anchor.diff:  import 'dart:async';
   import 'package:route/server.dart';
   import 'package:static_file_handler/static_file_handler.dart';
  -
   
   typedef void HttpRequestHandler(HttpRequest request);
   
  
positive.code:     _defaulHttpHeaders.add({'name': name, 'value': value});
    }
  
  
    void addView(Pattern url,HttpRequestHandler handler) {
      router.serve(url).listen((HttpRequest httpRequest) {
        if (_defaulHttpHeaders != null) {
  
negative.code:     router.defaultStream.listen(handler);
    }
  
    Future listen() {
      print("Starting HTTP server");
      return HttpServer.bind(host, port).then((HttpServer server) {
  