Child class references static variable of parent instead of its own

Here's an OOP question that perplexes me. It seems PHP doesn't treat
static variables correctly in child classes.

class ABC {
public $regular_variable = "Regular variable in ABC\n";
public static $static_variable = "Static variable in ABC\n";

public function regular_function() {
echo $this->regular_variable;
}

public static function static_function() {
echo self::$static_variable;
}
}

class DEF extends ABC {
public $regular_variable = "Regular variable in DEF\n";
public static $static_variable = "Static variable in DEF\n";
}

$abc = new ABC();
$abc->regular_function();
ABC::static_function();

$def = new DEF();
$def->regular_function();
DEF::static_function();
?>

WHAT I EXPECTED:
Regular variable in ABC
Static variable in ABC
Regular variable in DEF
Static variable in DEF

ACTUAL OUTPUT:
Regular variable in ABC
Static variable in ABC
Regular variable in DEF
Static variable in ABC <--- This is different from what I expected

Anyone know why?

There are several examples of this bug (if it is one) in the comments
for the get_class() function: http://us.php.net/manual/en/function.get-class.php

Best regards,
Richard

Re: Child class references static variable of parent instead of itsown

The manual says that static variables are not inherited normally:

http://nl3.php.net/manual/pl/language.oop5.static.php

Best regards.

Re: Child class references static variable of parent instead of itsown

Richard K Miller wrote:

> Here's an OOP question that perplexes me. It seems PHP doesn't treat
> static variables correctly in child classes.

Google: PHP late static binding.

It *might* get fixed in PHP 6, but is unlikely to change in PHP 5.x
because it may break scripts that rely on the current behaviour.

-Toby

Re: Child class references static variable of parent instead of its own

On Aug 17, 3:04 pm, Dikkie Dik wrote:
> The manual says that static variables are not inherited normally:
>
> http://nl3.php.net/manual/pl/language.oop5.static.php
>
> Best regards.

Thanks for pointing that out; I hadn't noticed.

Minutes from a meeting about PHP 6 seem to indicate that this will be
fixed:

http://www.php.net/~derick/meeting-notes.html#late-static-bi nding-using-this-without-or-perhaps-with-a-different-name