public static function indexes($text)
{
    $el = Html::el();
    foreach (Nette\Utils\Strings::split($text, '~((?:\^2)|(?:\^3))~', PREG_SPLIT_OFFSET_CAPTURE) as $part) {
        $el->add($part[0] == '^'
                ? Html::el('sup')->setText(substr($part, 1))
                : Html::el()->setText($part)
            );
    }
    return $el;
}