protected override void CollectVolatileData_Custom()
 {
     this.m_data.Clear();
     List <GH_ValueListItem> .Enumerator enumerator = this.SelectedItems.GetEnumerator();
     try
     {
         Bool6D result = new Bool6D();
         while (enumerator.MoveNext())
         {
             GH_ValueListItem item  = enumerator.Current;
             Direction        value = (Direction)Enum.Parse(typeof(Direction), item.Expression);
             result = result.With(value, true);
         }
         this.m_data.Append(new Bool6DGoo(result), new GH_Path(0));
     }
     finally
     {
         ((System.IDisposable)enumerator).Dispose();
     }
 }