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Re: Programming it's a play
From: |
Pascal J . Bourguignon |
Subject: |
Re: Programming it's a play |
Date: |
Sun, 21 Sep 2003 16:00:35 +0200 |
Pete French writes:
> > I do want to know what this means. Can someone that writes a class, like
> > the Greeter example write his own Class methods or are Class methods
> > just inherited from the root class. Meaning you can only add instance
> > methods.
>
> You can add your own class or instance methods as you like. As long as you
> bear in mind that yopu are adding them to a completely different object to the
> instance methods.
>
> > What is your view on a class (remember I am a VERY newbie). How can you
> > send a message to a class when a class is not an object.
>
> A class *is* an object - whos primary purpose is to create other objects.
> trying to make a distinction between the written description and the
> compiled version (which you seem to be trying to do) is only going
> to confuse things.
>
> Its not often that you want to send a message to a class, other than
> 'alloc' (or 'new' for alloc] init]). The acting school example muddies
> the waters a lot if you try and over-extend it to include class objects.
> Thats the trouble with all metaphors to try and explain OOP as theres
> nothing in the real world which operates in exactly the same way...
Note however, that you could use classes instead of singleton
instances, with the only downside in Objective C that class attributes
must be normal C static variables.
Note also that when you send a message to something, you don't precise
if it's a class message or an instance message; eeing only:
[foo doBar];
you cannot say if doBar is an instance method or a class method, (it's
none, it is a message!), or if foo refers a class or an object (a
class IS an object so it does not matter).
--
__Pascal_Bourguignon__
http://www.informatimago.com/
Do not adjust your mind, there is a fault in reality.
- Re: Programming it's a play, (continued)
- Re: Programming it's a play, Edward Dore, 2003/09/20
- Re: Programming it's a play, Nicolas Roard, 2003/09/20
- Re: Programming it's a play, Dennis Leeuw, 2003/09/20
- Re: Programming it's a play, Nicolas Roard, 2003/09/20
- Re: Programming it's a play, Pascal J . Bourguignon, 2003/09/20
- Re: Programming it's a play, Dennis Leeuw, 2003/09/21
- Re: Programming it's a play, Pete French, 2003/09/21
- Re: Programming it's a play, Dennis Leeuw, 2003/09/21
- Re: Programming it's a play, Pete French, 2003/09/21
- Re: Programming it's a play,
Pascal J . Bourguignon <=
- Re: Programming it's a play, Dennis Leeuw, 2003/09/21
- Re: Programming it's a play, Pascal J . Bourguignon, 2003/09/21
- Re: Programming it's a play, Pascal J . Bourguignon, 2003/09/21
Re: Programming it's a play, Pascal J . Bourguignon, 2003/09/21
Re: PATCH: Merge objc-improvements-branch to mainline, Ziemowit Laski, 2003/09/24
Re: PATCH: Merge objc-improvements-branch to mainline, Dietmar Planitzer, 2003/09/25