Question: ```
#define IS_THIS_CORRECT(X) if(X){}

```

I have this preprocessor statement defined in my project. I am trying to understand how to use this function.

Answer: 
```
#define IS_THIS_CORRECT(X) if(X){}

```

It can be used to check if `X` (any value) is not zero or is not an empty string etc. You can do the following

```
IS_THIS_CORRECT("Hello")
else puts("The string is empty");

```

You'd better surround `X` with another pair of braces for more safety:

```
#define IS_THIS_CORRECT(X) if((X)){}

```

I suggest you to rename this preprocessor statement as `IT_IS_CORRECT` or even `IS_CORRECT` for more readability.
I'm guessing, but the only way this makes any sense to me is if it's supposed to be used as

```
IS_THIS_CORRECT(foo) else { do_something(); }

```

Still weird, though.