Folks,

            What is the best way to pass a std::vector<boost::shared_ptr<Derived> > to a function that expects a std::vector<boost::shared_ptr<Base> >?

Can I use a cast or should I create a new std::vector<boost::shared_ptr<Base> > by iterating over the std::vector<boost::shared_ptr<Derived> >?

Here is some sample code. What f is doing is not important it is just an example:

class A { // This class is from a library I have no control over.

public:

virtual string getName() { return string("A");}

};

class B : public A  { // I need to create B from A to have extra functionality

public:

virtual string getName() { return string("B");}

       virtual string getLongName() { return string("This is B");}

};

void f(std::vector<boost::shared_ptr<A> > &v) {  // This function is from a library that I have no control over.

for(int i = 0; i < v.size(); i++)

              cout << v[i]->getName();

}

int main(char *argv, int arc) {

       std::vector<boost::shared_ptr<B> > bvec(10);

       boost::shared_ptr<B> bPtr(new B);

       bvec[0] = bPtr;

       f(bvec); // This should not compile. ß-----------------------

}

The last line (with the arrow) won’t compile because std::vector<boost::shared_ptr<B> > cannot be converted to std::vector<boost::shared_ptr<A> >.