Object references... i simply don't understand it at all ;)

Hello!

I can't see any difference between:

$MyObject = new Object();
and
$MyObject =& new Object();

I used to think that if I use =&, I will be able to change variables of
the class and each new object created after that from the modified class
will have new, modified variables - but that seems not to be true...

I use PHP5 - is it the problem?

"kajaman (a.k.a. Hubert Å�ÄTpicki ;))" <hubert5@wp.pl> wrote in message
news:cfadvk$nkg$1@nemesis.news.tpi.pl...
> $MyObject = new Object();
> and
> $MyObject =& new Object();
>
> I used to think that if I use =&, I will be able to change variables of
> the class and each new object created after that from the modified class
> will have new, modified variables - but that seems not to be true...

no if you add:

$AnotherMyObject = & $MyObject;

than changing $AnotherObject will also change $MyObject and other way
around.

rush
--

http://www.templatetamer.com/

rush wrote:
>
> $AnotherMyObject = & $MyObject;
>
> than changing $AnotherObject will also change $MyObject and other way
> around.

Yes! And I understand it! But... Why people use:
$MyObject =& new Object
while it seems to work exacly the same as:
$MyObject = new Object...
strange :-/

kajaman (a.k.a. Hubert ??picki ;)) schrieb:

> Yes! And I understand it! But... Why people use:
> $MyObject =& new Object
> while it seems to work exacly the same as:
> $MyObject = new Object...

It's the same in PHP5.

In PHP4 it is different:

$MyObject = &new Object;
creates a new instance and $MyObject get's a reference to it.

$MyObject = new Object;
creates a new instance and copies it to $MyObject.

Regards,
Matthias

kajaman (a.k.a. Hubert �ępicki ;)) wrote:

> rush wrote:
>
>>
>> $AnotherMyObject = & $MyObject;
>>
>> than changing $AnotherObject will also change $MyObject and other way
>> around.
>
>
> Yes! And I understand it! But... Why people use:
> $MyObject =& new Object

PHP4: creates a new Object then points $MyObject at it

> while it seems to work exacly the same as:
> $MyObject = new Object...

PHP4: creates a new Object then copies the contents of same into
$MyObject (MyObject is a copy)

In practical terms you end up with the same result. However you have a
spare object floating around to be cleaned up by the garbage collector.

Kevin Thorpe wrote:
> kajaman (a.k.a. Hubert �ępicki ;)) wrote:
>
>> rush wrote:
>>
>>>
>>> $AnotherMyObject = & $MyObject;
>>>
>>> than changing $AnotherObject will also change $MyObject and other way
>>> around.
>>
>>
>>
>> Yes! And I understand it! But... Why people use:
>> $MyObject =& new Object
>
>
> PHP4: creates a new Object then points $MyObject at it
>
>> while it seems to work exacly the same as:
>> $MyObject = new Object...
>
>
> PHP4: creates a new Object then copies the contents of same into
> $MyObject (MyObject is a copy)
>
> In practical terms you end up with the same result. However you have a
> spare object floating around to be cleaned up by the garbage collector.
Thank you very much, now I see it clear :).

.oO(kajaman (a.k.a. Hubert ??picki ;)))

>Yes! And I understand it! But... Why people use:
>$MyObject =& new Object
>while it seems to work exacly the same as:
>$MyObject = new Object...

Only in PHP5, it uses references by default. In PHP4 it's a difference.

Micha