Re: [PHP-DEV] toString() and Object #ID
Do you think there's an easy and clean approaching to solve this kind of problem? Or maybe the problem should be solved on array_diff() and other functions to make them not try to cast the object as a string to compare? If use array_udiff with a comparison function that compares the spl_object_hash of the two operands, you should have your old behavior back. David -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
Hello Pavel,
I still fail to understand why spl_object_hash() does not work for you.
How about:
function foo($obj) {
if (is_object($obj)) {
return object( . get_class($obj) . )# . spl_object_hash($obj);
}
return NULL;
}
marcus
Sunday, July 1, 2007, 9:18:19 PM, you wrote:
Again see mail archive for why. That said the name appears to be
the best option already.
Oh, yes, you're right spl_object_hash does its job and does it very
well, there's really no point rename it(or make an alias) into
object_get_id. I should have stated more clear what I think
object_get_id could actually be.
How about object_get_id being a function returning the very first line
of var_dump's output being applied to the object? Let me be a bit more
specific, here's an example of var_dump usage:
$ php -r class Foo{};$foo = new Foo();var_dump($foo);
object(Foo)#1 (0) {
}
What I actually need, not the object hash but simply its unique id.
And in this case object(Foo)#1 would be just fine. How can I get it?
The only way AFAIK is to surround var_dump with
ob_start/ob_get_contents/ob_end_clean functions and extract this
value.
The problem with approach is if one has a complex object connected
with a graph of other complex objects(with recursive links) var_dump
may take a _very_ long time to complete.
And this is what object_get_id could do - simply return object id
prefixed with the class name.
Best regards,
Marcus
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Re: [PHP-DEV] toString() and Object #ID
Hello Bruno, the documentation says array_diff() uses explicit string casting. Maybe it is time to fix this to object comparision. But then what about mixed arrays? In my opinion it was broken before and you just got lucky with using a debug feature without even knowing. Now the current PHP version at least offers you to do it correctly. Speaking of the mentioned PEAR issue. Now what is your string representation there? Was it actually correct? Was it intended that you were simply comparing class name and handle? Or were you actually expecting to compare the data? Honestly i would expect to compare by elements, say you fetch from a person database into two arrays that are modified differently using php code. Now i'd like to do the test based on the elements, say the ones from the persons.name column. And it does not matter what the different object IDs arebecasue two fetch operations would result in two different IDs even if theay are referring to the same data row. So in this case you apperently do not want to use array_diff() at all. You want to use array_udiff_*(). In the end object to string conversion other than something that leads to a text that can be used on a html or txt file pretty much sounds like a design flaw. marcus Monday, July 30, 2007, 9:30:12 PM, you wrote: On 7/30/07, Marcus Boerger [EMAIL PROTECTED] wrote: Hello Pavel, I still fail to understand why spl_object_hash() does not work for you. Hello. Just as a side note, this broke a few things for me. For example, in an application, I have 2 arrays of objects, and I try to call array_diff() on them. Before PHP 5.2, it would work, possibly because array_diff() would cast the objects as strings, and then compare them (if I understood the problem correctly). Now, this doesn't work anymore, because the object can't be cast to string by default. Of course, I could add a __toString() method to the objects and return something there, but problem is, all objects are extended from a base class from PEAR (it's DB_DataObject), and it wouldn't be a Good Thing to modify the PEAR class directly (updates would break). So, I got kind of stuck, and tried to add the __toString() dynamically to the objects in question using the runkit PECL package, but although it adds the method correctly, PHP doesn't recognize it as a magic method, and won't call it when needed (filed bug #11691 on PECL for it). Do you think there's an easy and clean approaching to solve this kind of problem? Or maybe the problem should be solved on array_diff() and other functions to make them not try to cast the object as a string to compare? Thanks -- Bruno Lustosa [EMAIL PROTECTED] ZCE - Zend Certified Engineer - PHP! http://www.lustosa.net/ Best regards, Marcus -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
