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Re: NSObject description not working

On Fri, 30 Jan 2004 02:33:16 -0500, Eric Wang <email@hidden> said:
>on 1/10/04 11:20 PM, matt neuburg at email@hidden wrote:
>
>> The following code shows the problem. The first two
>> parts are just warm-up, to show what *should* happen.
>> The third part is the problem.
>>
>> MyObject* obj = [[MyObject alloc] init];
>> NSLog([obj description]); // "howdy"
>>
>> NSArray* arr = [NSArray arrayWithObject: obj];
>> [obj release];
>> obj = [arr objectAtIndex: 0];
>> NSLog([obj description]); // "howdy"
>> NSLog([[obj class] description]); // "MyObject"
>>
>> NSLog([[theList objectAtIndex: 0] description]); // "<MyObject:0x387ef0>"
>> NSLog([[[theList objectAtIndex: 0] class] description]); // "MyObject"
>>
>> In the next-to-last line, instead of executing the
>> description method and returning "howdy", the object
>> returns this thing in angle-brackets. Yet it is a
>> MyObject, just as before. So why is this?
>>
>> The only difference that seems relevant is that theList
>> is populated and maintained by an NSArrayController /
>> NSObjectController. But how could this be relevant? If a
>> thing is a MyObject instance, shouldn't it respond to a
>> MyObject instance method, no matter how it was created?
>> m.
>
>
>It seems that when using bindings, a class that is being observed
>is replaced by a custom subclass NSNotifying_YourClassNameHere at runtime.
>That subclass implements -description to print out the object address, thus
>overriding your class's description method,

Is this worth a bug report? Personally I would prefer a MyObject to behave
like a MyObject, not like some other object merely because an
NSArrayController put it into the array... m.
--
matt neuburg, phd = email@hidden, http://www.tidbits.com/matt/
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