อยากทราบวิธีการใช้ class แบบเหมือน extends แต่ไม่ได้ extends

<?php
    $HTML_CLASS = 'H1';
    abstract class H{
        /**
         * print Class name
         */
        abstract function e();
        /**
         * @return string Class name
         */
        abstract function r();
    }
    class H1 extends H{
        function e(){echo 'H1';}
        function r(){return 'H1';}
    }
    class H2 extends H{
        function e(){echo 'H2';}
        function r(){return 'H2';}
    }
    /**
     *
     * @global string $HTML_CLASS
     * @return H
     */
    function html(){
      global $HTML_CLASS;
      return new $HTML_CLASS;
    }
    $h = html();
    $h->e();
?>

<?php
    $HTML_CLASS = 'H1';
    class H{
        private $obj;
        public function __construct() {
            global $HTML_CLASS;
            $this->obj = new $HTML_CLASS;
        }
        /*
        public function e(){
            $args=func_get_args(); return call_user_method_array(__FUNCTION__,$this->obj,$args);
        }
        public function r(){
            $args=func_get_args(); return call_user_method_array(__FUNCTION__,$this->obj,$args);
        }
        public function p($s){
            $args=func_get_args(); return call_user_method_array(__FUNCTION__,$this->obj,$args);
        }
        */
        public function __call($name, $params){
            call_user_method_array($name, $this->obj, $params);
        }
    }
    class H1 extends H{
        public function  __construct(){}
        public function e(){echo 'H1';}
        public function r(){return 'H1';}
        public function p($s){echo $s.'__H1';}
    }
    class H2 extends H{
        public function  __construct(){}
        public function e(){echo 'H2';}
        public function r(){return 'H2';}
        public function p($s){echo $s.'__H2';}
    }
    $h = new H();
    $h->e();
    $h->p('ddd');
?>

class html {
	private $tag;
	
	public function __construct() {
		global $cfg;
		$this->tag = new $cfg['html_ver']; // ควรเป็น new html4;
	}// __construct
	
	public function __call($name, $arguments) {
		global $cfg;
		call_user_method_array($name, $this->tag, $arguments);
		//return $newhtml->$name($arguments);
	}// __call
	
}

class html4 extends html {
	
	/**
	* ทุกๆ function $option ให้ใส่เป็นแบบ array เช่น $html->tag(array('class'=>'classname'));
	*/
	public function br($option='') {
		$output = "<BR";
		if ($option != null) {
			foreach ($option as $attr=>$val) {
				$output .= " ".$attr."=\"".$val."\"";
			}
		}
		$output .= ">";
		return $output;
	}// br