Is there a way to both check a macro is defined and it equals a certain value at the same time

Question

I regularly use object-like preprocessor macros as boolean flags in C code to turn on and off sections of code.

For example

#define          


        

Answer 1

Simply create a macro DEBUG_PRINT that does the actual printing:

#define DEBUG_PRINT(n, str)    \
                               \
  if(n == 1)                   \
  {                            \
    printf("%s", str);         \
  }                            \
  else if(n == 2)              \
  {                            \
    do_something_else();       \
  }                            \
                               \
#endif


#include 

int main()
{
  DEBUG_PRINT(1, "testing");
}

If the macro isn't defined, then you will get a compiler error because the symbol is not recognized.