Re: [boost] [any] last commit breaks program_options

Subject: Re: [boost] [any] last commit breaks program_options
From: Jürgen Hunold (jhunold_at_[hidden])
Date: 2013-04-15 09:27:32

Hi Antony,

On Monday, 15. April 2013 13:19:26 Antony Polukhin wrote:
> 2013/4/15 Jürgen Hunold <jhunold_at_gmx.eu>:
> > Hi!
> > 
> > It seems that introducing move semantics to Boot.Any in r 83901 breaks
> > compilation of program_options.
> > 
> > /home/hunold/src/devel/boost/boost/program_options/variables_map.hpp:58:38
> > :
> > note:   no known conversion for argument 1 from
> > ‘boost::program_options::variable_value’ to
> > ‘boost::program_options::variable_value&’
> > 
> > Full build log attached.
> > 
> > Any Ideas?
> 
> This looks like Boost.Move known limitation:
> http://www.boost.org/doc/libs/1_53_0/doc/html/move/emulation_limitations.htm
> l#move.emulation_limitations.assignment_operator

Thanks. Clang had a better diagnostic, so I figured out I had to implement 
operator= (patch attached) to get this working. 

> I'm afraid that this will confuse a lot of people who use Boost.Any...
> May be it would be better to disable ravlue emulation and use rvalues
> only in C++11?

I'm only using ProgramOptions at the moment. And not following the move 
discussion for pre-c++11 not closely enough to comment on this. C++11 only 
support for be enough for me.

My 0.02€.

Yours,

Jürgen
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