                     if let error = operation.error
                     {
                         strongSelf.activityIndicatorView.stopAnimating()
-                        strongSelf.presentOperationErrorAlert(error)
+                        strongSelf.presentOperationErrorAlert(with: error)
                     }
                     else
                     {

        }
        else if let error = operation?.error
        {
            self.presentOperationErrorAlert(error)
        }
        else
        {

    
    // MARK: UI Presentation
    
    private func presentOperationErrorAlert(with error: NSError)
    {
        let alert = UIAlertController(title: "Operation Error", message: error.localizedDescription, preferredStyle: UIAlertControllerStyle.alert)
        alert.addAction(UIAlertAction(title: "Cancel", style: UIAlertActionStyle.default, handler: { [weak self] (action) -> Void in
