Abstract class,interface

[Kostya Khuta]

Hello. I have some problem.
I have interface with 2 function


class Convert{
virtual string ob_to_str(Convert *)=0;
virtual Convert* str_to_ob(string s)=0;
};

then i have next class

class A:public Convert{

How to convert String to Object??
How to convert object to String???


}

[vlad from moscow]

I would declare function ob_to_str the following way

virtual string ob_to_str() const = 0;

and define it in the derived class as

string A::ob_to_str() const
{
   return ( "A" );
}

[LB]

struct Object
{
    Object(std::string s)
    {
        //instantiate from string
    }

    operator std::string()
    {
        return ""; //convert to string
    }
};

Unfortunately an interface cannot easily require sub-classes to expose a public constructor with a specific signature.