Patrick,

I don't really know if I am right, because of lack of experience. Please, 
correct me if I'm wrong, but... Why would anyone write code like that?

I mean, if one subclasses NSObject and doesn't override +init, it will return 
self -- or, maybe, nil -- anyways.

So, I would assume that [super init] would only be called inside an +init or 
+initWithWhatever: method, right? Like this:

+ (id*)init
{
        [super init];
        // initialize some other instance vars, etc. ...
        [return self];
}

So, in case a class' +init method can return nil and you want to subclass it, 
the code should be more like:

+ (id*)init
{
        if ([super init] != nil)
        {
                ...
                [return self];
        }
        else
        {
                return nil; // or return something else, throw an exception, 
whatever...
        }
}

I am just curious, because I think it's strange to write "self = [super init]" 
anywhere other than in an overriden +init. Am I right?


Cheers,
Flavio


On 08/05/2010, at 01:23, Patrick M. Rutkowski wrote:

> Will NSObject's init method ever really return nil?
> 
> E.g. if I sub-class NSObject, then is it worth checking for nil after
> doing self = [super init]?
> 
> I know there are many classes in UIKit and Cocoa which most definitely
> can return nil from their -init's, as an indication of failure. But
> will this ever be the case with NSObject?
> 
> -Patrick

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