Use of unresolved identifier (accessing values)

I have this class:

class AlamofireService {


static let alamofireService = AlamofireService()


private init() {

}

internal func makePostServiceRequest(url: String, parameters: AnyObject, completed: RequestComplete) -> RestResponse {

    let restResponse = RestResponse()

    Alamofire.request(.POST, URL_BASE, parameters: [IOS_PARAMS : parameters], encoding:.JSON).validate()
        .responseJSON

        {
            response in switch response.result
            {
            case .Success(let JSON):
                print("Success with JSON: \(JSON)")

                restResponse.success = true
                restResponse.JSONString = JSON as? String


                let response = JSON as! NSDictionary
                print(response)



                var array = NSMutableArray!()
                array = response.valueForKey("countryList") as? NSMutableArray


            case .Failure(let error):
                print("Request failed with error: \(error)")
                restResponse.success = false
                restResponse.error = error.localizedFailureReason
                restResponse.responseCode = error.code

            }
    }
    return restResponse

}
}

And when i'm trying to call the function with this code:

AlamofireService.alamofireService.makePostServiceRequest(URL_BASE, parameters: params!) { () -> () in

        if (restResponse.succes == true){
            let user = Mapper<User>().map(restResponse.JSONString)
            print(user?.username)
            self.performSegueWithIdentifier("tabBarIdentifier", sender: nil)
        }

        print("Something went wrong")
    }



    }

I get the error from the title on 3th and 4th line. I don't understand why i can't access it.

Even if i have a closure which allows me to call the block of code after makePostServiceRequest is done, it suppose that i can use the restResponse constant.

I need something that will help me to know whether is the case successful or not, but out of function with switch statement