Re: [Boost-users] boost program options and notifier call

From: Vladimir Prus (vladimir_at_[hidden])
Date: 2008-07-30 13:17:48

Aljaz wrote:

> Hello
> 
> I have boost.program_options implemented inside a config class.
> 
> I want to call function (my_function) that is a member of config class for
> specific option (with notifier call).
> 
> class config_class {
> public:
>  void read_config() {
>   po::options_description desc("Allowed options");
>   desc.add_options()
>    ("help", "produce help message")
>    ("include-path,I", po::value< vector<string>
>  >()->notifier(&config_class::my_function),  "include path");
>  }
> 
>  void my_function(vector<std::string> str) {  }

Don't pass vector by value. Further, the notifier method is documented
thusly:

        typed_value * notifier(function1< void, const T & > f) ;
        Specifies a function to be called when the final value is determined.

So you better make the parameter const -- you won't be able to modify it
anyway.

> };
> 
> 
> This wont compile and will give error for
> ..>()->notifier(&config_class::my_function)...
>  >> error C2064: term does not evaluate to a function taking 1 arguments
> 
> What am I doing wrong?

You are passing function with two parameters ("this" and "str") where a function
taking one parameter is expected. Use:

        boost::bind(&config_class::my_function, this)

- Volodya