Nette\Forms\Helpers::prepareAttrs PHP Метод

    private static function prepareAttrs($attrs, $name)
    {
        $dynamic = [];
        foreach ((array) $attrs as $k => $v) {
            $p = str_split($k, strlen($k) - 1);
            if ($p[1] === '?' || $p[1] === ':') {
                unset($attrs[$k], $attrs[$p[0]]);
                if ($p[1] === '?') {
                    $dynamic[$p[0]] = array_fill_keys((array) $v, TRUE);
                } elseif (is_array($v) && $v) {
                    $dynamic[$p[0]] = $v;
                } else {
                    $attrs[$p[0]] = $v;
                }
            }
        }
        return [$dynamic, '<' . $name . Html::el(NULL, $attrs)->attributes()];
    }