#34358 [Csd->Opn]: Fatal error: Cannot re-assign $this(again)

ID: 34358 Updated by: derick@php.net Reported By: pacha dot shevaev at gmail dot com -Status: Closed +Status: Open Bug Type: Scripting Engine problem Operating System: * PHP Version: 5.* Assigned To: dmitry New Comment: I'm reopening this so that we can discuss it. I don't think we should be silently ignoring references as that's something vague. See mail to internals@ in a bit. Previous Comments: ------------------------------------------------------------------------ [2005-10-03 12:14:59] rasmus@php.net So for the curious who are wondering what "fixed" means. The & is simply ignored in this case now. ------------------------------------------------------------------------ [2005-10-03 10:22:47] dmitry@php.net Fixed in CVS HEAD and PHP_5_1. ------------------------------------------------------------------------ [2005-10-03 09:40:14] rasmus@php.net It has everything to do with the new object model. Take this code: $x = &$this; $x = 'foo'; For performance reasons we need to catch such references when they happen in order to prevent the object being overwritten inside itself. It would be a bit less confusing if the error happened on the actual assignment, but in this new object model there $x = &$this; is just as wrong as $this = &$x since the only purpose one could have for making a reference to $this itself is if you wanted to change it directly. In all valid cases this should be $x = $this. I suppose an option would be to ignore the reference in this case and continue on. That seems to be happening with that last indirect case you posted, but it would cost us a lookup. ------------------------------------------------------------------------ [2005-09-15 15:32:13] pacha dot shevaev at gmail dot com And why does the following code work then??? <?php class Foo { function Foo() { $this->ref =& $this; $this->ref->test(); } function test() { echo 'test'; } } $foo = new Foo(); ?> ------------------------------------------------------------------------ [2005-09-15 15:28:02] derick@php.net It's still bogus, you can call it a BC break if you want, but we're not going to change this back. ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at http://bugs.php.net/34358 -- Edit this bug report at http://bugs.php.net/?id=34358&edit=1