    # File lib/supplemental/facets/argvector.rb, line 220
      def parse_line(line=nil)
        if line
          case line
          when String
            argv = Shellwords.shellwords(line)
          else
            argv = line.to_ary.dup
            line = argv.join(' ')
          end
        else
          argv = ARGV.dup
          line = argv.join(' ')
        end
        return line, argv
      end