def child_cell(index)
      assert_exists

      if (index - Celerity.index_offset) >= @cells.length
        raise UnknownCellException, "Unable to locate a cell at index #{index}"
      end

      TableCell.new(self, :object, @cells[index - Celerity.index_offset])
    end
def child_cell(index)
      assert_exists

      if (index - Celerity.index_offset) >= @cells.length
        raise UnknownCellException, "Unable to locate a cell at index #{index}"
      end

      TableCell.new(self, :object, @cells[index - Celerity.index_offset])
    end
Get the child cell at the given index