anchor.diff:      });
   
     pairs() =>
  -    fields.map((field) => serializerOverrides(field) ? readFromSerializer(field) : readFromModel(field));
  +    fields.map((_) => serializerOverrides(_) ? readFromSerializer(_) : readFromModel(_));
   
  -  readFromSerializer(field) =>
  -    new Future.immediate([field, serializer.custom[field](model)]);
  +  readFromSerializer(String field) =>
  +    new Future.value([field, serializer.custom[field](model)]);
   
  -  readFromModel(field) =>
  +  readFromModel(String field) =>
       reflect(model).
  -      getField(field).
  +      getFieldAsync(new Symbol(field)).
         then((v) => [field, v.reflectee]).
         catchError((e){throw new SerializerConfigurationError(model, field);});
   }
  
positive.code:     return serializer.postProcessing(withRoot, model);
    }
  
    serialize(){
      var res = fields.reduce({}, (Map res, String field) {
        if(serializerOverrides(field)){
          res[field] = readFromSerializer(field);
        } else {
          res[field] = readFromModel(field);
  
negative.code:     return postProcessing(res);
    }
  
    readFromSerializer(String field) => serializer.custom[field](model);
  
    readFromModel(String field) {
      var value = deprecatedFutureValue(reflect(model).getFieldAsync(new Symbol(field)));
  
      if (value is MirroredCompilationError) {
        throw new SerializerConfigurationError(model, field);
      }
      return value.reflectee;
  