override  func viewDidLoad() {
    super .viewDidLoad()

}

func showOkay (){
 let title = NSLocalizedString("a title", comment: "")
 let message = NSLocalizedString("msg", comment: "")
 let cansal = NSLocalizedString("cancel", comment: "")
 let ok = NSLocalizedString("ok", comment: "")
 let alertController = UIAlertController (title: title, message: message, preferredStyle: .alert)

    let cancelAlertAction = UIAlertAction (title : cansal , style : .cancel) {
        _ in print("cancel") \ i don't understand this line . its just a print or somthing else . why i cant use print here.
    }
    let okAction = UIAlertAction(title: ok , style : .default){
       _ in print("ok") \ i don't understand this line. its just a print or somthing else. why i cant use print here.
    }

    alertController.addAction(cancelAlertAction)
    alertController.addAction(okAction)
    present(alertController ,animated: true , completion: nil)
}
@IBAction func btnAction(_ sender: Any) {
     showOkay()
}