get_one_gem_name (Gem::Command)

    # File lib/rubygems/command.rb, line 166
      def get_one_gem_name
        args = options[:args]

        if args.nil? or args.empty? then
          raise Gem::CommandLineError,
                "Please specify a gem name on the command line (e.g. gem build GEMNAME)"
        end

        if args.size > 1 then
          raise Gem::CommandLineError,
                "Too many gem names (#{args.join(', ')}); please specify only one"
        end

        args.first
      end