public static function stringToArray(string $string): array
    {
        list($from, $to) = explode(self::SEPARATOR, $string);
        $from = empty($from)
            ? self::ZERO
            : (is_numeric($from)
                ? (int) $from
                : $from);

        $to = empty($to)
            ? self::INFINITE
            : (is_numeric($to)
                ? (int) $to
                : $to);

        return [$from, $to];
    }