<?php
abstract class page{
    public $head;
    public $content;
    public $foot;

    function __construct($head, $content, $foot){
       $this->head = $head;
       $this->content = $content;
       $this->foot = $foot;
    }
   
    public function getPage(){
       $smarty = new Smarty();
    }  
}

class login extends page{
   public function __construct($data){
      parent::__construct("login head", $data, "login foot");
   }
}
?>

<?php
class talker{

    private $data = 'Hi';

    public function & get(){
        return $this->data;
    }
   
    public function out(){
        echo $this->data;
    }    

}

$aa = new talker();
$d = &$aa->get();

$aa->out();
$d = 'How';
$aa->out();
$d = 'Are';
$aa->out();
$d = 'You';
$aa->out();
?>