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/* 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;
}
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