Putting the Parser and Scanner Together Now, it's a really simple task to put the parser and scanner together and let them do their work. Here, we simply create an instance of out scanner and parser classes. int main(int argc, char** argv) { std::string file; getargs(argc, argv, file); if (argc > 1) return 0; simple_scanner s; simple_parser p(s); And finally, we put the parser to work by invoking the parse member function return p.parse(0); }