anchor.diff:                  if Keys.Control = Control.ModifierKeys && Keys.C = key then handleFormCopy form (EventArgs ())
                   if Keys.Control = Control.ModifierKeys && Keys.V = key then handleFormPaste false form (EventArgs ())
                   if Keys.Delete = key then handleFormDeleteEntity form (EventArgs ())
  +                if Keys.Escape = key then deselectEntity form world
   
       let private handleFormClosing (_ : GaiaForm) (args : CancelEventArgs) =
           match MessageBox.Show ("Are you sure you want to close Gaia?", "Close Gaia?", MessageBoxButtons.OKCancel) with
  
positive.code:         not form.editWhileInteractiveCheckBox.Checked
  
      let private tryMousePick (form : GaiaForm) mousePosition world =
          let (entities, world) = getPickableEntities world
          let pickedOpt = World.tryPickEntity mousePosition entities world
          match pickedOpt with
          | Some entity ->
              selectEntity form entity world
              (Some entity, world)
          | None -> (None, world)
  
      let private handleNuChangeParentNodeOpt form _ world =
          refreshHierarchyTreeView form world
  
negative.code:             if Keys.Alt = Control.ModifierKeys && Keys.T = key && form.rolloutTabControl.SelectedTab.Name = "eventTracingTabPage" then form.traceEventsCheckBox.Checked <- not form.traceEventsCheckBox.Checked
              if Keys.Alt = Control.ModifierKeys && Keys.V = key && form.rolloutTabControl.SelectedTab.Name = "evaluatorTabPage" then form.evalButton.PerformClick ()
              if Keys.Alt = Control.ModifierKeys && Keys.L = key && form.rolloutTabControl.SelectedTab.Name = "evaluatorTabPage" then form.evalLineButton.PerformClick ()
              if not isKeyFromKeyableControl then
                  if Keys.Control = Control.ModifierKeys && Keys.A = key then handleFormSave true form (EventArgs ())
                  if Keys.Control = Control.ModifierKeys && Keys.Z = key then handleFormUndo form (EventArgs ())
                  if Keys.Control = Control.ModifierKeys && Keys.Y = key then handleFormRedo form (EventArgs ())
  