Please Help - Brain Block

Using Xcode 12.5.1

I have 2 properties on an object

@property NSMutableArray *mutA1;
@property NSMutableArray *mutA2;

During initialization I do this:

self.mutA1 = [NSMutableArray arrayWithCapacity:10];
self.mutA2 = [NSMutableArray arrayWithCapacity:10];

The first assignment works fine but I get an error on the second assignment!

Exception	NSException *	"[<__NSArrayM 0x6000037f1ec0> addObserver:forKeyPath:options:context:] is not supported. Key path: count"	0x00006000037d74e0

What can explain this? I am just stumped!!

Thank you for any help! Steve

Does it happen on a new, single view project?

the answer is embedded in the exception text "...Key path: count".

I had somehow turned On a xib binding to "mutA2.count". Removing this cleared up the matter

Please Help - Brain Block
 
 
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