get_one_gem_name

# File lib/rubygems/command.rb, line 206
  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