[Boost-bugs] [Boost C++ Libraries] #7418: Copyable and explicitly movable classes

Subject: [Boost-bugs] [Boost C++ Libraries] #7418: Copyable and explicitly movable classes
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2012-09-24 22:19:11

#7418: Copyable and explicitly movable classes
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 Reporter:  danieljames       |       Owner:  igaztanaga
     Type:  Feature Requests  |      Status:  new       
Milestone:  To Be Determined  |   Component:  move      
  Version:  Boost 1.52.0      |    Severity:  Problem   
 Keywords:                    |  
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 Making a class movable can have some unfortunate side effects, as far as I
 know these are all due to implementing implicit moves. So if possible,
 it's be useful to have a class where the move mechanism only kicks in when
 boost::move is explicitly used. This could be efficient for cases where
 the class is explicitly moved (e.g. in a move enable vector), but avoid
 the potential problems.

 I believe that this could be done by defining just the move construct and
 move assignment, but with no implicit conversions or other special
 functions. Then the main difficultly is modifying the
 `has_move_emulation_enabled` trait to support these types. Maybe the class
 could have a magic member typedef which is detected by sfinae, or maybe
 you can come up with something better.

 Does this sound like a good idea? I haven't tried implementing it, so I
 might be missing some problem with the idea.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/7418>
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