$re = '/^(((\d+,)+\d+|((\d+|[*])[/]\d+|((JAN|FEB|APR|MA[RY]|JU[LN]|AUG|SEP|OCT|NOV|DEC)(-(JAN|FEB|APR|MA[RY]|JU[LN]|AUG|SEP|OCT|NOV|DEC))?))|(\d+-\d+)|\d+(-\d+)?[/]\d+(-\d+)?|\d+|[*]|(MON|TUE|WED|THU|FRI|SAT|SUN)(-(MON|TUE|WED|THU|FRI|SAT|SUN))?) ?){5}$/idu';
$str = '';
preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php