Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:19937
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Message-ID: <6.2.3.4.2.20051109141302.037967b0@localhost>
Date: Wed, 09 Nov 2005 14:15:08 -0800
To: "Thies C. Arntzen" <thies@thieso.net>,internals@lists.php.net
Cc: Thies Arntzen <thies@thieso.net>
In-Reply-To: <81D9588B-8984-432C-91CB-9ECE28F573F0@thieso.net>
References: <81D9588B-8984-432C-91CB-9ECE28F573F0@thieso.net>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"; format=flowed
Subject: Re: [PHP-DEV] object-overloading: why not allow recursive
	calls? (5.1)  hey,  in zend_object_handlers.c function
	zend_std_read_property we protect against calling the __get function
	of an object if we're already in a __get() function. (look for 
From: andi@zend.com (Andi Gutmans)

This is intentional and I think it makes it much more fool-proof for 
developers. Adding recursion protection can be very expensive and 
complicated, and it doesn't seem to make sense here. The idea is that 
once you're in the __get() method, you know exactly how your 
properties are mapped and can do the right thing. It's only this one 
method where you have your mapping anyway, not an entirely different place.

Andi

At 12:35 AM 11/4/2005, Thies C. Arntzen wrote:
>hey,
>
>in zend_object_handlers.c function zend_std_read_property we protect
>against calling the __get function of an object if we're already in a
>__get() function. (look for zobj->in_get) in that function.
>
>i don't think we should be doing this.
>
>simplyfied example:
><?php
>class test {
>     function __get($offset) {
>         echo "__get($offset)\n";
>         switch ($offset) {
>             case 'name': return "name";
>             case 'length': return strlen($this->name);
>         }
>     }
>}
>
>$a = new test;
>var_dump($a->length);
>?>
>
>outputs:
>__get(length)
>int(0)
>
>but should say:
>__get(length)
>__get(name)
>int(4)
>
>i think recursive gets are highly useful and should be allowed. if we
>really want to protect against recursion (here) we have two real
>options: -a- protect against __get(ing) the same property more than
>once in the same call-chain (mucho work), or -b- (preferred) have
>some global infinite recursion protection in the engine (needs to be
>done somewhen anyhow, but not now).
>
>so, in one sentence: as we don't protect against recustion elsewhere,
>can we please remove this unneded roadblock?
>
>opinions?
>-thies
>
>--
>PHP Internals - PHP Runtime Development Mailing List
>To unsubscribe, visit: http://www.php.net/unsub.php