# File lib/rack/deflater.rb, line 60
      def each(&block)
        @writer = block
        gzip  =::Zlib::GzipWriter.new(self)
        gzip.mtime = @mtime
        @body.each { |part|
          gzip.write(part)
          gzip.flush
        }
      ensure
        @body.close if @body.respond_to?(:close)
        gzip.close
        @writer = nil
      end