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Posted by Jerry Stuckle on 12/27/07 14:40
Steve wrote:
> "Michael Fesser" <netizen@gmx.de> wrote in message
> news:0hlim3hgb5p7ifm2o13pjm6q4l0q5jhiim@4ax.com...
>> .oO(Logos)
>>
>>> On Dec 13, 3:16 pm, Michael Fesser <neti...@gmx.de> wrote:
>>>
>>>> At least when working with objects. But nevertheless
>>>>
>>>> $foo = new Test();
>>>> $a = $foo;
>>>> $b = &$foo;
>>>>
>>>> are still different things, even in PHP 5. In some particular situations
>>>> this might become an issue.
>>> Oooo...errr...ummm...could someone explain how exactly those are
>>> different when using PHP5, then, please? If everything is done by
>>> reference for objects, then to me $a and $b both look like pointers to
>>> an object.
>> Don't confuse pointers with references, they are entirely different
>> things. PHP doesn't know pointers.
>>
>> And correctly spoken objects in PHP 5 are _not_ passed by reference (at
>> least it's not what PHP calls a reference), even if it's still mentioned
>> that way on many websites. But it's wrong.
>>
>> Internally objects are represented by a handle (a simple number), which
>> is what is moved around when you assign objects to variables, copy them
>> or pass them to a function. You're never working directly with the
>> object itself, but with its handle. Of course usually you won't notice
>> that, because it's handled transparently by PHP.
>
> michael, for people who come from a c/c++ background, what you've described
> is *exactly* a pointer. the only difference in php is that rather than the
> handle pointing to a memory address where information is stored, this php
> handle points to a symbol table entry where information is stored.
>
Wrong again, Stevie. A C++ pointer is not the same as a C++ reference.
And C doesn't have references, just as PHP doesn't have pointers.
> in php, a reference (or byref) behaves *IDENTICALLY* to a c/c++ pointer.
> there are somethings that you cannot do with this reference in php that you
> could in other languages, however, the nature of the beast is the same. i
> know that a reference in php is really just an alias of the symbol table
> entry, but really that just seems a matter of symantics to me. i don't care
> where things are stored at such a low level when i'm writing in a scripting
> language. i care about behaviors.
>
Wrong again. They behave much differently.
--
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Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
jstucklex@attglobal.net
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