Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:22044
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Date: Wed, 1 Mar 2006 11:00:31 +0100
Reply-To: Marcus Boerger <helly@php.net>
Message-ID: <1356201130.20060301110031@marcus-boerger.de>
To: PHP-DEV <internals@lists.php.net>
Cc: Andi Gutmans <andi@zend.com>, Mike Lively <mlively@ft11.com>
In-Reply-To: <1140732362.3702.14.camel@localhost.localdomain>
References: <1140732362.3702.14.camel@localhost.localdomain>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Subject: Re: [PHP-DEV] [PATCH] Late Static Binding
From: helly@php.net (Marcus Boerger)

Hello internals,

   it looks like either nobody objects or nobody has interest. Either way
i tested the patch and worked helped it a bit and it looks good, doesn't
affect anything else and doesn't show a single problem in valgrind. So If
noone objects i will commit this next week.

regards
marcus

special mail to andi :-)


Thursday, February 23, 2006, 11:06:02 PM, you wrote:

> I have finished a patch that implements a working version of late static
> binding.

> I used the notes from the Paris PDM as my guidelines for implementation.
> (http://www.php.net/~derick/meeting-notes.html#late-static-binding-using-this-without-or-perhaps-with-a-different-name)
> As requested in the notes I reused 'static::'. I also wrote a few tests
> not only to test the new functionality but also to make sure 'static' can't be inherited or extended.

> I also added a new function get_caller_class() which returns the name of
> the class that static:: would represent.

> (borrowing from PDM notes)
> In php5.* the following script outputs "A::static2":

> <?php
>         class A {
>                 static function staticA() {
>                         self::static2();
>                 }

>                 static function static2() {
>                         echo "A::static2\n";
>                 }
>         }

>         class B extends A {
>                 static function static2() {
>                         echo "B::static2\n";
>                 }
>         }

>         B::staticA();
?>>

> This has somewhat recently been highlighted by different developers to
> be somewhat problematic behavior in creating user friendly APIs. If you
> want to see a possible use for it you need look no further than the
> example ZActiveRecord API that was used in their webcast with php|arch.
> (http://blog.joshuaeichorn.com/archives/2006/01/09/zactiverecord-cant-work/)
> Currently the code laid out there is impossible short of some ugly use of
> debug_backtrace() and file parsing :/. This patch of course would allow that kind of code too exist.

> In a small example based on the one I gave earlier you could change the
> code too the following and have it print "B::static2":

> <?php
>         class A {
>                 static function staticA() {
>                         static::static2();
>                 }

>                 static function static2() {
>                         echo "A::static2\n";
>                 }
>         }

>         class B extends A {
>                 static function static2() {
>                         echo "B::static2\n";
>                 }
>         }

>         B::staticA();
?>>

> As far as current userland code impact, there is very little as far as I
> can tell. No keywords have been added, just another use for an existing
> one. No changes were made to self:: or parent:: so the change should be
> pretty transparent. The only thing that I see remotely causing any
> issues would be the new function (get_caller_class().) I added that just
> to complete the set so to speak.