let manager = AFHTTPRequestOperationManager()

        let url = "http://api.openweathermap.org/data/2.5/weather"

        let params = ["lat": latitude, "long": longitude, "cnt": 0]

        manager.GET(url,

            parameters: params,

            success: { (operation:AFHTTPRequestOperation!,

                responseObject: AnyObject!) in

                print("JSON: " + responseObject.description!)

            },

            failure: { (operation:AFHTTPRequestOperation!,

                error: NSError!) in

                print("Error: " + error.localizedDescription)

        })

failure里提示/Users/enchanterzero/Desktop/1/Weather/Weather/ViewController.swift:52:22: Cannot convert value of type '(AFHTTPRequestOperation!, NSError!) -> _' to expected argument type '((AFHTTPRequestOperation?, NSError) -> Void)?'