Wednesday, July 16, 2008

static classes

There is a proposal for static classes in the official php wiki. Interesting? Yes, in some way, but in no way that i like. If you are one of the code monkeys that discovered object oriented programming in some depth, you probably dislike static like me. If not, my further explanation may give you a clue.

Static is evil. Not enough explanation? Ok.

Static is evil because it exists. Still not enough?

Static is evil because it has been invented. *grmbl* I'll try the long route...

Let us start with the abbreviation OOP. The words Object Oriented Programming gives me the feeling that it has to do with objects. And objects are instantiated from classes. But the evil static declared stuff don't do anything to objects, it just belongs to the class and not the instance. (Ok, in PHP it's not exactly like that but it's the way it should be.)

So does all the static stuff has anything to do with OOP? Uhm, no. Can we make it more OOP? "We could make interfaces for static classes available! It's totally OOP!" Yes it's OOP, but it won't help. Why create an interface based static class if you can't replace it with another implementation? That's the idea of interfaces! "We can replace a class by an namespace import? Or we can call_user_func() all the time?" Oh, please! We have all this already with objects! Interfaces are useless for static classes. We can mimic abstract and singleton behaviour - for it's rare uses - in userland.

Static only exists to make old-school procedural programmers feel nice. You don't really need it in OOP and you don't need a even more complex static magic on earth. Actually all the static stuff could be thrown away with namespaces and closures for regular functions. Can you imagine?

Don't get me wrong, i use static methods sometimes and i love functions. But static classes would be a change in the wrong place.

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