How can I use covariant return types with smart pointers?

Question

I have code like this:

class RetInterface {...}

class Ret1: public RetInterface {...}

class AInterface
{
  public:
     virtual boost::shared_ptr

        

Answer 1

maybe you could use an out parameter to get around "covariance with returned boost shared_ptrs.

 void get_r_to(boost::shared_ptr& ) ...

since I suspect a caller can drop in a more refined shared_ptr type as argument.