Hello all, and thanks Stas for the explanations. Monday, July 2, 2007, 7:52:03 PM, you wrote: We could add a counter that gets incremented for each object that is created and associate that number with the object. Wouldn't that solve the problem (if there is one)? It would solve it, but it would require modifying each extension dealing with objects in order to register all objects in this global registry and of course it would require adding another value into object structure. I'm not sure having running numeric ID is that important. If you just need to know if two variables are the same object, you have ===. If you need to index by it, you have the hash. Exactly. And the index should not be dependant on the contents of the properties. Also you should always use the shortest unique ID. In our case as very well explained it is handler plus id. What we could do to prevent two different objects getting the same hash is to ask for the memory locationbut the we cannot use the zval container as multiple zval containers might point to the same object. Nor can we really use the object location in its object storage as we do not know if that is safe. Thus we could only add an independent counter which imo is pretty bad and as epxplained it would created overly complex overhead. Now what you actually want with the hash is indexing. That probably means storing the object in whatever holds the index - maybe an array. Maybe something else. Either way no other object can get the same hash as the object is stored and thus no other objetc can get the same handler,id combo at the same time. So i do not see any issue here. If you guys want it more complex i suggest you extend the hash in userland and add a special property/interface solution. Best regards, Marcus -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
Hi Pavel,
Pavel Shevaev wrote:
Folks, is this really wanted behavior? Because if so, why does the
following result in the same hash as well(PHP-5.2.1)?
$ php -r class Foo{};$foo = new
Foo();var_dump(spl_object_hash($foo));$foo-bar =
1;var_dump(spl_object_hash($foo));
string(32) d1f40a1cc04d8c79d09ae6262666adbb
string(32) d1f40a1cc04d8c79d09ae6262666adbb
Because you calculate the hash for the same object. It does not matter,
that you changed a property, the $foo is still the same object.
Best regards,
Stephan
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Re: [PHP-DEV] toString() and Object #ID
On Sun, July 1, 2007 2:18 pm, Pavel Shevaev wrote:
$ php -r class Foo{};$foo = new Foo();var_dump($foo);
object(Foo)#1 (0) {
}
What I actually need, not the object hash but simply its unique id.
According to Marcus, it's NOT unique.
But I can see that for debugging, it would be very very very useful to
have a correctly named function which returns this number, whatever it
is, even if it's not an ID.
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Re: [PHP-DEV] toString() and Object #ID
On Sun, July 1, 2007 2:50 pm, Sebastian Bergmann wrote: Pavel Shevaev schrieb: What I actually need, not the object hash but simply its unique id. The problem is that there is no such unique id in the current engine. How does PHP internally distinguish it? Surely it has some kind of pointer/address thingie... I don't think a developer CARES what the ID is (or isn't) or what it looks like, so long as it's reasonably short and fast to access, and it's not something that's only available sometimes on some systems. -- Some people have a gift link here. Know what I want? I want you to buy a CD from some indie artist. http://cdbaby.com/browse/from/lynch Yeah, I get a buck. So? -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
Am 01.07.2007 um 21:18 schrieb Pavel Shevaev: Again see mail archive for why. That said the name appears to be the best option already. Oh, yes, you're right spl_object_hash does its job and does it very well, there's really no point rename it(or make an alias) into object_get_id. I should have stated more clear what I think object_get_id could actually be. Not quite. It creates a hash of an object, so two objects with the same data yield the same hashes: var_dump(spl_object_hash(new stdClass()), spl_object_hash(new stdClass ())); - David -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
Not quite. It creates a hash of an object, so two objects with the same data yield the same hashes: var_dump(spl_object_hash(new stdClass()), spl_object_hash(new stdClass())); I don't believe that it's data dependent. Rather in your example the same memory-space is used for those two objects because they don't exist in parallel. The first is cleared before the second is instantiated. ? $x = new stdClass(); $y = new stdClass(); var_dump(spl_object_hash($x), spl_object_hash($y)); ? This yields a difference. -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
Not quite. It creates a hash of an object, so two objects with the
same data yield the same hashes:
var_dump(spl_object_hash(new stdClass()), spl_object_hash(new stdClass
()));
Folks, is this really wanted behavior? Because if so, why does the
following result in the same hash as well(PHP-5.2.1)?
