When\When::createDaysList PHP Method

    protected static function createDaysList($days)
    {
        $_days = array();
        foreach ($days as $day) {
            $day = ltrim($day, "+");
            $day = trim($day);
            $ordwk = 0;
            $weekday = false;
            if (strlen($day) === 2) {
                $weekday = $day;
            } else {
                list($ordwk, $weekday) = sscanf($day, "%d%s");
            }
            $_days[] = $ordwk . strtolower($weekday);
        }
        return $_days;
    }