Question

Before PHP 5.3 I was using the following home-made function to create enums :

function enum()
{
    for($enums = func_get_args(), $enum = reset($enums), $i = 1; $enum; $enum = next($enums), ++$i)
    {
        if(defined($enum)) throw new Exception($enum.' is already defined.');
        else define($enum, $i);
    }

} // enum()

And then :

enum('CONST0', 'CONST1', 'CONST2', ...);

With php 5.3 I can do that using const instead of define to benefit from namespaces. Is there a way I could modify this function to make it use the const keyword ?

Also I’m only using 5.3 to make my code look cleaner, if there must be a performance impact (i.e. using eval or stuffs like that), I’ll stick with the good old define.

I’ve already looked at this question : PHP and Enumerations but I didn’t find what I’m looking for.

Answer 1

You can’t use const keyword conditionally [see this very high voted answer].

If you want to namespace your constants, the best approach is to make them static fields of a class, taking advantage of magic __get and __set if you needed.

EDIT: no magic setters / getters in static context of course, you can come with a flexible solution anyway.