#24118 [Ana->Csd]: Error while using foreach
| From: | vrana@php.net | Date: | Sat, 07 Aug 2004 10:05:17 +0000 |
| Subject: | #24118 [Ana->Csd]: Error while using foreach | ||
| References: | 1 | Groups: | php.doc |
| Request: | Send a blank email to phpdoc+get-969362829@lists.php.net to get a copy of this message | ||
ID: 24118
Updated by: vrana@php.net
Reported By: young at sl dot com dot ua
-Status: Analyzed
+Status: Closed
Bug Type: Documentation problem
Operating System: *
PHP Version: Irrelevant
New Comment:
This bug has been fixed in the documentation's XML sources. Since the
online and downloadable versions of the documentation need some time
to get updated, we would like to ask you to be a bit patient.
Thank you for the report, and for helping us make our documentation
better.
Note: "If you assign a value to variable with references in the foreach
statement, references are modified too." + example:
<?php
$ref = 0;
$row =& $ref;
foreach (array(1, 2, 3) as $row) {
// do something
}
echo $ref; // 3 - last element of the iterated array
?>
Previous Comments:
------------------------------------------------------------------------
[2003-06-11 05:22:25] sniper@php.net
Make this a documentation problem..I couldn't find this explanation
there. :)
------------------------------------------------------------------------
[2003-06-11 02:59:27] zeev@php.net
Thank you for taking the time to write to us, but this is not
a bug. Please double-check the documentation available at
http://www.php.net/manual/ and the instructions on how to
report
a bug at http://bugs.php.net/how-to-report.php
Taking the reproducible example:
<?php
$arr = array(1, 2, 3, 4, 5);
$sizeOf = sizeof($arr);
for ($i = 0; $i < $sizeOf; $i++) {
$row =& $arr[$i];
$row = $row * $row;
}
foreach ($arr as $row) {
echo $row."<br>";
}
?>
You shouldn't be using the reference variable that you used previously
in the foreach loop, since every iteration will assign the value to
both $row, and any other references it's attached to, in this case,
$arr[4]. This is why you get the last iterated value ($arr[3]) in
$arr[4], when you get to it.
------------------------------------------------------------------------
[2003-06-10 18:15:29] elmicha@php.net
Yes; more evidence:
<?php
$arr = array(1, 2, 3, 4, 5);
$sizeOf = sizeof($arr);
for ($i = 0; $i < $sizeOf; $i++) {
$row = &$arr[$i];
}
foreach ($arr as $row) {
echo $row."<br>";
}
?>
Output: 1<br>2<br>3<br>4<br>4<br>
<?php
$arr = array(1, 2, 3, 4, 5);
$sizeOf = sizeof($arr);
for ($i = 0; $i < $sizeOf; $i++) {
$row = &$arr[$i];
}
foreach ($arr as $x) {
echo $x."<br>";
}
?>
Output: 1<br>2<br>3<br>4<br>5<br>
------------------------------------------------------------------------
[2003-06-10 17:56:08] sniper@php.net
Zeev, here is first one I verified with both 4.3.3-dev and 5.0.0-dev.
Have fun fixing this one. :)
------------------------------------------------------------------------
[2003-06-10 17:32:00] young at sl dot com dot ua
Sample code to make this bug:
<?php
$arr = array(1, 2, 3, 4, 5);
$sizeOf = sizeof($arr);
for ($i = 0; $i < $sizeOf; $i++) {
$row =& $arr[$i];
$row = $row * $row;
}
foreach ($arr as $row) {
echo $row."<br>";
}
?>
Return
1
4
9
16
16
------------------------------------------------------------------------
The remainder of the comments for this report are too long. To view
the rest of the comments, please view the bug report online at
http://bugs.php.net/24118
--
Edit this bug report at http://bugs.php.net/?id=24118&edit=1