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

From: Aljaz (aljaz.fajmut_at_[hidden])
Date: 2008-07-30 13:49:16

Thanks a lot for help!

I have no idea why the following code crashes my MSVC optimizing compiler:

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(boost::bind(&config_class::my_function, this)),  "include 
path");
    }

    void my_function(vector<std::string> str) {
    }

};

Any idea?

"Vladimir Prus" <vladimir_at_[hidden]> wrote in message 
news:g6q7o4$v7h$1_at_ger.gmane.org...
> 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