c - How to use the following preprocessor statement - 


#define is_this_correct(x) if(x){}

i have preprocessor statement defined in project. trying understand how use function.

#define is_this_correct(x) if(x){}

it can used check if x (any value) not 0 or not empty string etc. can following

is_this_correct("hello") else puts("the string empty");

you'd better surround x pair of braces more safety:

#define is_this_correct(x) if((x)){}

i suggest rename preprocessor statement it_is_correct or is_correct more readability.


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