<?
class class_root
{
	var $a;
	var $b;
	function class_root()
	{
		echo get_class($this)." Created<br>";
	}
}

class db_class extends class_root
{
	var $owner;
	function db_class($ow)
	{
		$this->class_root();
		$this->owner=$ow;
	}
}

class adm_class extends class_root
{
	var $owner;
	function adm_class($ow)
	{
		$this->class_root();
		$this->owner=$ow;
	}
	function kkk()
	{
		echo get_class($this->owner)."<br>";
		echo get_class($this->owner->adm)."<br>";//Undefined ??? ... must be object
		echo get_class($this->owner->db)."<br>";//Undefined ??? ... must be object
		$this->owner->adm->kkk();
	}
}

class super_class extends class_root
{
	var $s;
	var $adm;
	var $db;
	function super_class()
	{
		$this->class_root();
		$this->adm=new adm_class(&$this);
		$this->db=new db_class(&$this);	
	}
}

$sc=new super_class();
$sc->adm->kkk();

echo '-------';
?>

results:

super_class Created
adm_class Created
db_class Created
super_class


Fatal error: Call to a member function on a non-object in bla-bla-bla\1.php on line 35


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