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Date: Wed, 11 Mar 2009 23:35:27 +0100
Reply-To: Marcus Boerger <helly@php.net>
Message-ID: <306205231.20090311233527@marcus-boerger.de>
To: Nate Abele <nate@cakephp.org>
CC: PHP Development <internals@lists.php.net>
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Subject: Re: [PHP-DEV] Questions on closures and visibility
From: helly@php.net (Marcus Boerger)

Hello Nate,

Wednesday, March 11, 2009, 9:25:23 PM, you wrote:

> Hi all,

> Since around alpha1, I've been doing some experimenting with closures,  
> most recently in the form of a filter chain implementation, and I've  
> discovered that as of beta1 (as was noted in the "removal-of-$this"  
> RFC) that there is no way to access private or protected members of  
> any class inside a closure, regardless of where it is defined.

> I realize that the question of implicit $this support for closures has  
> already been discussed and decided upon temporarily (and I certainly  
> have no wish to rehash it again), however, it seems logical that even  
> without being bound to an object, closures should still inherit the  
> scope in which they're defined.  Otherwise, this creates a confusing  
> inconsistency within the language.

At the moment it simply is impossible to allow $this. Simply becasue we
could not solve resolving it correctly, or figuring out the scope
correctly. An attempt of mine to solve the issues first looked good and
then just brought up more issues and the only way to solve them was to
make everything slower. So we decided to keep closures as external entities
that are not bound to the scope they are created in. In the same way we do
not bind anythign magically. Also it appears that you probably want a real
callback if you ave to access private or protected members. At least from
a pure design stanpoint that is more than obvious. Please leave it for the
moment, we are far to close in PHP 5.3 release process to do somethign
about it now.

Best regards,
 Marcus