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Subject: Re: [boost] [variant] Basic rvalue and C++11 features support
From: Andrey Semashev (andrey.semashev_at_[hidden])
Date: 2013-01-11 09:55:29

On Friday 11 January 2013 08:47:42 Larry Evans wrote:
> On 01/11/13 08:18, Peter Dimov wrote:
> I was thinking that after the move to the target variant, the source
> variant has its tag reset to something to indicate the current type is
> this default constructable type and that type would be empty. IOW,
> a default contructable something like:
> special_type<nothing_id>
> found here:
> orage/special_components.hpp

I vaugly remember that variant had a special support for type boost::blank
that could be used as a fallback type for some operations. So if the variant
has this type in the list of possible types the move operation could leave the
source with boost::blank value. But that would only work if boost::blank was
in the list.

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