cast_object() handler

Hi, Attached is a patch which allows one to intercept calls to object casting within the engine. This means that whenever an object is converted to a base type (except array, which has different semantics), a special object handler is called instead of the default conversion function. I've come across a need for this when implementing the simplexml extension, where i want an object to masquerade as either a string or a node. Take the following: slide.xml <?xml version="1.0"?> <slide> <list> <bullet effect="slide">Why SimpleXML is cool</bullet> </list> </slide> With this new callback, the following syntax is perfectly valid: <?php $list = simplexml_load_file('slide.xml')->list; echo $list->bullet; // "Why SimpleXML is cool" echo $list->bullet->effect; // "slide" ?> Attached is a patch that makes this so. It only affects objects, and it is only a internal syntax (not exported to userspace). Every other place in the code that doesn't exploit this callback (sets it to NULL) will continue to operate as normal. -Sterling