anchor.diff:              World.publish6 { Participant = entity; PropertyName = propertyName; OldWorld = oldWorld } changeEventAddress eventTrace entity false world
   
           static member private getEntityStateOpt entity world =
  -            World.entityStateFinder 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
  
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:                     if  entityState.Cachable &&
                          Xtension.getImperative entityState.Xtension then
                          entity.EntityStateOpt <- entityStateOpt
                      entityState
                  | None -> Unchecked.defaultof<EntityState>
              | Some entityState -> entityState
  
          static member private entityStateAdder entityState entity world =
              let screenDirectory =
  