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Date: Tue, 19 Mar 2013 23:19:10 +0200
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To: =?UTF-8?Q?Johannes_Schl=C3=BCter?= <johannes@schlueters.de>
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Subject: Re: [PHP-DEV] Proposal: new magic methods for Object references.
From: mrtreinis@gmail.com (=?UTF-8?Q?Mat=C4=ABss_Roberts_Treinis?=)

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2013/3/19 Johannes Schl=C3=BCter <johannes@schlueters.de>

>
>
> "Mat=C4=ABss Roberts Treinis" <mrtreinis@gmail.com> wrote:
>
> >Proposal:
> >
> >Two additional magic methods for PHP objects -
> >
> >__refer(void):
> >
> >Refer method is called whenever object's identifier is assigned to
> >variable, if such method is present.
> >Example:
> >
> >$foo =3D new Bar;
> >$bar =3D $foo; //__refer invoked
>
> This assignment is handled using PHP's copy on write mechanism for any
> variable. A change here has massive impact on any variable assignment,
> function parameter passing, ... and tons of internal places.
>
> What we have is a hook for the objects own reference counting which is
> affected when an object refering to an object is used in write-context by
> the engine, that might easily be exteded but is rather useless. (It's
> trivial to create an interface or abstract base class providing this
> addref/delref info)
>
> Unless you can provide a robust good patch without performance penalty in
> cases where this isn't used this will lead nowhere, and I doubt there is =
a
> way to come up with that. (rewriting the engine might be the closest
> approach)
>
> johannes
>
>
I doubt my ability to rewrite engine in reasonable amount of time. With
that, I mean, lifespan of the universe at least.

However, as far as I understand, variables can currently hold values like
arrays, strings, etc, and object references. Could it be possible to add
one more possible value to this keen little list - like special type of
reference? Therefore we could only take a special care only on those
references which are known to be bound to objects which does posses __refer
and __unrefer, therefore effect on rest of the variable operations could be
brought to minimum and overhead would only affect those special objects.

Also, a little overhead is reasonable for the new functionality. It is not
like we have Pentium 2's in our DC's anymore.

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