note 125350 deleted from functions.user-defined by cmb
| From: | cmb@php.net | Date: | Fri, 11 Sep 2020 14:04:05 +0000 |
| Subject: | note 125350 deleted from functions.user-defined by cmb | ||
| References: | 1 | Groups: | php.notes |
| Request: | Send a blank email to php-notes+get-215099@lists.php.net to get a copy of this message | ||
Note Submitter: greenbluemoonlight at gmail dot com
----
Notice that recursion($a+1) has the same output as ++a.
If recursion($a++) is mistakenly used instead of recursion(++$a),
The output is infinite loop.
<?php
////recursion($a + 1)
function recursion($a)
{
if ($a < 4) {
echo $a . "\n";
recursion($a + 1);
}
}
recursion(1);
//Outputs:
1
2
3
////recursion(++$a)
function recursion($a)
{
if ($a < 4) {
echo $a . "\n";
recursion(++$a);
}
}
recursion(1);
//Outputs:
1
2
3
////recursion($a++)
function recursion($a)
{
if ($a < 4) {
echo $a . "\n";
recursion($a++);
}
}
recursion(1);
//Outputs: INFINITE LOOP !!!
1
1
1
1
1..............
?>