def page(record)
      p = @pages.get(record.page_idx, record) || load(record.page_idx, record)
      unless p.uid == record.page_idx
        raise RuntimeError, "Page reference mismatch. Record " +
          "#{record.page_idx} points to page #{p.uid}"
      end

      p
    end
def page(record)
      p = @pages.get(record.page_idx, record) || load(record.page_idx, record)
      unless p.uid == record.page_idx
        raise RuntimeError, "Page reference mismatch. Record " +
          "#{record.page_idx} points to page #{p.uid}"
      end

      p
    end
Return the IDListPage object with the given index.
 @param record [IDListPageRecord] the corresponding IDListPageRecord
 @return [IDListPage] The page corresponding to the index.