Recursive function to preload array of PFObjects

gistfile1.txt

    /**
     Recusivly pre load an array of PFObjects.
     
     - parameter items:      The items to preload.
     - parameter completion: Invoked once all loading in the background has been completed. If an error occured it will be passed back otherwise `success` will be `true` with a `nil` error parameter.
     */
    func preloadItems(items: [PFObject], completion: (success: Bool, error: NSError?) -> ()) {
        
        func recursiveLoad(index: Int) {
            
            if index == items.count {
                completion(success: true, error: nil)
                return
            }
            
            items[index].fetchInBackgroundWithBlock({ (object, error) in
                
                if let err = error {
                    completion(success: false, error: err)
                    return
                }
                else {
                    recursiveLoad(index + 1)
                }
            })
        }
        
        recursiveLoad(0)
    }