$ php -r class Foo{};$foo = new
Foo();var_dump(spl_object_hash($foo));$foo-bar =
1;var_dump(spl_object_hash($foo));
string(32) d1f40a1cc04d8c79d09ae6262666adbb
string(32) d1f40a1cc04d8c79d09ae6262666adbb
- David
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Re: [PHP-DEV] toString() and Object #ID
The first is cleared before the second is instantiated. Oh, that clears everything, please ignore my previous post. Still, don't you think this is a bit misleading? IMHO, new object should always have the unique id(or hash in terms of spl)... -- Best regards, Pavel -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
Oh, that clears everything, please ignore my previous post. Still, don't you think this is a bit misleading? IMHO, new object should always have the unique id(or hash in terms of spl)... I don't like it either;) But it does exactly what Stanislav Malyshev described: it hashes the tuple of C pointer. Misleading in this case is that this is only unique as long as the compared objects exist at the same time...then they can't inhabit the same memory-space. But because php clears and reuses memory as soon as no pointers to the object exist (reference counting). In this case php uses the exact same tuple of C pointer for the next object as the for the previous one. At least...that's my interpretation of this behaviour;) -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
Not quite. It creates a hash of an object, so two objects with the same data yield the same hashes: var_dump(spl_object_hash(new stdClass()), spl_object_hash(new stdClass())); here's the code of spl_object_hash: len = spprintf(hash, 0, %p:%d, Z_OBJ_HT_P(obj), Z_OBJ_HANDLE_P(obj)); md5str[0] = '\0'; PHP_MD5Init(context); PHP_MD5Update(context, (unsigned char*)hash, len); PHP_MD5Final(digest, context); make_digest(md5str, digest); RETVAL_STRING(md5str, 1); See any mention of object data? It's not there. -- Stanislav Malyshev, Zend Software Architect [EMAIL PROTECTED] http://www.zend.com/ (408)253-8829 MSN: [EMAIL PROTECTED] -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
The first is cleared before the second is instantiated. Oh, that clears everything, please ignore my previous post. Still, don't you think this is a bit misleading? IMHO, new object should always have the unique id(or hash in terms of spl)... That's a valid point, reusing IDs might be not a good idea. Not reusing them though might not help either - you have only so much IDs in long, so eventually it might happen that IDs from two objects that existed at different time coincide. spl_object_hash guarantees that no two hashes of two simultaneously existing objects are the same, but it would be very hard to guarantee that no objects that ever existed have the same hash. -- Stanislav Malyshev, Zend Software Architect [EMAIL PROTECTED] http://www.zend.com/ (408)253-8829 MSN: [EMAIL PROTECTED] -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
Guys thank you all very much for this detailed explanation! spl_object_hash is unique in the terms of object identity. I really don't want to be annoying but from the end user's POV spl_object_hash sounds like a function which returns a hash but not an identity. Any tiny chance it will be available as object_get_id in PHP6? ;) -- Best regards, Pavel -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
I really don't want to be annoying but from the end user's POV spl_object_hash sounds like a function which returns a hash but not an identity. Any tiny chance it will be available as object_get_id in PHP6? ;) It does give the hash, which is unique for each object. In which form would you expect object_get_id to return object's identity? PHP doesn't have a type of tuple of C pointer and long integer ;) -- Stanislav Malyshev, Zend Software Architect [EMAIL PROTECTED] http://www.zend.com/ (408)253-8829 MSN: [EMAIL PROTECTED] -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
Stanislav Malyshev schrieb: It does give the hash, which is unique for each object. In which form would you expect object_get_id to return object's identity? PHP doesn't have a type of tuple of C pointer and long integer ;) We could add a counter that gets incremented for each object that is created and associate that number with the object. Wouldn't that solve the problem (if there is one)? -- Sebastian Bergmann http://sebastian-bergmann.de/ GnuPG Key: 0xB85B5D69 / 27A7 2B14 09E4 98CD 6277 0E5B 6867 C514 B85B 5D69 -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
