anchor.diff:          fieldSpace.ContainsProp
       
       member this.ContainsPickup =
  -        match this.PickupItemOpt with Some _ -> true | None -> false
  +        match this.PickupOpt with Some _ -> true | None -> false
       
       static member containsPickup (fieldSpace : FieldSpace) =
           fieldSpace.ContainsPickup
  
positive.code:     static member updatePropOpt updater fieldSpace =
          { fieldSpace with PropOpt = updater fieldSpace.PropOpt }
      
      static member updatePickupItemOpt updater fieldSpace =
          { fieldSpace with PickupItemOpt = updater fieldSpace.PickupItemOpt }
      
      static member updateCharacterInternal updater characterOpt =
          match characterOpt with
  
negative.code:         Map.toListBy (fun _ (v : FieldSpace) -> v.GetCharacterIndex) this.EnemySpaces
      
      member this.Pickups =
          Map.map (fun _ (v : FieldSpace) -> v.GetPickup) this.PickupSpaces
      
      member this.EnemyCount =
          this.EnemySpaces.Count
  