Question

Hi all,

@property (nonatomic, assign) NSInteger myindex;

this line changes to unsafe_unretained after performing a convertion to Objective C ARC can any one please explain me regarding this.

Answer 1

In your case it won’t change to unsafe_unretained because it is a scalar value.
Probably you wrote like:

@property (nonatomic, assign) NSInteger *myindex; 

that’s why it is converting to unsafe_unretained.

In ARC assign is effectively unsafe_unretained.

For scalars values like int, float. You can use assign itself.
For objects you can use either weak or unsafe_unretained, it depends on the context.

unsafe_unretained and weak prevent the retention of objects, but in slightly different ways.

• weak the pointer to an object will convert to nil when the object is deallocated.
• unsafe_unretained will continue pointing to the memory where an object was, even after it was deallocated. This can lead to crashes due to accessing that deallocated object.