#43499 [Fbk->Opn]: Inproper use of extending class method from extended class.
| From: | bholbrook at servillian dot com | Date: | Wed, 05 Dec 2007 16:41:54 +0000 |
| Subject: | #43499 [Fbk->Opn]: Inproper use of extending class method from extended class. | ||
| References: | 1 | Groups: | php.bugs |
| Request: | Send a blank email to php-bugs+get-120396@lists.php.net to get a copy of this message | ||
ID: 43499
User updated by: bholbrook at servillian dot com
Reported By: bholbrook at servillian dot com
-Status: Feedback
+Status: Open
Bug Type: Scripting Engine problem
Operating System: Linux Cent OS
PHP Version: 5.2.5
New Comment:
$oB->method2() should work, but the call $this->method3() from
A::method1() should cause the same fatal error seen when calling it
through $oC->method4();
Class A should have no knowledge of it's extending classes methods.
Previous Comments:
------------------------------------------------------------------------
[2007-12-05 10:59:36] jani@php.net
Output:
I am method B::method2
I am method A::method1
I am method B::method3
I am method C::method4
I am method A::method1
Fatal error: Call to undefined method C::method3() in /home/jani/t.php
on line 6
Exactly what is wrong in this? AFAICT, it works exactly how it's
supposed to work.
------------------------------------------------------------------------
[2007-12-04 22:36:54] bholbrook at servillian dot com
Description:
------------
In the example, class A gains a knowledge of it's extending classes
functions. By allowing the call from the entended class to an extending
class method, the extended class method becomes unavailable to any other
extending class.
The only time this makes sense is if class A were an abstract class and
defined method3 as an abstract function.
Reproduce code:
---------------
<?php
class A {
public function method1(){
echo "I am method A::method1<br/>";
$this->method3();
}
}
class B extends A{
public function method2(){
echo "I am method B::method2<br/>";
$this->method1();
}
public function method3(){
echo "I am method B::method3<br/>";
}
}
class C extends A{
public function method4(){
echo "I am method C::method4<br/>";
$this->method1();
}
}
$oB = new B();
$oB->method2();
$oC = new C();
$oC->method4();
?>
Expected result:
----------------
The expected result of $oB->method2(); is the current results of
$oC->method4();
Actual result:
--------------
Currently, $oB->method2() calls A::method1() (correct) which in turn
calls B::method3() (incorrect).
------------------------------------------------------------------------
--
Edit this bug report at http://bugs.php.net/?id=43499&edit=1