pharext\License::mergeLicensePattern PHP Method

    private function mergeLicensePattern($upper, $lower)
    {
        $pattern = "";
        $length = strlen($upper);
        for ($i = 0; $i < $length; ++$i) {
            if ($lower[$i] === $upper[$i]) {
                $pattern .= $upper[$i];
            } else {
                $pattern .= "[" . $upper[$i] . $lower[$i] . "]";
            }
        }
        return $pattern;
    }