Doc #76387 [Com]: Different behavior between Array and ArrayIterator in foreach loop...
Edit report at https://bugs.php.net/bug.php?id=76387&edit=1
ID: 76387
Comment by: a at b dot c dot de
Reported by: Evgeny dot Mazanik at gmail dot com
Summary: Different behavior between Array and ArrayIterator
in foreach loop...
Status: Open
Type: Documentation Problem
Package: SPL related
Operating System: Windows 10
PHP Version: 7.2.6
Block user comment: N
Private report: N
New Comment:
For what it's worth, of course, I'll point out that this is the same difference in
behaviour as when arrays vs. ArrayObjects are passed as arguments to functions. The array and the
ArrayObject are both passed by value; in the array's case is the sequence of key/value pairs it
is made up of; the ArrayObject's value is the ArrayObject itself.
In the same wise, the foreach() iterates over the value it is given to iterate over. That value
isn't replaced while the loop is iterating. Changing the contents of an array changes its value
(but the foreach doesn't see that - it's iterating over the value it was given). But
changing the contents of an ArrayObject doesn't change its value - it's still the same
ArrayObject, and its value is still the one given to the foreach).
<?
$foo = ['a','b']; // The value of $foo is the sequence 0=>'a',
1=>'b'
// $foo = new ArrayIterator(['a']); // The value of $foo is an ArrayIterator object.
foreach($foo as $b)
{
echo $b;
$foo[] = 'f'; // Append to $foo
}
echo "\n",count($foo),"\t",join($foo);
?>
Bug #75173 addressed an instance of the opposite problem to the current happening: the value of the
Iterator object is the Iterator object, so the loop should have been iterating over that
Iterator's elements.
Previous Comments:
------------------------------------------------------------------------
[2018-05-29 07:55:15] Evgeny dot Mazanik at gmail dot com
Description:
------------
---
From manual page: http://www.php.net/arrayiterator.offsetunset
---
Different behavior when using Array and ArrayIterator in a foreach loop when using unset () for an
associative array.
1. When using an Array in a loop and removing an element in the body of the loop, the loop is
executed across all elements of the array.
2. When using ArrayIterator in a loop and deleting an element in the body of the loop, the loop is
NOT performed on all elements of the array.
PS:
A similar problem:
https://bugs.php.net/bug.php?id=75173&edit=2
Test script:
---------------
http://sandbox.onlinephpfunctions.com/code/ff65bf3858b153780b588476ebaa77b0aba7b4db
Actual also for PHP 7.2.4, 7.2.6
Expected result:
----------------
Probably:
Via array:
item1
item2
item3
Via ArrayIterator:
item1
item2
item3
Actual result:
--------------
Via array:
item1
item2
item3
Via ArrayIterator:
item1
item3
------------------------------------------------------------------------
--
Edit this bug report at https://bugs.php.net/bug.php?id=76387&edit=1
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