                 let value = asciiEscape(utf8Decode(data))
                 mutableRequest.addValue(value, forHTTPHeaderField: "Dropbox-Api-Arg")
             }
-            
+
             return (mutableRequest, nil)
         }))
     }
-    
-    /// Called as the upload progresses. 
+
+    /// Called as the upload progresses.
     ///
     /// :param: closure
     ///         a callback taking three arguments (`bytesWritten`, `totalBytesWritten`, `totalBytesExpectedToWrite`)

    case RateLimitError
    case HTTPError(Int?, String?)
    case RouteError(Box<ErrorType>)
    
    
    public var description : String {
        switch self {
        case .InternalServerError(let code, let message):

        self.request.progress(closure: closure)
        return self
    }

    /// Called when a request completes.
    ///
    /// :param: completionHandler
    ///         A callback taking two arguments (`response`, `error`) which handles the result of the call appropriately.
    /// :returns: The request, for chaining purposes.
    public func response(completionHandler: (RType.ValueType?, CallError<EType.ValueType>?) -> Void) -> Self {
        self.request.validate().response {
            (request, response, dataObj, error) -> Void in
            let data = dataObj as NSData!
            if error != nil {
                completionHandler(nil, self.handleResponseError(response, data: data))
            } else {
