anchor.diff:              | Some(treeView) -> treeView :> Widget
               | None ->
                   let treeStore = new TreeStore(typedefof<obj>)
  -                let padTreeView = new PadTreeView(treeStore)
  +                let padTreeView = new PadTreeView(treeStore, HeadersVisible = true)
   
                   let setCellIcon (_) (cellRenderer : CellRenderer) (treeModel : TreeModel) (iter : TreeIter) =
                       let pixRenderer = cellRenderer :?> CellRendererImage
  
positive.code: 
                  treeView <- Some padTreeView
  
                  let pixRenderer = new CellRendererImage()
                  pixRenderer.Xpad <- 0u
                  pixRenderer.Ypad <- 0u
                  padTreeView.TextRenderer.Xpad <- 0u
                  padTreeView.TextRenderer.Ypad <- 0u
  
  
negative.code:                 treeCol.SetCellDataFunc(padTreeView.TextRenderer, new TreeCellDataFunc(setCellText))
  
                  padTreeView.AppendColumn treeCol |> ignore
                  padTreeView.Realized.Add(fun _ -> refillTree |> ignore)
                  padTreeView.Selection.Changed.Subscribe(fun _ -> jumpToDeclaration false) |> ignore
                  padTreeView.RowActivated.Subscribe(fun _ -> jumpToDeclaration true) |> ignore
  