anchor.diff:  
   // create and send response for the request here.
   // if you are using Future or Stream objects inside of the try block,
  -// you have to handle their error and throw that error.
  -void requestReceivedHandler(HttpRequest request) {
  +// you have to catch their error and throw that error as an Exception.
  +void service(HttpRequest request) {
     try {
  -//  var x = 1 % 0;  // uncomment this line to test exception handling
  +//  throw new Exception('exception raised');  // uncomment this line to test exception handling
       String htmlResponse = createHtmlResponse();
       sendResponse(request, htmlResponse);
     }
  
positive.code:             "from ${request.connectionInfo.remoteAddress}");
            }
            if (request.uri.path == REQUEST_PATH) {
              requestReceivedHandler(request);
            }
            else request.response.close();
          });
  
negative.code: // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
  // for details. All rights reserved. Use of this source code is governed by a
  // BSD-style license that can be found in the LICENSE file.
  // December 2013, Modified by Terry.
  // Access this server as 'http://localhost:8080/time'.
  
  import "dart:io";
  import "dart:convert";
  