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Ho hum,

I was wondering how you can go about sending a message to a super->super class? I need to decode something with NSCoder, but must call the objects [super->super initWithCoder:coder], and not the super’s. The [super->super call] and super super] call] do not work. Aside: how can I send a message to a specific class in the hierarchy? In C++ you could make sure that specific method implementations were called like this: [[BaseClassName::MemberFunc(Args); So how do I do this in Objective-C?

You can use +[NSObject instanceMethodForSelector:] to retrieve a particular method implementation. That addresses both of your questions. However, you should not do this as a matter of course. You ought to have a really special situation on your hands before you think about doing this.

Why don’t you want to call [super initWithCoder:]? I bet there’s a better solution than what you’re going for. “Unfourtunately not, this hack is necessary to make an old C api cocoa friendly. Thanks for the help”

Also, thinking of super as an object isn’t a good idea. super is a keyword. [self someMethod] is equivalent to objc_msgSend(self, @selector(someMethod)) while [super someMethod] is equivalent to objc_msgSendSuper(super-context, someMethod). Insofar as super is an object, it’s the same object as self.

Another way of doing this would be to add the call to your super’s super as a method of your super, via a category:

@implementation MySuperClass (BypassRedefinedCoderCategory) -(id) initUsingSuperclassImplementationWithCoder:(NSCoder *)coder
return [super initWithCoder:coder];
} @end

// Somewhere in your code self = [super initUsingSuperclassImplementationWithCoder:coder]

I assume your subclass is primarily trying to alter the superclass’ use of coders?