anchor.diff:        }
         f.openRead().pipe(response).catchError(onError);
       });
  +  }
  +
  +  void compileToJavaScript(Uri dartScript) {
  +    Uri outputUri = request.uri;
  +    print("Compiling $dartScript to $outputUri");
  +    // TODO(ahe): Implement this.
  +    notFound(request.uri);
     }
   
     static onRequest(HttpRequest request) {
  
positive.code:     }
      String path = uri.path;
      Uri root = documentRoot;
      String dartType = 'application/dart';
      if (path.startsWith('${PACKAGES_PATH}/')) {
        root = packageRoot;
        path = path.substring(PACKAGES_PATH.length);
      }
  
      String filePath = root.resolve('.$path').toFilePath();
      switch (request.method) {
        case 'GET':
          return handleGet(filePath, dartType);
        default:
          String method = const HtmlEscape().convert(request.method);
          return badRequest("Unsupported method: '$method'");
      }
    }
  
    void handleGet(String path, String dartType) {
      var f = new File(path);
      f.exists().then((bool exists) {
        if (!exists) return notFound(request.uri);
        if (path.endsWith('.html')) {
          response.headers.set(CONTENT_TYPE, 'text/html');
        } else if (path.endsWith('.dart')) {
          response.headers.set(CONTENT_TYPE, dartType);
        } else if (path.endsWith('.js')) {
          response.headers.set(CONTENT_TYPE, 'application/javascript');
        } else if (path.endsWith('.ico')) {
  
negative.code:   }
  
    notFound(path) {
      response.headers.set(CONTENT_TYPE, 'text/html');
      response.statusCode = HttpStatus.NOT_FOUND;
      response.write(htmlInfo('Not Found',
                              'The file "$path" could not be found.'));
  