>  The standard C++ vector<> container is almost perfect for use in Perl
 >  arrays and the data stack.  But it has a major weakness...  It's _so_
 >  general that it doesn't use memcpy() [or moral equivalent] when it has
 >  to grow.  Instead, it uses copy constructors in a loop.  That could be
 >  a major performance issue with vector<Counted_p<T>>.
 
 Have you considered deque<> ? It doesn't copy the elements when
 growing.
 
 >  Now, I could write a vector<>
 
 Do you mean a vector_Counted_p<> ? Better create a partial
 specialization of vector<> :
 
         template<class T, class A> 
         class vector<Counted_p<T> , A>
         {
                 // ...
         };
 -- 
 Jean-Louis Leroy
 http://users.skynet.be/jll