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Date: Tue, 6 Jul 2004 06:15:31 -0400
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Subject: extended objects with read_property and get_property_ptr_ptr
From: rrichards@ctindustries.net ("Rob Richards")

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I was playing around with Bug #28817 and seem to have run into an issue =
when overriding the read_property handler with an extended object (this =
case a DomDocument object).

In order to support standard properties correctly, such as =
$obj->myprop['a'] =3D 'b', the internal object needs to support =
get_property_ptr_ptr. As the internal object here overrides the =
read_property handler, it would also need to override the =
get_property_ptr_ptr handler to make that standard property work =
correctly, which is where I have run into some problems.

At first, I implemented a get_property_ptr_ptr handler, but found that =
for the base internal class properties, this method needs to return NULL =
so that cases like zend_pre_incdec_property would fall back to the =
read_property/write_property handling. Next was to return NULL for all =
properties of the base internal class and return the result of the =
standard get_property_ptr_ptr for non base class properties. This fixed =
the standard properties, but returning NULL for the internal base =
properties breaks calls like:
$document->documentElement->ownerDocument;
because zend_fetch_property_address_inner will not fall back to the =
read_property handler if NULL is returned get_property_ptr_ptr.
Rather the error "Cannot access undefined property for object with =
overloaded property access" is returned.

Is this is a pitfall of the engine or is there something I am =
overlooking which would allow this to work across all cases?

Thanks,

Rob
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