Is heterogeneous container of boost::shared_ptr possible?

[rssmps]

Hi, first post and here it goes...

This is the current code (working) that I have. It works but for large number of A & B objects, it's not the most efficient. It's also not really heterogenous either. It's really just a storage of the parent class objects.

class A
{ … }
class B:public A
{ … }
 
vector<A*> combined;
vector<A> list_A;
vector<B> list_B;
for(size_t i=0; i<list_A.size();i++)
{
   combined.push_back(new A(list_A[i]));
}
for(size_t i=0; i<list_B.size();i++)
{
   combined.push_back(new B(list_B[i]));
}
 

So instead, I changed to using boost shared pointers for list_A and list_B.
Now, I still need to combined those two different vectos into a single one.
Something like this:

vector< boost::shared_ptr<A> > list_A;
vector< boost::shared_ptr<B> > list_B;
for(size_t i=0; i<list_A.size();i++)
{
   combined.push_back(list_A[i]);
}
for(size_t i=0; i<list_B.size();i++)
{
   combined.push_back(list_B[i]);
}
 

I’d like to do something like the above but I’m not sure how to define my
vector< … > combined;

Following the original method, I thought about:

vector<  boost::shared_ptr<A>  > combined; 
 

So how would I populate combined from list_B?
even though B inherits A, you can't just replace boost::shared_ptr<A> with boost::shared_ptr<B> directly right?

[weaknessforcats]

How does B inherit A ??

If there are no virtual functions in A, then you can have a vector<B>.
Otherwise you cannot since the virtual function in A indicates polymorphism and that indicates using base pointers or referecnes only.

Therefore, if A has a virtual function, then you can have a vector of shhared_ptr. Since all calls use the A interface there's nothing to combine. You put the B objects in the vector as shared_ptr<A>.