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Date: Sat, 26 May 2007 13:50:04 +0200
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Subject: $var::$static
From: bart@mediawave.nl (Bart de Boer)

Hi all,

I'd like to be able to do the following:


<?php

class Base {

	public static $var = 'hello';

	public function someFunc() {
		echo self::$var; // Currently maps to Base::$var
		echo $this::$var; // Should map to Child::$var
	}

}

class Child extends Base {

	public static $var = 'hello';

}

$class = 'Child';

$obj = new $class(); // This works.

echo $class::$var; // This doesn't. Should map to Child::$var


?>


...in other words: I'd like to be able to access static class variables 
from inside an instance of the Base and/or Child classes. I'd also like 
to be able to access them dynamically. ($className::$variable)

The only way to do this at the moment (to my knowledge at least) is to 
create functions in the Child class that returns its static variables. 
The downside of this is that those functions most likely will be very 
common (in my case they are) and should therefore belong in the base 
class. Hence: $this::$variable

At the moment there is no way to access static variables from outside of 
the class dynamically. As a workaround for this I'm currently creating a 
temporary instance (new $type()) to access them dynamically with a 
__get() function in all the derived child classes.

There are ways to do it with class constants and the constant functions. 
But it's not very elegant and class constants can't hold arrays and/or 
objects.

I have no idea what the implications would be. Just thought it would be 
a nice addition to the language. :) Hope I didn't overlook some existing 
PHP feature that already allows me to do this. :|


Cheers,

Bart de Boer