宏问题，带有多个语句

Question

#define RUN_SOME_STUFF(...) {                                        \
            int x = 0;                                               \
            printf("[INFO] Do some stuff here ... %d\n", ++x);       \
            {__VA_ARGS__}                                            \
            printf("[INFO] end some stuff here\n");                  \
        }

How I'm using it:

...
RUN_SOME_STUFF(
{
    // middle:
    int y;
    y = 100;
    printf("Middle\n"); 
});
...

Now, I know that this is considered as a (very) ugly macro, but that's the main reason i'm asking for help.

The first problem with this is, if appears any type of error, the compiler will show the last line of the macro, as the incorrect line. The printings are just examples to simplify the problem (in both code snippets), so there might be 20 line of complex, nested code, in which case that is very annoying.

The second one is that the __LINE__ is resolved the same incorrect way

& I'm sure there are many more ...

1. Are there any way to correct the above problems, so that the lines are correctly resolved? (some sort of compilator option maybe?, I'm using VS2008/2010)

2. If there's no way to make it with macro in a "cute" way, do I have any other options to do this? Simply, I just want to run some code "around"(before and after) some other code.

Edit: I would use this macro often, always with different "middle" content, so I can't write an inline function every time.

Answer 1

You can split the macro in two pieces. Not pretty, but it works when the macros are paired. Below both RUN_BEGIN; and RUN_END; are written so that they need a semicolon.

#define RUN_BEGIN \
    do { \
        int x = 0;   \
        printf("[INFO] Do some stuff here ... %d\n", ++x);  \
        {  \
            (void)0

#define RUN_END  \
        } \
        printf("[INFO] end some stuff here: %d\n",x ); \
    } while (0)

Answer 2

You probably would have better luck using function pointers . I haven't compiled this, but something like:

void runSomeStuff(void (*stuff)(void))
{
    int x = 0;                                                   
    printf("[INFO] Do some stuff here ... %d\n", ++x);       
    (*stuff)();                                           
    printf("[INFO] end some stuff here\n");    
}