Lorenzo Bettini <bettini@dsi.unifi.it> writes:
Jonathan Wakely wrote:
On Mon, Jun 06, 2005 at 03:58:41PM +0200, Lorenzo Bettini wrote:
However, it is not clear to me how to use weak_ptr in this context...
can some one provide some clue, please? Well, for this context: class C; typedef boost::shared_ptr<C> CP; typedef boost::weak_ptr<C> WP; class C { private: string s; WP wp; public: C(const string &ss, CP c = CP()) : s(ss), wp(c) {} void set(CP c) { wp = c; } ~C() { cout << "destroying C" << endl; } }; Then main() would be unchanged. That might not work for anything less trivial than your example, since you'd need to ensure the shared_ptrs that own the objects are still around when you use the weak_ptrs.
indeed, it only works for that simple main: the main problem I had is just "ensure the shared_ptrs that own the objects are still around when you use the weak_ptrs.".
Moreover, I had to deal with mutual dependences, and this makes the whole thing worse...
Can you deal with deallocation of the whole network at once? It often works to maintain the nodes (C objects) in a container like a deque and let them link to one another with raw pointers. Otherwise you may be in need of a real GC. -- Dave Abrahams Boost Consulting www.boost-consulting.com