NSArray Equivalent of Map

Question

Given an NSArray of NSDictionary objects (containing similar objects and keys) is it possible to write perform a map to an array of specified key?

Answer 1

I've no idea what that bit of Ruby does but I think you are looking for NSArray's implementation of -valueForKey:. This sends -valueForKey: to every element of the array and returns an array of the results. If the elements in the receiving array are NSDictionaries, -valueForKey: is nearly the same as -objectForKey:. It will work as long as the key doesn't start with an @