Token pasting and __LINE__

Question

I\'m writing a simple macro to show TRACE information.

This is what I\'m using ,

#ifdef __DEBUG__
#define TRACE  { PrintErrorMsg(\"Trace exception at         


        

Answer 1

You need this kind of silliness, unfortunately.

#include 

#define TRACE2(f,l) printf("I am at file: " f " and line: " #l "\n")
#define TRACE1(f,l) TRACE2(f,l)
#define TRACE() TRACE1(__FILE__, __LINE__)

int main(void)
{
    TRACE();
    TRACE();
}

I am at file: test.cpp and line: 9
I am at file: test.cpp and line: 10