defines take up less space

I was choosing whether or not to use defines or const ints, and I have reached a crossroad: Don't const ints take up space? Sure the size is un-noticeable, but still. Do people not use defines as much just because it isn't standard?

The compiler goes through and replaces occurances of a const int with the actual number, doesn't it?

>Do people not use defines as much just because it isn't standard?

defines are stanfdard.

>The compiler goes through and replaces occurances of a const int with the actual number, doesn't it?

if im not mistaken this is not guaranteed behavior and is dependant on the compiler, and how smart it is.

I always use defines. I've never used const variables except in parameters for functions and API's forcing me to.

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Originally posted by Stan100
I was choosing whether or not to use defines or const ints, and I have reached a crossroad: Don't const ints take up space? Sure the size is un-noticeable, but still. Do people not use defines as much just because it isn't standard?

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Unless you take the address of the const int, any good compiler will optimize it away unless you have all optimizations off.

People don't like #define because #define completely ignores any and all scope rules. A const int obeys all the usual laws of scope; a #define obeys none of them. It's thus easy for a #define to shoot your code to hell very quickly. A #define cannot be confined to one class, one function, or one namespace. A const int can. A #define will happily puke anywhere in the code that it can, including other namespaces, etc. You can use a #define and accidently break code that exists in a library far, far away.

Thus, you should ONLY use #defines when they are absolutely needed -- #defines can do things that const ints cannot (example, they can be used for conditional compilation of various sections of code).

define = good

const = used for other things