C预处理器更换无法正常工作

Question

#include <stdio.h>
#define VAR cc

int main(void) {
    int ccc = 9;
    printf("hell loo %d", VARc);
    return 0;
}

我对这段代码的理解意味着预处理器找到的任何地方VAR都会替换它cc,因此printf会有一个正确定义的变量ccc,但代码会出错.有人可以请帮助

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编辑1

我得到的错误是

test.c: In function ‘main’:
test.c:16: error: ‘VARc’ undeclared (first use in this function)
test.c:16: error: (Each undeclared identifier is reported only once
test.c:16: error: for each function it appears in.)

Answer 1

那不行.预处理器适用于整个令牌,而不是字符串.

如果要连接,可以执行以下操作:

#include <stdio.h>
#define VAR(End) cc##End // ## does token concatenation inside a pp macro

int main(void) {
    int ccc = 9;
    printf("hell loo %d", VAR(c));
    return 0;
}