Re: [Boost-users] weak_from_this

Subject: Re: [Boost-users] weak_from_this
From: Frank Mori Hess (frank.hess_at_[hidden])
Date: 2010-08-10 20:46:38

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On Tuesday 10 August 2010, Hite, Christopher wrote:
> shared_from_this contains a weak_ptr.  Why not implement a weak_from_this()
> member function?
>
> Upgrading and downgrading a shared_ptr costs expensive atomic ops.  I've
> got some setup code that just gives weak_ptr's to
> boost::singals2::slot::track().
>
> Is this a valid (and simple) feature request?

There is a boost/smart_ptr/enable_shared_from_raw.hpp which has a 
weak_from_raw() free function.  Unfortunately, I never got around to 
documenting enable_shared_from_raw or trying to get it merged to release.  
The main difference from enable_shared_from_this is that 
enable_shared_from_raw is not a template class (no curiously recurring 
template pattern), and shared_from_raw()/weak_from_raw() are free template 
functions that take an argument instead of being member functions.  Also, 
they can be used in constructors (although it can be dangerous to do so if 
you're not careful).

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