anchor.diff:          with get () = bufferDict.flatten()
           and set b = bufferDict.unflatten(b)
   
  +    /// <summary>TBD</summary>
       member _.state
           with get () = stateDict
           and set s = stateDict.set(s)
   
  +    /// <summary>TBD</summary>
       member _.stateVector
           with get () = stateDict.flatten()
           and set s = stateDict.unflatten(s)
  
positive.code:     /// <summary>Gets the number of parameters of the model</summary>
      member m.nparameters = m.parameters.nelement
  
      member m.nbuffers = m.buffers.nelement
  
      member m.nstate = m.state.nelement
  
      member _.children
          with get () = 
              modelDict.Values |> Seq.cast<ModelBase> |> Seq.toList
  
      member m.models
          with get () =
              m :: [for c in m.children do yield! c.models]
  
      member m.hasOwnParameters
          with get () =
              let childrenParams = m.children |> List.map (fun c -> c.nparameters) |> List.sum
              m.nparameters <> childrenParams
  
      member m.hasOwnBuffers
          with get () =
              let childrenBuffers = m.children |> List.map (fun c -> c.nbuffers) |> List.sum
              m.nbuffers <> childrenBuffers
  
      member m.hasOwnState
          with get () =
              let childrenState = m.children |> List.map (fun c -> c.nstate) |> List.sum
  
negative.code:         sb.Append(")") |> ignore
          sb.ToString()
  
      /// <summary>TBD</summary>
      member m.summary() =
          let sb = System.Text.StringBuilder()
          sb.AppendLine("---") |> ignore
  