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: type [<ReferenceEquality; NoComparison>] FieldSpace =
      { CharacterOpt : Character Option
        PropOpt : PropType Option
        PickupItemOpt : PickupType Option }
  
      member this.GetCharacter =
          match this.CharacterOpt with Some character -> character | None -> failwithumf ()
  
negative.code:         chessboard.FieldSpaces.[coordinates].TryGetOccupant
      
      static member getPickup coordinates chessboard =
          chessboard.FieldSpaces.[coordinates].GetPickup
      
      // ignores non-adjacent enemies
      static member getNavigationMap currentCoordinates chessboard =
  