Re: [Boost-users] program options: unrecognized command-line options

Subject: Re: [Boost-users] program options: unrecognized command-line options
From: Deane Yang (deane.yang_at_[hidden])
Date: 2009-01-14 20:54:48

Christoph Duelli wrote:
> Deane Yang wrote:
> 
>> I'm using the program options library to parse both command-line and
>> configuration file parameters. I'd like to know how to find command-line
>> arguments that are *not* registered and therefore not recognized by the
>> parser. I want to be able to print a warning message like "Following
>> arguments were ignored:....".
> 
> I did it like that:
> 
> // assume that options is a std::vector<std::string> containing
> // the passed options (argv[])
>  po::options_description desc; // contains the options your prog supports
> 
> 
>  po::variables_map vm;
>  po::command_line_parser parser(options).allow_unregistered().options(desc);
> 
>  po::parsed_options parsed = parser.run();
>  po::store(parsed, vm);
>  po::notify(vm); // recognized options
> 
>  std::vector<std::string> unrecognizedOptions =
>    po::collect_unrecognized(parsed.options, po::include_positional);
> 
> 
> This is documented at
> doc/html/program_options/howto.html#id3458178 in your Boost docs.
> 

Thanks. I did see this, but was hoping for something more graceful. I 
find it ironic that to disallow unregistered options, I have to use the 
function allow_unregistered. Shouldn't the opposite of 
"allow_unregistered" be a state where unregistered options are forbidden?

Deane