[SyS]

Quote:

Originally Posted by Nathan94 Hello sampers, I was wondering what's the difference between "#define something 5" and "#define something (5)"?

If it's a single constant there is no difference.But if it was an expression for example

PHP Code:

#define EIGHT_PLUS_TWO 8+2 


and

PHP Code:

#define EIGHT_PLUS_TWO (8+2) 


are different.

lets see the first case

PHP Code:

#define EIGHT_PLUS_TWO 8+2
main(){
    new result = 2 * EIGHT_PLUS_TWO;
    ASSERT(20==result);//will fail as result is 18
} 


the above one is expanded to

Code:

new result = 2 * EIGHT_PLUS_TWO = 2 * 8+2 = 16+2 = 18 as per operator precedence

But in the second case

PHP Code:

#define EIGHT_PLUS_TWO (8+2)
main(){
    new result = 2 * EIGHT_PLUS_TWO;
    ASSERT(20==result);//will pass as one in parentheses is evaluated first
} 


is expanded to

Code:

result = 2 * EIGHT_PLUS_TWO = 2 * (8+2) = 2*(10) = 20 as per operator precedence