Re: [boost] shared_ptr ordering

Subject: Re: [boost] shared_ptr ordering
From: Peter Dimov (lists_at_[hidden])
Date: 2013-04-22 15:32:30

Matt Bergin wrote:
> Back in 2008, changing shared_ptr operator< to compare by pointer value
> rather than owner was discussed:
> http://lists.boost.org/Archives/boost/2008/10/143175.php
>
> There seem to be convincing arguments for both implementations (aliasing,
> consistency with equality operator etc).
>
> Is boost::shared_ptr intended to be a compliant C++11 std::shared_ptr?

At this point, keeping the current, nonstandard, operator< no longer seems 
right. However, ...

>  If so, will shared_ptr be changed to comply with 
> [util.smartptr.shared.cmp] or is the ensuing breakage too high a price to 
> pay for 100% compliance?

... I wish there were a way to answer this question before just going 
forward with the change.

Either way, people who rely on the current meaning will consider the 
breakage unacceptable, and those who are not affected will consider it 
welcome.