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Subject: Re: [boost] Boost and auto_ptr (was Boost 1.60.0 beta 1...)
From: Jonathan Wakely (jwakely.boost_at_[hidden])
Date: 2015-11-11 16:08:43

On 11 November 2015 at 01:17, Edward Diener wrote:
> I believe one is allowed to say that Y does everything that X does and is
> better and therefore X will be removed at some time in the future. If one
> cannot say that then computer programming will never advance to the use of
> better programming idioms. I don't believe that one must carry the baggage
> of X forever because some programmers want to use X in perpetuity.

Yes, well said.

> This is a general reflection and is not a specific argument for
> std::unique_ptr versus std::auto_ptr. However technically std::unique_ptr
> appears to me to be a superior programming idiom than std::auto_ptr and
> while I am not going to argue over a date in which std::auto_ptr should no
> longer be part of the C++ standard library, it seems inevitable to me that
> at some time in the future it would be removed from the C++ standard
> library.

It has already been removed from the current C++ working paper (what
will be C++17).

That doesn't mean implementors have to stop providing it, it only
means it is no longer defined by the standard. Supporting older
versions of the standard and users who mix old and new code is the
implementors job, it doesn't need to be supported by the C++17
standard. The C++17 standard defines C++17, not

If you have important reasons to keep using std::auto_ptr in modern
code then convince your standard library vendor to keep providing it.

(Although in this case I think using Boost's own unique_ptr makes far
more sense than throwing a hissy fit because a widely-misused class
has been removed. The C++ committee regularly gets criticised for too
much backwards compatibility, so while one angry person on the
internet is annoyed the first time a deprecated feature is actually
removed there are probably far more people saying "at last!!!").

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