def compression_strategy(val = NULL)
      if null?(val)
        @compression_strategy
      else
        unless val.is_a?(Symbol) &&
            [:filtered, :huffman, :rle, :fixed, :extreme].member?(val)
          raise InvalidValue.new(:compression_strategy, "be a Symbol (:filtered, "\
                                                        ":huffman, :rle, :fixed, or :extreme)")
        end

        @compression_strategy = val
      end
    end
def compression_strategy(val = NULL)
      if null?(val)
        @compression_strategy
      else
        unless val.is_a?(Symbol) &&
            [:filtered, :huffman, :rle, :fixed, :extreme].member?(val)
          raise InvalidValue.new(:compression_strategy, "be a Symbol (:filtered, "\
                                                        ":huffman, :rle, :fixed, or :extreme)")
        end

        @compression_strategy = val
      end
    end
Compression strategy to use (-Z).
 For gzip: :filtered, :huffman, :rle, or :fixed;
 for xz: :extreme
 (nil means parameter will not be passsed to dpkg-deb)

 @example
   compression_strategy :extreme

 @param [Symbol] val
   compression strategy

 @return [Symbol]
   compression strategy for this package