Bug #54189 [Com]: foreach changes array values after iterating by reference followed by foreach
Edit report at https://bugs.php.net/bug.php?id=54189&edit=1
ID: 54189
Comment by: chealer at gmail dot com
Reported by: phazei at gmail dot com
Summary: foreach changes array values after iterating by
reference followed by foreach
Status: Not a bug
Type: Bug
Package: Scripting Engine problem
Operating System: RHEL 5.6
PHP Version: 5.2.17
Block user comment: N
Private report: N
New Comment:
The problematic behavior behind this issue is being tracked in #62132.
Previous Comments:
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[2011-03-08 09:24:34] scottmac@php.net
This is on the foreach manual page.
Between the two foreach loops, $value is a reference to the last entry in the
array.
When the second loop starts you then start assigning new values to $value which
reference the last element of the array.
------------------------------------------------------------------------
[2011-03-08 08:11:41] phazei at gmail dot com
Description:
------------
(I searched through the bug reports and found some foreach pointer issues, but
none related to this)
If I simply go through an array with a referenced value like so:
foreach ($array as &$value) { }
And then go through it again, not referenced, like so:
foreach ($array as $value) { }
Both times using the same variable $value, then during the second foreach, the
second to the last value is actually copied over the last value changing the
array.
If I simply use $value2 there is no issue.
Test script:
---------------
$array =
array('aaaaa','bbbbb','ccccc','ddddd','eeeee');
echo '1) '.print_r($array, true).'<br>';
foreach ($array as &$value) { }
echo '2) '.print_r($array, true).'<br> 3) ';
foreach ($array as $key => $value) { echo "[$key] => $value "; }
echo '<br> 4) '.print_r($array, true).'<br>';
Expected result:
----------------
1) Array ( [0] => aaaaa [1] => bbbbb [2] => ccccc [3] => ddddd [4] => eeeee )
2) Array ( [0] => aaaaa [1] => bbbbb [2] => ccccc [3] => ddddd [4] => eeeee )
3) [0] => aaaaa [1] => bbbbb [2] => ccccc [3] => ddddd [4] => eeeee
4) Array ( [0] => aaaaa [1] => bbbbb [2] => ccccc [3] => ddddd [4] => eeeee )
Actual result:
--------------
1) Array ( [0] => aaaaa [1] => bbbbb [2] => ccccc [3] => ddddd [4] => eeeee )
2) Array ( [0] => aaaaa [1] => bbbbb [2] => ccccc [3] => ddddd [4] => eeeee )
3) [0] => aaaaa [1] => bbbbb [2] => ccccc [3] => ddddd [4] => ddddd
4) Array ( [0] => aaaaa [1] => bbbbb [2] => ccccc [3] => ddddd [4] => ddddd )
------------------------------------------------------------------------
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Edit this bug report at https://bugs.php.net/bug.php?id=54189&edit=1
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