class Zip::Deflater

def <<(data)
  val   = data.to_s
  @crc  = Zlib.crc32(val, @crc)
  @size += val.bytesize
  buffer = @zlib_deflater.deflate(data)
  if buffer.empty?
    @output_stream
  else
    @output_stream << @encrypter.encrypt(buffer)
  end
end