1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 | #include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <assert.h>
// WRONG (naïve)
#define FIVE_PLUS(n) 5 + n
int main(int argc, char* argv[]) {
printf("%d\n", FIVE_PLUS(100)); // ⇒ 105
// Preprocessor will replace FIVE_PLUS(100) with 5 + 100.
// This will NOT work as you expect.
printf("%d\n", 1000 * FIVE_PLUS(100));
// Preprocessor will replace FIVE_PLUS(100) with 5 + 100.
// Statement will become:
// printf("%d\n", 1000 * 5 + 100);
// Expect: 105000 but that's not what we will get.
// Actual: 5100
return EXIT_SUCCESS;
}
/* vim: set tabstop=4 shiftwidth=4 fileencoding=utf-8 noexpandtab: */
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