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Date: Tue, 25 Apr 2006 15:15:52 +0200
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Subject: Re: [PHP-DEV] Static properties
From: jochem@iamjochem.com (Jochem Maas)

Petar Nedyalkov wrote:
> On Tuesday 25 April 2006 14:30, Edin Kadribasic wrote:
> 
>>Hi,
>>
>>I was wondering if someone could enlighten me why it is not possible to
>>create on-the-fly static properties:
>>
>>php -r 'class foo{}; foo::$bar = 1;'
>>Fatal error: Access to undeclared static property:  foo::$bar in Command
>>line code on line 1
> 
> 
> This totally breaks the capsulation in the OO paradigm, so I find it the right 
> behaviour. Taking apart the fact that there's no compilation in PHP, it also 
> prevents capsulation and making a member variable of an object available only 
> after it's declaration in the class (except for stdClass) is correct for me. 
> I see this as "You can't redefine the model at runtime".

Rubys allows exactly that and I'm sure your not going to say that Ruby is not an OO
language - Javascript likewise, in that it allows runtime definition/extension of
the model (granted it's prototype based rather than class based).

(anyone with the argument that PHP!=Ruby or PHP!=Javascript might consider that
PHP!="the OO paradigm")

I don't think the Fatal Error mentioned above is, from a endusers' POV,
what would be expected given the ability to define non-static properties on the fly...
If I had to guess as to what kind of error was raised I would have put my money on
E_STRICT - i.e. 'we don't recommend this way of doing things, but it doesn't hurt the
engine per se'

having said that I have never needed to define static properties on the fly, so it's
all rather academic. :-)

> 
> 
>>Was this not possible because of the engine implementation of the static
>>properties?
>>
>>Edin
> 
>