[boost] Re: [program_options] simple question

From: Neal Becker (ndbecker2_at_[hidden])
Date: 2004-03-25 22:04:01

OK, I found the answer to my (stupid) question --- I had to relearn how to
use program_options.

Which brings us to a IMHO really cool little example, combining lambda with
program_options:

,----[ /home/nbecker/boost-program_options/Test1.cc ]
| #include <boost/program_options.hpp>
| #include <iostream>
| #include <cxxabi.h>           // demangle
| #include <cmath>
| 
| using namespace std;
| namespace po = boost::program_options;
| 
| #include <boost/lambda/lambda.hpp>
| using namespace boost::lambda;
| 
| int main (int argc, char** argv) {
|   double angle;
| 
|   std::set_terminate(__gnu_cxx::__verbose_terminate_handler);
|   po::options_description desc("Allowed options");
|   desc.add_options()
|     ("help", "produce help message")
|     ("angle", po::value<double>()->notifier(var(angle)=180./M_PI*_1), "set
|     angle") ;
| 
|   po::variables_map vm;
| 
|   po::store(po::parse_command_line(argc, argv, desc), vm);
| 
| 
|   po::notify(vm);
| 
|   if (vm.count("help")) {
|     cout << desc << "\n";
|     return 1;
|   }
| 
|   cout << "angle: " << angle << '\n';
| }
`----