Someone

  public function prep(&$data, $flatten = self::PREP_HOP) {    foreach($data as &$v) {        $v = (is_array($v))		  ? (($flatten & self::PREP_JOIN) 		    ? join(',', prep($v)) 			  : prep($v))		    : $v = "'" . $v . "'";    }      return $data;  }