C++ macro without spaces

Question

I need a macro to expand to a c++ comment, is that possible?

I've got this:

#define SLASH(x,y) x y
#define OUT SLASH(/,/)

int main(int argc, char *argv[])
{
  OUT << "text";
  return 0;
}

And need to expand to this:

{
  // << "text";
  return 0;
}

I've also tried this:

#define SLASH(x) /x
#define OUT SLASH(/)

But the result is still the same:

int main(int argc, char *argv[])
{
  / / << "text";
  return 0;
}

Answer 1

No it's not possible because in C++ comments are removed before macros are expanded.

(See 2.1 of the standard, comment removal happens in phase 3, macro expansion in phase 4.)