anchor.diff:                SubResId = subResId
                 OwinContext = owinContext }
       
  +    type NoBody() = 
  +        inherit DtoBase()
  +        override __.Validate() = ok()
  +    
       type ResponseContext<'T> = 
           | SomeResponse of responseBody : Choice<'T, Error> * successCode : HttpStatusCode * failureCode : HttpStatusCode
           | SuccessResponse of responseBody : 'T * successCode : HttpStatusCode
  
positive.code:             match response with
              | Choice1Of2(r) -> owinContext |> this.SerializeSuccess r successStatus
              | Choice2Of2(r) -> owinContext |> this.SerializeFailure r failureStatus
          
          member __.SetDefaults(value : 'T) = 
              match defaultValueSetter with
              | Some(func) -> func (value)
              | _ -> value
          
          abstract Process : request:RequestContext * body:'T option -> ResponseContext<'U>
      
  
negative.code:     let execute (request : RequestContext, handler : HttpHandlerBase<_, _>) = 
          let validateRequest() = 
              maybe { 
                  let! body = match handler.HasBody with
                              | true -> 
                                  match handler.DeSerialize(request.OwinContext.Request) with
                                  | Choice1Of2 a -> ok <| Some(a)
                                  | Choice2Of2 b -> 
                                      if handler.FailOnMissingBody then fail <| b
                                      else ok <| None
                              | false -> ok <| None
                  /// Validate the DTO
                  if body.IsSome && handler.ValidateBody then do! body.Value.Validate()
                  return body
              }
          
  