anchor.diff:    [Produces(TMediaType.APPLICATION_XML)]
     TDataSetWriterXML = class(TInterfacedObject, IMessageBodyWriter)
       procedure WriteTo(const AValue: TValue; const AMediaType: TMediaType;
  +      AOutputStream: TStream; const AActivation: IMARSActivation);
  +    class procedure WriteDataSet(const ADataSet: TValue; const AMediaType: TMediaType;
         AOutputStream: TStream; const AActivation: IMARSActivation);
     end;
   
  
positive.code: ;
  
  { TDataSetWriterJSON }
  
  procedure TDataSetWriterJSON.WriteTo(const AValue: TValue; const AMediaType: TMediaType;
    AOutputStream: TStream; const AActivation: IMARSActivation);
  
negative.code:   TDataSetWriterJSON = class(TInterfacedObject, IMessageBodyWriter)
      procedure WriteTo(const AValue: TValue; const AMediaType: TMediaType;
        AOutputStream: TStream; const AActivation: IMARSActivation);
      class procedure WriteDataSet(const ADataSet: TValue; const AMediaType: TMediaType;
        AOutputStream: TStream; const AActivation: IMARSActivation);
    end;
  
    [Produces(TMediaType.APPLICATION_JSON)]
  