【C】##拼接和#拼接

举例1

/*
C++的小知识（## 连接符与# 符）
https://blog.youkuaiyun.com/qq_35240555/article/details/80264089
*/

/*
hlong@Compile:~/test/c$ gcc main.c -o main
hlong@Compile:~/test/c$ ./main
result9 = 9
*/

#include <stdio.h>


#define paster(n) printf("result"#n" = %d\n", token##n)

int main(void)
{
	int token9 = 9;
	paster(9);
	
	return 0;
}

 

举例2

/*
C++的小知识（## 连接符与# 符）
https://blog.youkuaiyun.com/qq_35240555/article/details/80264089
*/

/*
hlong@Compile:~/test/c$ gcc main1.c -o test
hlong@Compile:~/test/c$ ./test             
hi_run is running
hello_run is running
*/

#include <stdio.h>

/* 宏定义总入口 */
#define run(comp)\
do{\
	comp##_run();\
}while(0)


void hi_run(void)
{
	printf("hi_run is running\n");
}

void hello_run(void)
{
	printf("hello_run is running\n");
}


int main(void)
{
	run(hi);
	run(hello);
	
	return 0;
}