Question

Suppose I have something like this:

@property (readonly) NSMutableArray *someArray; 

Can I modify [obj someArray] even though the @property is set to readonly?

Answer 1

Yes, you can modify its contents. The readonly only applies to the pointer itself – in that way, it is not like C++’s const.

Basically, saying ‘readonly’ just means ‘don’t translate a.someArray = foo into [a setSomeArray:foo]‘. That is, no setter is created.

(Of course, if you wanted to prevent modification, you’d just use an NSArray instead.)