# File lib/aws/xml_grammar.rb, line 376
      def validate_args(identifier, args)
        arity = method(identifier).arity
        if args.length > 0
          raise "#{identifier} does not accept an argument" if
            arity == 0
        else
          raise "#{identifier} requires an argument" unless
            arity == 0 || arity == -1
        end
      end