anchor.diff:              StateBuilder = stateBuilder
               Validators = List.empty
               Handler = f >> Seq.singleton
  -            Process = (fun cmd -> EventStream.eventStream { 
  -                return NonEmptyList.singleton "todo" |> Failure
  -            })
           } : CommandHandler<'TCmd, 'TState, 'TId, 'TEvent> 
   
       let toChoiceValidator cmd r =
  
positive.code:             new ICommandHandler<'TState,'TEvent,'TId> with 
                   member this.GetId cmd = untypedGetId sb cmd
                   member this.CmdType = typeof<'TCmd>
                   member this.Process cmd = sb.Process (cmd :?> 'TCmd)
                   member this.Handler cmd stream =
                      let unwrapper = MagicMapper.getUnwrapper<'TEvent>()
                      eventStream {
  
negative.code:     StateBuilder : StateBuilder<'TState>
      Validators : Validator<'TCmd,'TState> list
      Handler : 'TCmd -> seq<'TEvent>
  }
  
  open Eventful.EventStream
  