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Re: is protected broken, or am I?
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Re: is protected broken, or am I?


  • Subject: Re: is protected broken, or am I?
  • From: Brent Gulanowski <email@hidden>
  • Date: Fri, 11 Oct 2002 11:39:16 -0400

On Thursday, October 10, 2002, at 06:42 PM, matt neuburg wrote:


My idea was that I would connect the MySubClass instance to the MyClass instance, and then the MySubClass instance could see the window connections by way of the MyClass instance (because this is what I thought "protected" meant), and would also inherit the same functionality (because it's a subclass) and so would be able to keep what was applicable and override what was not.

Why can you not just initialize the subclass instance with the same ivar values that are in the MyClass instance? The subclass has all the ivars of the superclass and any new ones that you add. Or does the subclass instance in question have to muck about with more than one instance of the superclass? In which case, I suspect that you should have a controller object doing the work, be it a delegate or otherwise, and the ivars should be in there, not in MyClass or MySubClass at all.

The central idea of objects is that they cannot get into each others' ivars, even if they are of the exact same class. The exception to this is the friend construct in C++, and whatever it is you're saying REALBasic allows, where a declared friend class instance can read ivars of instances of the class in question. Objective-C doesn't allow this, prefering that you always use accessors. Is using accessors to get ivar values so much of a pain? Or do you have religious objections? Saying "I can do it in another language" is not a good argument.

The pattern that's becoming apparent is that, instead of learning how things are done in Objective-C, you are bringing your own concepts to the language and trying to make them work, then blaming the language when you can't. That is self-defeating. It is also why everyone is confused by your questions. They are alien to the design of the language and environment that their thinking automatically assumes when answering questions on a list like this.

Cheers,

--
Brent Gulanowski email@hidden

"We've heard that a million monkeys at a million keyboards could produce the Complete Works of Shakespeare; now, thanks to the Internet, we know this is not true." -- Robert Wilensky
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