Question

If you have an NSSet with objects of type car.
Car has two properties: NSString *name, NSInteger speed
You want an NSSet containing only NSStrings for the car names.

How can I do this without iterating over every object and putting it in a mutable set?

Answer 1

You can use key value coding.

NSSet *namesOfCars = [setOfCars valueForKeyPath:@"name"];