template

    template <typename T> QByteArray listToArray(const QList<T>& list) {
        QByteArray out;
        QDataStream stream(&out, QIODevice::WriteOnly);
        for (const T& t : list) {
            stream << t;
        }
        return out;
    }
    template <typename T> template <> QByteArray listToArray<QList<T>>(const QList<T>& list) {
        QByteArray out;
        QDataStream stream(&out, QIODevice::WriteOnly);
        for (const T& t : list) {
            stream << listToArray(t);
        }
        return out;
    }