gistfile1.cpp

#include <cstdio>

#ifdef DECLARE_PRINTER_
#error "The macro DECLARE_PRINTER_ is duplicated."
#else
#define DECLARE_PRINTER_(SECTION, VALUE_NAME)   \
  void print_##SECTION##_##VALUE_NAME() {       \
    printf("%s - %s\n", #SECTION, #VALUE_NAME); \
  }
#endif  // DECLARE_PRINTER_

DECLARE_PRINTER_(foo, bar);
DECLARE_PRINTER_(bar, baz);

#undef DECLARE_PRINTER_

int main() {
  print_foo_bar();
  print_bar_baz();
  return 0;
}