Exception thrown in NSOrderedSet generated accessors

Question

On my Lion app, I have this data model:

The relationship subitem

Answer 1

I have the same situation with an item called "signals" instead of "subitems". The solution with tempset works in my testing. Further, I had a problem with the removeSignals: method. This override seems to work:

- (void)removeSignals:(NSOrderedSet *)values {
    NSMutableOrderedSet* tempset = [NSMutableOrderedSet orderedSetWithOrderedSet:self.signals];
    for (Signal* aSignal in values) {
        [tempset removeObject:aSignal];
    }
    self.signals = tempset;
}

If there is a better way to do this, please let me know. My values input is never more than 10 -20 items so performance isn't much of a concern - nonetheless please point out anything relevant.

Thanks,

Damien