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() ) { ... }