anchor.diff:              | Some entityState -> entityState
               | None -> failwith ^ "Could not find entity with address '" + scstring entity.EntityAddress + "'."
   #else
  -            World.entityStateNullableFinder entity world
  +            World.entityStateFinder entity world
   #endif
   
           static member private setEntityState entityState entity world =
  
positive.code:                             | Some entityState -> entityState
                      entityState
                  | None -> Unchecked.defaultof<EntityState>
              else entityStateOpt
  
          static member private entityStateAdder entityState entity world =
              let screenDirectory =
  
negative.code:             let entityStateOpt = UMap.tryFind entity.EntityAddress world.EntityStates
              ((entity.EntityAddress, world.EntityStates), entityStateOpt)
  
          static member private entityStateFinder entity world =
              let entityStateOpt = entity.EntityStateOpt
              match entityStateOpt :> obj with
              | null ->
                  let entityStateOpt =
                      KeyedCache.getValue
                          World.entityStateKeyEquality
  