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Re: An overloading question

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On 6/14/2011 7:43 PM, sheldonlg wrote:
> On 6/14/2011 7:12 PM, Jerry Stuckle wrote:
>> On 6/14/2011 6:27 PM, sheldonlg wrote:
>>> On 6/14/2011 2:32 PM, Denis McMahon wrote:
>>>> On Tue, 14 Jun 2011 12:49:11 -0400, sheldonlg wrote:
>>>>
>>>>> I have a problem that I am wrestling with that should be so obvious
>>>>> and
>>>>> easy -- but it isn't. I have a base class that has a method that calls
>>>>> another method in the base class with $this->thatOtherMethod. I have
>>>>> another class that extends the base class and I want to have
>>>>> thatOtherMethod in the extended class override the one in the base
>>>>> class. The calling method in the base class is called using and
>>>>> instance of the extended class pointing to that method.
>>>>>
>>>>> Simply, here is an example:
>>>>>
>>>>> A.class.php
>>>>> --------------------------
>>>>> <?php
>>>>> abstract class A {
>>>>> public function b() {
>>>>> $this->a();
>>>>> }
>>>>> protected function a() {
>>>>> print 'In class A';
>>>>> }
>>>>> }
>>>>> ?>
>>>>>
>>>>> B.class.php
>>>>> ---------------------------
>>>>> <?php
>>>>> include_once 'A.class.php';
>>>>> class B extends A {
>>>>> public function a() {
>>>>> print 'In class B';
>>>>> }
>>>>> }
>>>>> ?>
>>>>>
>>>>> c.php
>>>>> ----------------------------
>>>>> <?php
>>>>> include 'B.class.php';
>>>>> $x = new B();
>>>>> $x->b();
>>>>> ?>
>>>>> ----------------------------
>>>>>
>>>>> I want it to print out "In class B", but it prints out "In class A".
>>>>>
>>>>> I have looked over Google quite a bit and found nothing that helped. I
>>>>> have tried making the methods public, protected, keep them both the
>>>>> same
>>>>> access, etc. and have had no luck. Suggestions?
>>>>
>
>> Unfortunately, PHP doesn't really implement OO constructs very well - in
>> fact they to a pretty piss poor job of it. One of the problems is with
>> virtual functions, as you found. A good OO language would work like you
>> want, but PHP doesn't - the constructor for A will, in this case, only
>> call a function in A. In C++, Smalltalk, Java and most other OO
>> languages, you could define y() as virtual and the constructor for A
>> would call the function y() in B.
>
> I could define the method in A as abstract (and the class). It would
> then require that it be implemented in B. However, I am not the only
> application using A, and so doing that would require all the other apps
> to also implement it in an extended class. That is a no-no and is one of
> the reasons for using B in the first place.
>
>>
>> But if you created a constructor in B properly, it should call B:y().
>
> I did create a constructor in B properly.
>
>> I'd suggest checking your code again - you might have made a mistake.
>>
>
> No mistakes that I could find.
>

Id you created it properly, then the constructor in B should be calling 
b::y().

I still suggest you have a mistake in your code.

-- 
==================
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
jstucklex@attglobal.net
==================

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An overloading question sheldonlg <sheldonlg@thevillages.net> - 2011-06-14 12:49 -0400
  Re: An overloading question Denis McMahon <denis.m.f.mcmahon@gmail.com> - 2011-06-14 18:32 +0000
    Re: An overloading question sheldonlg <sheldonlg@thevillages.net> - 2011-06-14 18:27 -0400
      Re: An overloading question Jerry Stuckle <jstucklex@attglobal.net> - 2011-06-14 19:12 -0400
        Re: An overloading question sheldonlg <sheldonlg@thevillages.net> - 2011-06-14 19:43 -0400
          Re: An overloading question Jerry Stuckle <jstucklex@attglobal.net> - 2011-06-14 20:45 -0400
            Re: An overloading question sheldonlg <sheldonlg@thevillages.net> - 2011-06-14 21:58 -0400
              Re: An overloading question Jerry Stuckle <jstucklex@attglobal.net> - 2011-06-14 22:08 -0400
              Re: An overloading question Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2011-06-15 14:21 +0200
              Re: An overloading question sheldonlg <sheldonlg@thevillages.net> - 2011-06-15 12:55 -0400
        Re: An overloading question Michael Fesser <netizen@gmx.de> - 2011-06-15 18:04 +0200
          Re: An overloading question Jerry Stuckle <jstucklex@attglobal.net> - 2011-06-15 12:53 -0400
      Re: An overloading question Denis McMahon <denis.m.f.mcmahon@gmail.com> - 2011-06-15 03:41 +0000
      Re: An overloading question Michael Fesser <netizen@gmx.de> - 2011-06-15 18:02 +0200
  Re: An overloading question Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2011-06-15 14:01 +0200

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