private function parseCallablePlaceholders($fragment)
    {
        if (strpos($fragment, "{") !== false) {
            foreach ($this->params as $placeholder => $value) {
                if (strpos($fragment, "{" . $placeholder . "}") !== false) {
                    $fragment = str_replace("{" . $placeholder . "}", ucwords(str_replace("-", " ", $value)), $fragment);
                }
            }
        }

        return $fragment;
    }