public static function merge(...$options) {
            $o = [];

            foreach ($options as $opt) {
                if ($opt instanceof Options) {
                    $o = array_merge($o, $opt->toArray());
                } elseif (is_array($opt)) {
                    $o = array_merge($o, $opt);
                }
            }

            return new self(Util::trimNulls($o));
        }