list of polymorphic objects

by

Your problem is called slicing and you should check this question: Learning C++: polymorphism and slicing

You should declare this list as a list of pointers to As:

list<A*> listOfAs;

and then insert these aB and aC pointers to it instead of creating copies of objects they are pointing to. The way you insert elements into list is wrong, you should rather use push_back function for inserting:

B bObj; 
C cObj;
A *aB = &bObj;
A *aC = &cObj;

listOfAs.push_back(aB);
listOfAs.push_back(aC);

Then your loop could look like this:

list<A*>::iterator it;
for (it = listOfAs.begin(); it != listOfAs.end(); it++)
{
    (*it)->say();
}

Output:

B Sayssss....
C Says

Hope this helps.

More Related Contents:

  1. c++ push reference node to stl list
  2. can a pure virtual function has parameters?
  3. Why do we need virtual functions in C++?
  4. vector vs. list in STL
  5. How are virtual functions and vtable implemented?
  6. Is list::size() really O(n)?
  7. Sort list using STL sort function
  8. Where do “pure virtual function call” crashes come from?
  9. Does std::list::remove method call destructor of each removed element?
  10. array vs vector vs list
  11. Cleaning up an STL list/vector of pointers
  12. C++: Why does a struct\class need a virtual method in order to be polymorphic?
  13. Why isn’t there an operator[] for a std::list?
  14. Store derived class objects in base class variables
  15. Why is it wrong to use std::auto_ptr with standard containers?
  16. Is it okay to inherit implementation from STL containers, rather than delegate?
  17. Using local classes with STL algorithms
  18. How do I print the elements of a C++ vector in GDB?
  19. std::string::c_str() and temporaries
  20. Run an Application in GDB Until an Exception Occurs
  21. What is the past-the-end iterator in STL C++?
  22. Can we use a user defined class for the key in a STL map?
  23. Are const_iterators faster?
  24. How to use the priority queue STL for objects?
  25. std::vector reserve() and push_back() is faster than resize() and array index, why?
  26. std::mutex performance compared to win32 CRITICAL_SECTION
  27. Visual c++ “for each” portability
  28. Is stl vector concurrent read thread-safe?
  29. Should you overload swap in the std namespace?
  30. Order Statistic Tree in C++

Leave a Comment