protected function getKnownFormat(string $formatName)
    {
        $knownFormats = [
            "email" => "/^([a-z0-9\+_\-]+)(\.[a-z0-9\+_\-]+)*@([a-z0-9\-]+\.)+[a-z]{2,}$/ix",
            "swiftCode" => "/^[A-Za-z]{6}[A-Za-z0-9]{2}[0-9A-Za-z]{0,3}$/",
            "uri" => "/^\w+:(\/\/)?[^\s]+$/",
            "url" => "/^((\w+:)?\/\/[^\s\/]+)?(\/[^\s]+)*\/?$/",
        ];

        if (array_key_exists($formatName, $knownFormats)) {
            return $knownFormats[$formatName];
        } else {
            return null;
        }
    }