anchor.diff:                         [Content.sidebar (v2 24.0f 417.0f) 1.0f field
                           Content.items (v2 138.0f 417.0f) 1.0f 10 5 field MenuItemSelect
                           Content.text Gen.name
  -                           [Entity.PositionLocal == v2 368.0f 3.0f; Entity.ElevationLocal == 1.0f
  +                           [Entity.PositionLocal == v2 399.0f 24.0f; Entity.ElevationLocal == 1.0f
                               Entity.Justification == Justified (JustifyCenter, JustifyMiddle)
                               Entity.Text <== field --> (fun field -> string field.Inventory.Gold + "G")]
                           Content.button Gen.name
                             [Entity.PositionLocal == v2 138.0f 12.0f; Entity.ElevationLocal == 1.0f; Entity.Size == v2 72.0f 72.0f
                              Entity.Text == "<"
  +                           Entity.VisibleLocal <== field --> fun field -> Content.pageItems 10 field |> a__
                              Entity.UpImage == Assets.Gui.ButtonSmallUpImage
                              Entity.DownImage == Assets.Gui.ButtonSmallDownImage
                              Entity.ClickEvent ==> msg MenuItemsPageUp]
                           Content.button Gen.name
  -                          [Entity.PositionLocal == v2 804.0f 12.0f; Entity.ElevationLocal == 1.0f; Entity.Size == v2 72.0f 72.0f
  +                          [Entity.PositionLocal == v2 777.0f 12.0f; Entity.ElevationLocal == 1.0f; Entity.Size == v2 72.0f 72.0f
                              Entity.Text == ">"
  +                           Entity.VisibleLocal <== field --> fun field -> Content.pageItems 10 field |> _b_
                              Entity.UpImage == Assets.Gui.ButtonSmallUpImage
                              Entity.DownImage == Assets.Gui.ButtonSmallDownImage
                              Entity.ClickEvent ==> msg MenuInventoryPageDown]]
  
positive.code:     [<RequireQualifiedAccess>]
      module Content =
  
          let private pageItems pageSize pageIndex filter sort (items : Map<ItemType, int>) =
              items |>
              Map.toSeq |>
              (fun items -> if filter then ItemType.filterSellableItems items else items) |>
              (fun items -> if sort then ItemType.sortItems items else items) |>
              Seq.index |>
              Seq.chunkBySize pageSize |>
              Seq.trySkip pageIndex |>
              Seq.map List.ofArray |>
              Seq.tryHead |>
              Option.defaultValue [] |>
              Seq.indexed |>
              Map.ofSeq |>
              Map.map (fun _ (i, (item, count)) -> (i, (item, Some count)))
  
          let sidebar position elevation (field : Lens<Field, World>) =
              Content.association Gen.name []
  
negative.code: 
          let items (position : Vector2) elevation rows columns field fieldMsg =
              Content.entities field
                  (fun (field : Field) _ -> pageItems rows field |> __c)
                  (fun i selectionLens _ ->
                      let x = if i < columns then position.X else position.X + 375.0f
                      let y = position.Y - single (i % columns) * 81.0f
  