We could add a counter that gets incremented for each object that is created and associate that number with the object. Wouldn't that solve the problem (if there is one)? It would solve it, but it would require modifying each extension dealing with objects in order to register all objects in this global registry and of course it would require adding another value into object structure. I'm not sure having running numeric ID is that important. If you just need to know if two variables are the same object, you have ===. If you need to index by it, you have the hash. -- Stanislav Malyshev, Zend Software Architect [EMAIL PROTECTED] http://www.zend.com/ (408)253-8829 MSN: [EMAIL PROTECTED] -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
RE: [PHP-DEV] toString() and Object #ID
(Many apologies for the double e-mail. Ugh, I'm not used to hitting Reply To All yet) I really don't want to be annoying but from the end user's POV spl_object_hash sounds like a function which returns a hash but not an identity. Any tiny chance it will be available as object_get_id in PHP6? ;) It does give the hash, which is unique for each object. In which form would you expect object_get_id to return object's identity? PHP doesn't have a type of tuple of C pointer and long integer ;) Hmm. I think what Pavel is asking is just to make it clearer in the documentation what spl_object_hash's purpose and workings are, and perhaps make an alias to it named object_get_id so other people don't run into this confusion in the future. The name of spl_object_hash and the fact it is in the SPL and not in the engine does lead one to believe that it might do more than simply hashing the handler table and handle tuple. People might think it hashes the properties as well. David -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
Hmm. I think what Pavel is asking is just to make it clearer in the documentation what spl_object_hash's purpose and workings are, and perhaps make an alias to it named object_get_id so other people don't run into this confusion in the future. The name of spl_object_hash and the fact it is in the SPL and not in the engine does lead one to believe that it might do more than simply hashing the handler table and handle tuple. People might think it hashes the properties as well. Exactly, this is what I wanted to say, thanks ;) David -- Best regards, Pavel -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
On 02.07.2007 22:16, David wrote: (Many apologies for the double e-mail. Ugh, I'm not used to hitting Reply To All yet) I really don't want to be annoying but from the end user's POV spl_object_hash sounds like a function which returns a hash but not an identity. Any tiny chance it will be available as object_get_id in PHP6? ;) It does give the hash, which is unique for each object. In which form would you expect object_get_id to return object's identity? PHP doesn't have a type of tuple of C pointer and long integer ;) Hmm. I think what Pavel is asking is just to make it clearer in the documentation what spl_object_hash's purpose and workings are That's fine, the docu team would gladly accept any help and patches. and perhaps make an alias to it named object_get_id so other people don't run into this confusion in the future. I'd like to avoid creating misleading aliases, which would not be usable on a shared hosting in the next 10 years anyway. The name of spl_object_hash and the fact it is in the SPL and not in the engine does lead one to believe that it might do more than simply hashing the handler table and handle tuple. People might think it hashes the properties as well. People won't think anything like that if we fix the documentation, so let's do it. -- Wbr, Antony Dovgal -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
On 6/30/07, Stanislav Malyshev [EMAIL PROTECTED] wrote: always helpful). Is there any other way than casting an object to a string to get an objects #ID? spl_object_hash? Guys, excuse my being a little offtopic here, but why not introduce standard get_object_id function in PHP6 which could be analogous to spl_object_hash? IMHO it's a basic functionality which deserves to be in the core... -- Best regards, Pavel -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
On Jul 1, 2007, at 3:24 AM, Pavel Shevaev wrote: always helpful). Is there any other way than casting an object to a string to get an objects #ID? spl_object_hash? Guys, excuse my being a little offtopic here, but why not introduce standard get_object_id function in PHP6 which could be analogous to spl_object_hash? IMHO it's a basic functionality which deserves to be in the core... +1 on PHP_FEALIAS()ing this. -- Gwynne, Daughter of the Code This whole world is an asylum for the incurable. -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
