anchor.diff:              Address.hash this.GroupAddress
   
           interface Simulant with
  -            member this.SimulantAddress = atoa<Group, Simulant> this.GroupAddress
  +            member this.SimulantAddress = simulantAddress
               end
   
           interface Group IComparable with
  
positive.code:     and Entity (entityAddress) =
  
          // check that address is of correct length for an entity
          do if Address.length entityAddress <> 3 then
              failwith "Entity address must be length of 3."
  
          /// The entity's update event.
          let updateEvent =
  
negative.code:             Address.hash this.EntityAddress
  
          interface Simulant with
              member this.SimulantAddress = simulantAddress
              end
  
          interface Entity IComparable with
  