text: /* n_25.c:  Macro arguments are pre-expanded (unless the argument is an
          operand of # or ## operator) separately, that is, are macro-replaced
          completely prior to rescanning. */
  
  #include    "defs.h"
  
  #define ZERO_TOKEN
  #define MACRO_0         0
  #define MACRO_1         1
  #define TWO_ARGS        a,b
  #define sub( x, y)      (x - y)
  #define glue( a, b)     a ## b
  #define xglue( a, b)    glue( a, b)
  #define str( a)         # a
  
  main( void)
  {
      int     a = 1, b = 2, abc = 3, MACRO_0MACRO_1 = 2;
  
      fputs( "started\n", stderr);
  
  /* 25.1:    "TWO_ARGS" is read as one argument to "sub", then expanded to
          "a,b", then "x" is substituted by "a,b".    */
      assert( sub( TWO_ARGS, 1) == 1);
  
  /* 25.2:    An argument pre-expanded to 0-token.    */
  /*  ( - 1); */
      assert( sub( ZERO_TOKEN, a) == -1);
  
  /* 25.3:    "glue( a, b)" is pre-expanded.  */
      assert( xglue( glue( a, b), c) == 3);
  
  /* 25.4:    Operands of ## operator are not pre-expanded.   */
      assert( glue( MACRO_0, MACRO_1) == 2);
  
  /* 25.5:    Operand of # operator is not pre-expanded.  */
      assert( strcmp( str( ZERO_TOKEN), "ZERO_TOKEN") == 0);
  
      fputs( "success\n", stderr);
      return  0;
  }
  
  