Pavel Shevaev schrieb: Guys, excuse my being a little offtopic here, but why not introduce standard get_object_id function in PHP6 which could be analogous to spl_object_hash? IMHO it's a basic functionality which deserves to be in the core... SPL is in the core AFAIAC. -- Sebastian Bergmann http://sebastian-bergmann.de/ GnuPG Key: 0xB85B5D69 / 27A7 2B14 09E4 98CD 6277 0E5B 6867 C514 B85B 5D69 -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
Hello Gwynne, no more unnecessary aliases please. marcus Sunday, July 1, 2007, 9:27:25 AM, you wrote: On Jul 1, 2007, at 3:24 AM, Pavel Shevaev wrote: always helpful). Is there any other way than casting an object to a string to get an objects #ID? spl_object_hash? Guys, excuse my being a little offtopic here, but why not introduce standard get_object_id function in PHP6 which could be analogous to spl_object_hash? IMHO it's a basic functionality which deserves to be in the core... +1 on PHP_FEALIAS()ing this. -- Gwynne, Daughter of the Code This whole world is an asylum for the incurable. Best regards, Marcus -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
SPL is in the core AFAIAC. I really want to hope it will be in PHP6. Still IMHO get_object_id sounds much better than spl_object_hash and it will be much easier(and more logical) to locate this function in Class/Object Functions section of documentation than in SPL... -- Best regards, Pavel -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
Hello Pavel, technically object id is neither what you get nor what you want. It is not unique and thus not helpfull and we have no intention to ever provide a function to access it. See mail archieve for reference on why we won't. Also the function resides in extension SPL so correctly it is prefixed with 'spl_'. Furthermore it is no engine specific function but an object oriented programming specific one. So SPL indeed is a very good place for it. Lastly the function per design hashes the unique input it gives as we do not want to make it more complex than necessary or give you stuff that leads to missuse. Again see mail archive for why. That said the name appears to be the best option already. marcus Sunday, July 1, 2007, 1:42:02 PM, you wrote: SPL is in the core AFAIAC. I really want to hope it will be in PHP6. Still IMHO get_object_id sounds much better than spl_object_hash and it will be much easier(and more logical) to locate this function in Class/Object Functions section of documentation than in SPL... -- Best regards, Pavel Best regards, Marcus -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
Again see mail archive for why. That said the name appears to be
the best option already.
Oh, yes, you're right spl_object_hash does its job and does it very
well, there's really no point rename it(or make an alias) into
object_get_id. I should have stated more clear what I think
object_get_id could actually be.
How about object_get_id being a function returning the very first line
of var_dump's output being applied to the object? Let me be a bit more
specific, here's an example of var_dump usage:
$ php -r class Foo{};$foo = new Foo();var_dump($foo);
object(Foo)#1 (0) {
}
What I actually need, not the object hash but simply its unique id.
And in this case object(Foo)#1 would be just fine. How can I get it?
The only way AFAIK is to surround var_dump with
ob_start/ob_get_contents/ob_end_clean functions and extract this
value.
The problem with approach is if one has a complex object connected
with a graph of other complex objects(with recursive links) var_dump
may take a _very_ long time to complete.
And this is what object_get_id could do - simply return object id
prefixed with the class name.
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Re: [PHP-DEV] toString() and Object #ID
What I actually need, not the object hash but simply its unique id.
And in this case object(Foo)#1 would be just fine. How can I get it?
That was my original Question too;) It's been stated that the automatic
cast into a string even if it does not implement the __toString()
function was absolute nonsense...but it really helped alot when you
needed to check for errors quickly and easily. Why make something harder
than it has to be.
Why not allow the old behaviour as long as the __toString is not
implemented? Or rather something like a default implementation which is
used autmatically for every class which doesn't implement it itself?
public function __toString(){
return 'Object '. get_class($this) .'('. get_object_id($this) .')';
}
That'd be nice and no code breakage would result. Isn't that an approach
that fits into the PHP philosophy? The new behaviour reminds me of
Java's the more userland-code, the better.
