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Re: An overloading question

From sheldonlg <sheldonlg@thevillages.net>
Newsgroups comp.lang.php
Subject Re: An overloading question
Date 2011-06-14 19:43 -0400
Organization A noiseless patient Spider
Message-ID <it8rmh$6is$1@dont-email.me> (permalink)
References <it83e6$u4e$1@dont-email.me> <4df7a92f$0$12468$bed64819@gradwell.net> <it8n87$7rj$1@dont-email.me> <it8ps7$su3$1@dont-email.me>

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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.

-- 
Shelly

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Thread

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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