Re: [boost] Using weak_ptr with a hash

From: Greg Colvin (Gregory.Colvin_at_[hidden])
Date: 2003-03-07 21:16:02

What are you trying to do?

Usually weak_ptr is used as the value in a map with some other key, so
that just being in the map doesn't prevent an object from being deleted.

At 06:52 PM 3/7/2003, Joe Gottman wrote:
>   I just realized that it would be impossible to use weak_ptr with any
>hash.   The problem is that the hash function would have to use weak_ptr's
>get() method.  Then if the underlying object of the weak_ptr gets destroyed,
>get() will suddenly return 0 instead of the previous pointer, so the hash
>function will now map the weak_ptr to a new bucket.   Is there any way to
>add a member function that returns a const void * that will be invariant
>even if the underlying object of the weak_ptr has been destroyed?
>
>Joe Gottman
>
>
>
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