Re: Re[4]: KVC bug

[Richard Frith-Macdonald]

On Wednesday, February 27, 2002, at 03:06 PM, Manuel Guesdon wrote:

> > | So, if you build with just GNUstep-base, you get the Apple Foundation
> > | behavior, and if you
> > | build with GNUstepWeb/EOF you get the Apple webobjects behavior.
> > |
> > | Of course, we should test this - but methods in categories *should*
> > | override the methods
> > | in the original class.
>
> My god !
>
> This really means that *just*  linking or not with EOF (explicitely or 
> just because it's in the Makefile.preamble copied
> from somewhere) will change the behaviour of valueForKey: for 
> dictionary ? Or even different objective C library (I
> don't know where/how the category override is done).

This is standard behavior for categories - as each category is loaded at 
runtime,
it overrides existing behaviors.

> I think some people will have great moments trying to debug this. Let's 
> imagine a general bundle or a library for computing some
> stats, wich can be used with or without EOF. A thing as simple as 
> valueForKey:@"count" may return a
> different result. I imagine a discussion between a user of this bundle 
> and the developper:
> - the user, I've fund some problem.
> - the developper, could you provide me some small test code ?
> - the user: here is one but, eh !,  now it seems to work
> - the developper: could you rebuild your entire projects, it should work
> - the user: this still don't work but the test code works...
> ....
>
> I know the problem come initialy from Apple's API but couldn't we use 
> my code and your code with a "Strict MacOSX API
> compatible" #ifdef to select your code ? I generaly like compatibility 
> but not if this potentially mean completely
> strange problems and hours or days of debugging

I'd suggest using a warning log if the non-macos action is taken
ie if we handle count etc specially.

> Just for confirmation, you say your code is correct because you've made 
> a test or because cacoa documentation say
> nothing about these special keys ?

I tested it on MacOS-X