Inserting different types of objects into one queue

[ray]

Hi,
I wish to place objects of class B and class C into one queue. The queue, say class Queue, is a class template. Further, B and C are derived from class A. Can I say something like:

Queue<A> qobject;
B bob;
C cat;
qobject.insert(bob);
qobject.insert(cat);

or do I have to cast objects of B and C to type A before insertion. If so how do I cast objects from one type to another at run time.
Also, if the above is possible how do I, when removing objects from the queue, know which type of object I am removing.

I would be grateful for all help

[jonnin]

I would make a union or a class with pointers to all the classes and make a Q of that.

[nspils]

couldn't you "cast" them at time of creation of the objects?

A* bob = new Bob;
A* cat = new Cat;

now the object pointer is of the supertype A but are constructed as objects of the child classes .. and they can be added to the queue ...

[Danny]

Actually, what you're looking for is a heterogeneous conatiner. I discussed it recently:
http://www.devx.com/cplus/10MinuteSolution/29757
The pointer cast option is applicable only if you a hierarchy of classes, i.e., B is derived from C