# File lib/rubygems/command.rb, line 76
    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