Everything

php

clone wars

php.internals

Unnamed Person

22 years ago

It appears that cloning is broken, since a modification to the clone
modifies the original. For my __clone method implementation, I allow
all of the variables to be set by default except for one. But this
problem persists even when I don't modify that one variable.

Unnamed Person

22 years ago

I forgot to mention: I am use b4

On 15 Feb 2004, at 5:45 PM, Herr Witten wrote:

Marcus Börger

22 years ago

Hello,

most probably that property is a reference in which case the result is
correct.

Sunday, February 15, 2004, 11:45:56 PM, you wrote:

> It appears that cloning is broken, since a modification to the clone
> modifies the original. For my __clone method implementation, I allow
> all of the variables to be set by default except for one. But this
> problem persists even when I don't modify that one variable.

--
Best regards,
Marcus                            mailto:helly@php.net

Unnamed Person

22 years ago

It appears that only one of the variables, an array, is being shared
across these multiple objects, but other array variables are not.
Moreover, When I make a clone and then set the clone to null, all
clones made thereafter are correct.

$clone = clone $object;
$clone = null;

Also, I can't replicate the problem with another class. It only seems
to be this class.

On 15 Feb 2004, at 5:47 PM, Marcus Boerger wrote:

Unnamed Person

22 years ago

More specifically,

This causes a change in $object:

$clone = clone $object;
$clone->troublesomeVariable = array();

But this doesn't:

$clone = clone $cell;
$clone = null;
$clone->_subElements = array();

On 15 Feb 2004, at 7:35 PM, Herr Witten wrote:

Unnamed Person

22 years ago

That should be clone $object for the example.

On 15 Feb 2004, at 7:39 PM, Herr Witten wrote:

Marcus Börger

22 years ago

Hello,

first as i said do the following to verify:
marcus@frodo /usr/src/php5 $ php -r '$a=array(1,2);class t{public $a;function f(){$this->a=&$GLOBALS["a"];}}$o1=new t;$o1->f();var_dump($o1);$o2=clone $o1;$o1->a=2;var_dump($o2);var_dump($o1);'
make: `sapi/cli/php' is up to date.
object(t)#1 (1) {
["a"]=>
&array(2) {
[0]=>
int(1)
[1]=>
int(2)
}
}
object(t)#2 (1) {
["a"]=>
&int(2)
}
object(t)#1 (1) {
["a"]=>
&int(2)
}
then remove the '&'.

second read the docs and question such things on general@php.net.

Monday, February 16, 2004, 1:39:44 AM, you wrote:

> More specifically,

> This causes a change in $object:

> $clone = clone $object;
> $clone->troublesomeVariable = array();

> But this doesn't:

> $clone = clone $cell;
> $clone = null;
> $clone->_subElements = array();

> On 15 Feb 2004, at 7:35 PM, Herr Witten wrote:

>> It appears that only one of the variables, an array, is being shared
>> across these multiple objects, but other array variables are not.
>> Moreover, When I make a clone and then set the clone to null, all
>> clones made thereafter are correct.
>>
>> $clone = clone $object;
>> $clone = null;
>>
>> Also, I can't replicate the problem with another class. It only seems
>> to be this class.
>>
>> On 15 Feb 2004, at 5:47 PM, Marcus Boerger wrote:
>>
>>> Hello,
>>>
>>> most probably that property is a reference in which case the result is
>>> correct.
>>>
>>> Sunday, February 15, 2004, 11:45:56 PM, you wrote:
>>>
>>>> It appears that cloning is broken, since a modification to the clone
>>>> modifies the original. For my __clone method implementation, I allow
>>>> all of the variables to be set by default except for one. But this
>>>> problem persists even when I don't modify that one variable.
>>>
>>>
>>>
>>>
>>> --
>>> Best regards,
>>>  Marcus                            mailto:helly@php.net
>>>
>>
>> --
>> PHP Internals - PHP Runtime Development Mailing List
>> To unsubscribe, visit: http://www.php.net/unsub.php
>>

--
Best regards,
Marcus                            mailto:helly@php.net

Unnamed Person

22 years ago

> first as i said do the following to verify:

It's a nice example, but it doesn't apply. I don't make a reference.

> second read the docs and question such things on general@php.net.

I did. This problem seemed to be internal, and it still does.

Marcus Börger

22 years ago

Hello,

Monday, February 16, 2004, 1:54:36 AM, you wrote:

>> first as i said do the following to verify:

> It's a nice example, but it doesn't apply. I don't make a reference.

>> second read the docs and question such things on general@php.net.

> I did. This problem seemed to be internal, and it still does.

Ok, so you are sure var_dump() doesn't show the & for the property in
question? If so i would need to know where exactly the array comes from.
And the best way to proceed tehn is to create a bug report with a short
reproducing script.

--
Best regards,
Marcus                            mailto:helly@php.net

Unnamed Person

22 years ago

Here, I have reproduced the problem:

class A
{
var $a = array();

public function makeAReference()
{
$array = $this->getA();
}

public function &getA()
{
return $this->a;
}
}

$A = new A;
$A->a = array(1);
$A->makeAReference();
$clone = clone $A;
$clone->a = array();

print_r($A);

Try it with an without $A->makeAReference()

I sent in a report. Thanks.

On 15 Feb 2004, at 8:04 PM, Marcus Boerger wrote:

Unnamed Person

22 years ago

This too:

class A
{
var $a = array();

public function &getA()
{
return $this->a;
}
}

$A = new A;
$A->a = array(1);
$array = &$A->getA();
$clone = clone $A;
$clone->a = array();

print_r($A);

On 15 Feb 2004, at 9:14 PM, Herr Witten wrote:

Unnamed Person

22 years ago

This was never resolved:

Is this, or is this not a bug:

class A
{
var $a;
}

$A = new A;
$A->a = array(1);
$array = &$A->a;
$clone = clone $A;
$clone->a = array(); //Affects a in $A.

print_r($A);