Edit report at http://bugs.php.net/bug.php?id=53138&edit=1

 ID:                 53138
 Updated by:         cataphr...@php.net
 Reported by:        tom at r dot je
 Summary:            __instanceof magic method
-Status:             Open
+Status:             Bogus
 Type:               Feature/Change Request
 Package:            *General Issues
 Operating System:   N/A
 PHP Version:        5.3.3
 Block user comment: N

 New Comment:

Make A an interface and have AWrapper implement or extend A.



Overloading the instanceof operator is not an acceptable solution.


Previous Comments:
------------------------------------------------------------------------
[2010-10-22 13:00:23] tom at r dot je

Description:
------------
as it stands, it's possible to create a wrapper e.g.





<?php

class A {

        

}



class AWrapper {

        protected $a;

        

        public function __construct(A $a) {

                $this->a = $a;

        }

        

        public function __set($name, $value) {

                $this->a->$name = $value;

        }

        

        public function __get($name) {

                return $this->a->$name;

        }

        

        public function __call($func, $args) {

                return call_user_func_array(array($this->a, $func), $args);

        }

}

?>



AWrapper, now mimics the interface of A. It will work as a substitute
for A, anywhere A is required.



The problem is, type checking. Anywhere class "A" is used, it may be
type hinted or checked using instanceof



e.g.



function setA(A $a) {



}



or $foo isntanceof 'A';



If an __instanceof magic method existed, it would  be possible to get
around this and have true wrapper classes.



For example: 



public function __instanceof() {

        return 'A';

}



Or perhaps it should return an array to allow it to wrap multiple
classes.





------------------------------------------------------------------------



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