Objective C Blocks: Is there a way to avoid saving the self?

Question

I try to write it as concisely as possible, but it is not easy to describe - so thanks for reading =)

I am the main developer of the Open Source iPhone Framework Sparrow . Sparrow is modeled after the Flash AS3 Library and thus has an event system similar to AS3. This system currently works by specifying a selector, but I would like to expand this system by allowing the use of blocks for event listeners. However, I run into memory management issues.

I will show you a typical case of using events, since they are now being processed.

// init-method of a display object, inheriting from 
// the base event dispatcher class
- (id)init
{
    if (self = [super init])
    {
        // the method 'addEventListener...' is defined in the base class
        [self addEventListener:@selector(onAddedToStage:)
                      atObject:self
                       forType:SP_EVENT_TYPE_ADDED_TO_STAGE];
    }
    return self;
}

// the corresponding event listener
- (void)onAddedToStage:(SPEvent *)event
{
    [self startAnimations]; // call some method of self
}

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- (id)init
{
    if (self = [super init])
    {
        // [self addEventListener: ...] would somehow cause:
        [self retain]; // (A)
    }
    return self;
}

// the corresponding event listener
- (void)dealloc
{
    // [self removeEventListener...] would cause:
    [self release]; // (B)
    [super dealloc];
}

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- (id)init
{
    if (self = [super init])
    {
        [self addEventListenerForType:ADDED_TO_STAGE block:^(SPEvent *event)
        {
            [self startAnimations];
        }];
    }
    return self;
}

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__block id blockSelf = self;
[self addEventListenerForType:ADDED_TO_STAGE block:^(SPEvent *event)
{
    [blockSelf startAnimations];
}];

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Answer 1

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[self addEventListenerForType:ADDED_TO_STAGE 
                        block:^(id selfReference, SPEvent *event)

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Answer 2

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