Roel wrote:

Hi,

I've been using boost::program_options but I have some questions about it.

First: to catch errors that the users makes when specifying command-line options (eg I declared an option to be integer-only but the user specified a string), I surrounded the call to store() by a try/catch block:

try { boost::program_options::store( boost::program_options::command_line_parser(argc, argv). options(desc).positional(p).run(), vm); } catch (boost::program_options::invalid_option_value e) { }

But now how do I give a meaningfull error message? The what() function of invalid_option_value is private, what other options do I have?

You can use top-level try-block in main that catches std::exception. That will catch all possible errors, and not just specific 'invalid_option_value'. However, non-accessible 'what' is still a bug. I've fixed this, and will commit as soon as Sourceforce's CVS is operational agian.

Secondly, is there a mechanism to check the relation between options? I have a number of options: -a, -m and -d for add, modify and delete respectively; I want only one of them to be allowed at the same time. Also, when the -a option is specified, the -t and -r options are valid, and only then. Do I have to check all of that manually? Thanks.

I'm afraid this is not supported at the moment. - Volodya