'->' and '-->' operators in TorqueScript

Could someone direct me to a good resource that explains what these (and other) operators do in TorqueScript? For some reason I've been having issues particularly with the '-->' operator in EditorGui::init in file EditorGui.ed.cs .

After I've executed this segment of code:

if( !isObject( %this-->ToolsPaletteWindow ) )
   {
      // Load Creator/Inspector GUI
      exec("~/worldEditor/gui/ToolsPaletteGroups/init.cs");
      exec("~/worldEditor/gui/ToolsPaletteWindow.ed.gui");
      
      if( isObject( EWToolsPaletteWindow ) )
      {
         %this.add( EWToolsPaletteWindow );
         EWToolsPaletteWindow.init();
         EWToolsPaletteWindow.setVisible( false );
      }
   }

isObject(%this-->ToolsPaletteWindow) still returns 0. I've changed this code to the code printed below (and changed all other relevant checks in other files) to fix the issue temporarily.

if( !isObject( %this.ToolsPaletteWindow ) )
   {
      // Load Creator/Inspector GUI
      exec("~/worldEditor/gui/ToolsPaletteGroups/init.cs");
      exec("~/worldEditor/gui/ToolsPaletteWindow.ed.gui");
      
      if( isObject( EWToolsPaletteWindow ) )
      {
         %this.add( EWToolsPaletteWindow );
         %this.ToolsPaletteWindow = EWToolsPaletteWindow;
         EWToolsPaletteWindow.init();
         EWToolsPaletteWindow.setVisible( false );
      }
   }