Thanks, that did it. It's not intuitive, and not obvious from the documentation.

-----Original Message----- From: boost-bounces@lists.boost.org [mailto:boost-bounces@lists.boost.org] On Behalf Of Michael B. Edwin Rickert Sent: Wednesday, August 03, 2005 3:14 PM To: boost@lists.boost.org Subject: Re: [boost] weak_ptr, maybe empty

Andy Thomas-Cramer wrote:

...

I have a weak_ptr that might be empty. If not empty, I'd like to make a smart pointer from it.

But the code below throws in the shared_ptr constructor, and I don't see how to test whether a weak_ptr is empty.

boost::weak_ptr<int> wp; boost::shared_ptr<int> sp(wp); if ( sp.get() ) { ... }

The documentation (http://boost.org/libs/smart_ptr/weak_ptr.htm) seems to show a few options. The most similar to your situation would be:

boost::weak_ptr< int > wp; boost::shared_ptr< int > sp = wp.lock(); if ( sp.get() ) { ... } _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost