The following code example is taken from the book
C++ Templates - The Complete Guide
by David Vandevoorde and Nicolai M. Josuttis, Addison-Wesley, 2002
© Copyright David Vandevoorde and Nicolai M. Josuttis 2002
template <typename T, typename CONT>
template <typename T2, typename CONT2>
Stack<T,CONT>&
Stack<T,CONT>::operator= (Stack<T2,CONT2> const& op2)
{
if ((void*)this == (void*)&op2) { // assignment to itself?
return *this;
}
Stack<T2,CONT2> tmp(op2); // create a copy of the assigned stack
elems.clear(); // remove existing elements
while (!tmp.empty()) { // copy all elements
elems.push_front(tmp.top());
tmp.pop();
}
return *this;
}