Bug #51409 [Opn->Bgs]: foreach structure pass by reference scope issue
| From: | rasmus@php.net | Date: | Fri, 26 Mar 2010 21:36:26 +0000 |
| Subject: | Bug #51409 [Opn->Bgs]: foreach structure pass by reference scope issue | ||
| References: | 1 | Groups: | php.bugs |
| Request: | Send a blank email to php-bugs+get-149089@lists.php.net to get a copy of this message | ||
Edit report at http://bugs.php.net/bug.php?id=51409&edit=1
ID: 51409
Updated by: rasmus@php.net
Reported by: sramage at nucleuslabs dot com
Summary: foreach structure pass by reference scope issue
-Status: Open
+Status: Bogus
Type: Bug
Package: Arrays related
Operating System: FREEBSD 8.0
PHP Version: 5.2.13
New Comment:
This makes perfect sense. After your first foreach loop, $banana is a
reference
to the last element in your $bananas array. Anything you do to that
$banana
variable is going to affect that last element. So, in your coconut
foreach, you
are now asking PHP to assign the first element of the coconut array to
the last
element of your bananas array which is exactly the output you are
getting. No
bug here.
Previous Comments:
------------------------------------------------------------------------
[2010-03-26 22:31:41] sramage at nucleuslabs dot com
Description:
------------
When an ampersand operator is used in a foreach language construct The
pass by reference variable causes *copies* of the parent array used in
the foreach loop to be modified in any future use of the initial pass by
reference variable.
This is very hard to explain clearly but see the test script below for
clarification it is a very simple test script.'
Similar bugs like this have been reported and documentation outlines a
simple workaround that does work and solves my problem.
but I figured I would report this problem as *copies* of the array are
affected and it seems kind of strange.
Test script:
---------------
class Monkey{
public $bananas=array();
public function AddBananas($bananas){
$this->bananas=$bananas;
}}
$bananas=array();
$bananas['banana1']=array('color'=>'yellow','size'=>'big');
$bananas['banana2']=array('color'=>'green','size'=>'small');
$coconuts=array();
$coconuts['coconut1']['size']='tiny';
$coconuts['coconut2']['size']="I'm a";
$monkey=new Monkey();
foreach($bananas as $key=>&$banana){
$banana['id']=$key+1;
}
$monkey->AddBananas($bananas);
foreach($coconuts as $banana){
$banana['type']="coconut!";
}
print_r($monkey->bananas);
Expected result:
----------------
Array
(
[banana1] => Array
(
[color] => yellow
[size] => big
[id] => 1
)
[banana2] => Array
(
[color] => green
[size] => small
[id] => 2
)
)
Actual result:
--------------
Array
(
[banana1] => Array
(
[color] => yellow
[size] => big
[id] => 1
)
[banana2] => Array
(
[size] => I'm a
[type] => coconut!
)
)
------------------------------------------------------------------------
--
Edit this bug report at http://bugs.php.net/bug.php?id=51409&edit=1