public static function a($attr, $cont)
    {
        if (is_string($attr)) {
            $attr = array('href' => $attr);
        }

        return self::tag('a', $attr, $cont, array_merge(self::$common_attrib,
            array('href','target','name','rel','onclick','onmouseover','onmouseout','onmousedown','onmouseup')));
    }