20000209-2.c

this is a gcc file, you can download it and learn its usetility, for further detail please look at t

/* { dg-do compile } */
/* { dg-options "-Wall" } */
/* Distilled from glibc sources.  Tests preprocessor corner cases.
   Since it uses rest args, we must turn off -pedantic-errors.  */

#define NO_PAREN(rest...) rest
#define DEFINE_CATEGORY(category, items) \
const int _nl_value_type_##category[] = { NO_PAREN items }

DEFINE_CATEGORY
(
 LC_COLLATE,
 (
   1,
   2,
   3,
  ));

DEFINE_CATEGORY(LC_CTYPE, (1, 2, 3));