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Date: Fri, 13 Apr 2012 17:27:32 -0400
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To: Stas Malyshev <smalyshev@sugarcrm.com>
Cc: Dmitri Snytkine <dsnytkine@ultralogistics.com>, PHP Internals <internals@lists.php.net>
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Subject: Re: [PHP-DEV] Ability to assign new object to a class property.
From: ircmaxell@gmail.com (Anthony Ferrara)

Stas,

> Because the engine doesn't run code when parsing class definitions so
> defaults should be constants (otherwise would also create a lot of
> trouble for bytecode caching as object are not cacheable).

Just throwing this out there, but that code wouldn't be run on parse.
It would be "queued" to run prior to the constructor on instantiation.
 So then, we should be able to execute that code inside of
_object_and_properties_init...  Then, all you'd need to do is add a
single field to _zend_property_info to indicate it should be a class
instantiation.  From there, you'd want a flag on zend_class_entry to
indicate if it has any dynamic properties.

So the work flow would be that in _object_and_properties_init, when it
copies the hash table, check the flag on the zce.  If true, iterate
over the properties to check for instantiation, and if so, do it.

This would (in theory) be able to support almost any type of dynamic
code in the property declaration, as long as it doesn't reference
`$this` (which would still be undefined at that point).  So you could
do:

protected $foo = "bar" . BAZ;
protected $fiz = new Biz(new Baz, array(123));

Just a thought...

Anthony


On Fri, Apr 13, 2012 at 4:06 PM, Stas Malyshev <smalyshev@sugarcrm.com> wrote:
> Hi!
>
>> Why can't we create a new object and assign it to property like this?
>
> Because the engine doesn't run code when parsing class definitions so
> defaults should be constants (otherwise would also create a lot of
> trouble for bytecode caching as object are not cacheable).
>
> Use ctor for complex initializations.
>
> --
> Stanislav Malyshev, Software Architect
> SugarCRM: http://www.sugarcrm.com/
> (408)454-6900 ext. 227
>
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