anchor.diff:                      if  entityState.Cachable &&
                           Xtension.getImperative entityState.Xtension then
                           entity.EntityStateOpt <- entityStateOpt
  -                    entityStateOpt
  -                | None -> None
  -            | entityStateOpt -> entityStateOpt
  +                    entityState
  +                | None -> Unchecked.defaultof<EntityState>
  +            | Some entityState -> entityState
   
           static member private entityStateAdder entityState entity world =
               let screenDirectory =
  
positive.code:             let entityStateOpt = UMap.tryFind entity.EntityAddress world.EntityStates
              ((entity.EntityAddress, world.EntityStates), entityStateOpt)
  
          static member private entityStateFinder entity world =
              match entity.EntityStateOpt with
              | None ->
                  let entityStateOpt =
  
negative.code:             World.publish6 { Participant = entity; PropertyName = propertyName; OldWorld = oldWorld } changeEventAddress eventTrace entity false world
  
          static member private getEntityStateOpt entity world =
              let entityState = World.entityStateNullableFinder entity world
              if refEq entityState Unchecked.defaultof<EntityState> then None else Some entityState
  
          static member private getEntityState entity world =
  #if DEBUG
              match World.getEntityStateOpt entity world with
              | Some entityState -> entityState
              | None -> failwith ^ "Could not find entity with address '" + scstring entity.EntityAddress + "'."
  #else
              World.entityStateNullableFinder entity world
  #endif
  
          static member private setEntityState entityState entity world =
              World.entityStateSetter entityState entity world
  