentheses avoid substitution by the macro