Question

I have the following macro:

‎#define GTR(type) \‎
type type##_gtr(type a, type b) \‎
‎{ \‎
‎   return a > b ? a : b;\‎
‎}‎

I understand that it generates functions, but if GTR(unsigned int) expands outside main(), how do I call the generated function? _gtr(a, b) does not work…

Answer 1

GTR(unsigned) would expand to:

unsigned unsigned_gtr(unsigned a, unsigned b)
{
‎   return a > b ? a : b;
}‎

In that case, you should call unsigned_gtr(a, b).

GTR(unsigned int), however, would fail with a syntax error because you are having two separate tokens and the name of the function cannot be properly produced.