Re: [boost] [unordered] a strange limitation for move emulation in Boost.Unordered

Subject: Re: [boost] [unordered] a strange limitation for move emulation in Boost.Unordered
From: Daniel James (daniel_at_[hidden])
Date: 2013-07-08 08:38:55

On 8 July 2013 13:25, Joaquin M Lopez Munoz <joaquin_at_[hidden]> wrote:
> Daniel James <daniel <at> calamity.org.uk> writes:
>
>>
>> On 8 July 2013 09:17, Joaquin M Lopez Munoz <joaquin <at> tid.es> wrote:
>> > Here:
>> >
>> >
> http://www.boost.org/doc/html/unordered/compliance.html#unordered.compliance.move
>> >
>> > it reads:
>> >
>> > "Non-copyable objects can be stored in the containers, but without
>> > support for rvalue references the container will not be movable."
>> >
>> > Why not? Container movement does not ever touch its elements, so I
>> > don't see the connection.
>>
>> Using move emulation caused some problems:
>>
>> https://svn.boost.org/trac/boost/ticket/6167
>> https://svn.boost.org/trac/boost/ticket/6311
>>
>
> Yes, but these problems have nothing to do with whether the
> *elements* of the container are copyable or not, right?

Oh, you've misread the documentation. Perhaps it is a bit ambiguous.
I'll change it to:

* Non-copyable objects can be stored in the containers.
* Without support for rvalue references the container will not be movable.
* Argument forwarding is not perfect.