ios - Does adding a NSMutableDictionary to a NSMutableDictionary make a copy or does it keep a pointer -

does adding nsmutabledictionary nsmutabledictionary make copy or keep pointer.

i want able update content of first nsmutabledictionary , have tracked within other nsmutabledictionary - example...

    nsmutabledictionary* dicta = [[nsmutabledictionary alloc] init];     nsmutabledictionary* dictb = [[nsmutabledictionary alloc] init];     [dicta setvalue:[nsnumber numberwithint:1 ] forkey:@"number"];     [dictb setvalue:dicta forkey:@"dicta"];      [dicta setvalue:[nsnumber numberwithint:2 ] forkey:@"number"]; 

will dictb.dicta.number = 2?

yes, will. in general, cocoa collection classes retain objects added them (the purpose: way can insert non-copyable objects too).

(with corefoundation trickery , toll-free bridging, possible realize nsarray copies elements, though.)