# File lib/ole/storage/base.rb, line 310
    def repack temp=:file
      case temp
      when :file
        Tempfile.open 'ole-repack' do |io|
          io.binmode
          repack_using_io io
        end
      when :mem;  StringIO.open('', &method(:repack_using_io))
      else raise ArgumentError, "unknown temp backing #{temp.inspect}"
      end
    end