note 109378 added to functions.returning-values

I used recursive to reverse a string, created code as below <?php $str="abcdef"; function convert($str) { static $retStr; if ($str==NULL || $str=="") { return $retStr; // here the $retStr="fedcba", correct } else { $retStr .= substr($str, -1); $str = substr($str, 0, -1); convert($str); } } echo "\nThe return string = ".convert($str)."\n"; // the return string is empty ?> if I changed the code, use global, like below <?php $str="abcdef"; $retStr = ""; function convert($str) { global $retStr; if ($str==NULL || $str=="") { return NULL; } else { $retStr .= substr($str, -1); $str = substr($str, 0, -1); convert($str); } } convert($str); echo "\nThe global = ".$retStr; // get the right result "fedcba" ?> ---- Server IP: 69.147.83.197 Probable Submitter: 72.83.147.9 ---- Manual Page -- http://www.php.net/manual/en/functions.returning-values.php Edit -- https://master.php.net/note/edit/109378 Del: integrated -- https://master.php.net/note/delete/109378/integrated Del: useless -- https://master.php.net/note/delete/109378/useless Del: bad code -- https://master.php.net/note/delete/109378/bad+code Del: spam -- https://master.php.net/note/delete/109378/spam Del: non-english -- https://master.php.net/note/delete/109378/non-english Del: in docs -- https://master.php.net/note/delete/109378/in+docs Del: other reasons-- https://master.php.net/note/delete/109378 Reject -- https://master.php.net/note/reject/109378 Search -- https://master.php.net/manage/user-notes.php