# File lib/archive/zip/codec/deflate.rb, line 190
    def initialize(general_purpose_flags = NORMAL)
      @compression_level = general_purpose_flags & 0b110
      @zlib_compression_level = case @compression_level
                                when NORMAL
                                  Zlib::DEFAULT_COMPRESSION
                                when MAXIMUM
                                  Zlib::BEST_COMPRESSION
                                when FAST
                                  Zlib::BEST_SPEED
                                when SUPER_FAST
                                  Zlib::NO_COMPRESSION
                                else
                                  raise Error, 'Invalid compression level'
                                end
    end