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Re: [PHP-DEV] toString() and Object #ID
Pavel Shevaev schrieb: What I actually need, not the object hash but simply its unique id. The problem is that there is no such unique id in the current engine. -- Sebastian Bergmann http://sebastian-bergmann.de/ GnuPG Key: 0xB85B5D69 / 27A7 2B14 09E4 98CD 6277 0E5B 6867 C514 B85B 5D69 -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
The problem is that there is no such unique id in the current engine. Okay!;) That's a very good reason, I guess;) Explains a lot. Why not use spl_object_hash instead of the old default behaviour? -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
The problem is that there is no such unique id in the current engine. Am I right in my guess that there's only a counter for each object type? Still being not really unique this information could be very useful and enough in many situations. -- Best regards, Pavel -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
RE: [PHP-DEV] toString() and Object #ID
(accidentally didn't send this to the whole group at first) Am I right in my guess that there's only a counter for each object type? Still being not really unique this information could be very useful and enough in many situations. The counter is global, but it's not really a counter. Object ids are actually handles (basically indices) into an internal array holding data to all objects currently in memory. Handles are reused when an object is destroyed so that the array could be kept as small as possible. However, if you are comparing the handles of two objects that are known to be currently in memory, if they have the same handle, then they are the same object (i.e. one spot in memory). However, if you stored the handle of the object in another area of memory so that you can check it against other objects later, it's hard to ensure that the results of that comparison is meaningful. Therefore, it's better to use spl_object_hash to actually ensure objects are the same. Internally, the hash is performed on the object handle (what you've been calling the object id) as well as the internal list of handlers for that object (basically the type of the object), so there's reasonable confidence that a unique hash will be generated. It looks like it's independent of the actual properties, etc. of the object. Spl_object_hash is what you guys want. David -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
will be generated. It looks like it's independent of the actual properties, etc. of the object. Spl_object_hash is what you guys want. Sure, object identity is not related to properties in any way. Same object can have different properties during the lifetime, and different objects can have identical properties. spl_object_hash is unique in the terms of object identity. -- Stanislav Malyshev, Zend Software Architect [EMAIL PROTECTED] http://www.zend.com/ (408)253-8829 MSN: [EMAIL PROTECTED] -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
Hi Lars, In the meanwhile .. check out spl_object_hash Evert Lars Schultz wrote: Hi there I just tried to switch from 5.1 to 5.2.3 and got thrown off right away by: Object of class MyObject could not be converted to string I googled a bit and also read any Messages in the internals list but couldn't find a decisive answer as to wether this will stay this way or not. In the PHP 5 Bug Summary Report I found Bug # 40799 change string conversion behaviour for objects not implementing __toString() which is still open. I don't want to complain or anything but I'd like to know wether it's feasible to wait for a change in this current, modified, behaviour or if it's going to stay this way. I used the previous behaviour mostly for debugging purposes where I wanted to get a visual (string) handle for any given object, which helps ALOT when trying to figure out wether one has a copy or the original and wether to references point to the same object(obj1 === obj2 is not always helpful). Is there any other way than casting an object to a string to get an objects #ID? Thanks for your time. Lars -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
always helpful). Is there any other way than casting an object to a string to get an objects #ID? spl_object_hash? -- Stanislav Malyshev, Zend Software Architect [EMAIL PROTECTED] http://www.zend.com/ (408)253-8829 MSN: [EMAIL PROTECTED] -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP-DEV] toString() and Object #ID
On 6/29/07, Lars Schultz [EMAIL PROTECTED] wrote: Hi there I just tried to switch from 5.1 to 5.2.3 and got thrown off right away by: Object of class MyObject could not be converted to string I googled a bit and also read any Messages in the internals list but couldn't find a decisive answer as to wether this will stay this way or not. In the PHP 5 Bug Summary Report I found Bug # 40799 change string conversion behaviour for objects not implementing __toString() which is still open. I don't want to complain or anything but I'd like to know wether it's feasible to wait for a change in this current, modified, behaviour or if it's going to stay this way. The old beahviuor was absolute non-sense.. always helpful). Is there any other way than casting an object to a string to get an objects #ID? use var_dump() or spl_object_hash for that. -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
