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Date: Fri, 28 Nov 2014 14:08:18 +0000
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Subject: Re: [PHP-DEV] New function: spl_object_id() or spl_object_handle()
From: rowan.collins@gmail.com (Rowan Collins)

Ferenc Kovacs wrote on 28/11/2014 13:51:
> On Fri, Nov 28, 2014 at 2:14 PM, Sebastian Krebs <krebs.seb@gmail.com>
> wrote:
>
>> 2014-11-28 2:13 GMT+01:00 Bostjan Skufca <bostjan@a2o.si>:
>>
>>> Hello everyone,
>>>
>>> this is a proposal to add new function to PHP core: spl_object_id()
>>>
>>>
>>> The story:
>>> ========
>>> Recently I was debugging some larger libraries and sorely missed a
>> function
>>> that would return an object ID. A function called spl_object_hash()
>> exists,
>>> but it returns identical hashes for equal objects.
>>
>> It returns unique IDs for existing objects. A hash is only reused only when
>> the corresponding object was removed by the GC earlier.
>> So actually asking me it makes more sense to "fix" the behaviour of
>> spl_object_hash(),
>>
> yeah, the more I think about it the more I feel that the current
> implementation is just a landmine.

Is there any BC implication of changing the implementation? Or is it 
just that we don't know what the alternative should be?

Looking at the implementation of spl_object_hash() [1] it already uses 
Z_OBJ_HANDLE_P(obj) as part of the output, so presumably that isn't 
enough to guarantee uniqueness anyway? (Which then leads to the question 
of what the advantage of an spl_object_id() function would actually be, 
if it's *less* unique than spl_object_hash())

[1] http://lxr.php.net/xref/PHP_TRUNK/ext/spl/php_spl.c#756
-- 
Rowan Collins
[IMSoP]