40 lines
705 B
C
40 lines
705 B
C
// C preprocessor - conditional inclusion
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// Source: https://en.cppreference.com/w/c/preprocessor/conditional
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#define ABCD 2
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#include <stdio.h>
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int main(void)
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{
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#ifdef ABCD
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printf("1: yes\n");
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#else
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printf("1: no\n");
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#endif
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#ifndef ABCD
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printf("2: no1\n");
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#elif ABCD == 2
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printf("2: yes\n");
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#else
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printf("2: no2\n");
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#endif
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#if !defined(DCBA) && (ABCD < 2 * 4 - 3)
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printf("3: yes\n");
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#endif
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// C23 directives #elifdef/#elifndef
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#ifdef CPU
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printf("4: no1\n");
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#elifdef GPU
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printf("4: no2\n");
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#elifndef RAM
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printf("4: yes\n"); // selected in C23 mode, may be selected in pre-C23 mode
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#else
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printf("4: no3\n"); // may be selected in pre-C23 mode
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#endif
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}
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