anchor.diff:              match out.Latest with
               | Failure _ -> ()
               | Success xs -> Array.iter add xs
  -            addStream.Subscribe(function
  +            adder.stream.Subscribe(function
                   | Failure _ -> ()
                   | Success init -> add init)
               |> ignore
               c.Container
   
  -        member this.Add = addStream :> Writer<'a>
  +        member this.Add = adder.stream :> Writer<'a>
   
           member this.AddRender f = adder.view f
   
  
positive.code: 
          inherit Reader<'a[]>(out.Id)
  
          let addStream = Stream<_>(Failure [])
  
          let streams = ResizeArray<Stream<'a>>()
  
          let update() =
  
negative.code:                 streams
              |> Result.Map (List.rev >> Array.ofList)
              |> out.Trigger
  
  
          override this.Subscribe f = out.Subscribe f
  