public function getRenderedParameter($key, $escaper = null)
    {
        $subject = $this->getParameter($key);
        preg_match_all('/{{([a-zA-Z0-9\.\-\_]+)}}/', $subject, $matches);
        $parameterList = $matches[1];
        foreach ($parameterList as $parameterKey) {
            $val = $this->getParameter($parameterKey);
            if ($val) {
                if (is_callable($escaper)) {
                    $val = $escaper($val);
                }
                $subject = str_replace('{{'.$parameterKey.'}}', $val, $subject);
            } else {
                $subject = str_replace('{{'.$parameterKey.'}}', '', $subject);
            }
        }
        return $subject;
    }