so, if you type --location canada, the code should store the supplied string - canada and pass it on to the program. This is a typical program option with nothing special. But I cannot seem to get it to work!
Please look at this:
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std::string place_option; // a global variable
po::options_description general("General options");
general.add_options()
("location", po::value<std::string>(), "location of your home");
// there are other non string options
po::variables_map vm;
po::store(po::parse_command_line(ac,av, general),vm);
po::notify(vm);
if(vm.count("help"))
{
std::cout << general << "\n";
return 0;
}
if(vm.count("version, v"))
{
std::cout << "version aplha\n";
}
if(vm.count("location"))
{
place_option = vm["location"].as<std::string>();
// should pass the string value entered at command line to std::string place.
}
If i run my program with eg 'myprogram --location disney'
I get:
terminate called after throwing an instance of 'std::logic_error'
what(): basic_string::_S_construct NULL not valid
Aborted
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Now I have tried a few variations of the code. The examples show where an int value is supplied and retrieved. I cannot work out how to do - what should be very trivial. I simply want to recover the value associated with 'location' i.e a std::string entered at the command line. I then want to pass that value on to my program to do something with it. I do not understand the error. Can someone kindly show me the correct syntax to accomplish this please?
Kind regards.