public function includeScriptOnce($sFileName, $sType = null, $sId = null)
    {
        $command = array('cmd' => 'ino');

        if(($sType))
            $command['type'] = trim((string)$sType, " \t");

        if(($sId))
            $command['elm_id'] = trim((string)$sId, " \t");

        return $this->addCommand($command, trim((string)$sFileName, " \t"));
    }