Negotiation\LanguageNegotiator::match PHP Метод

    protected function match(AcceptHeader $acceptLanguage, AcceptHeader $priority, $index)
    {
        if (!$acceptLanguage instanceof AcceptLanguage || !$priority instanceof AcceptLanguage) {
            return null;
        }
        $ab = $acceptLanguage->getBasePart();
        $pb = $priority->getBasePart();
        $as = $acceptLanguage->getSubPart();
        $ps = $priority->getSubPart();
        $baseEqual = !strcasecmp($ab, $pb);
        $subEqual = !strcasecmp($as, $ps);
        if (($ab == '*' || $baseEqual) && ($as === null || $subEqual)) {
            $score = 10 * $baseEqual + $subEqual;
            return new Match($acceptLanguage->getQuality() * $priority->getQuality(), $score, $index);
        }
        return null;
    }