Re: [Boost-bugs] [Boost C++ Libraries] #7630: Range adaptors do not play nicely with range-based for loops

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #7630: Range adaptors do not play nicely with range-based for loops
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2013-05-01 15:58:16

#7630: Range adaptors do not play nicely with range-based for loops
--------------------------------+-------------------------------------------
  Reporter:  gromer@…           |       Owner:  neilgroves
      Type:  Bugs               |      Status:  new       
 Milestone:  To Be Determined   |   Component:  range     
   Version:  Boost 1.51.0       |    Severity:  Problem   
Resolution:                     |    Keywords:  range     
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Comment (by gromer@…):

 One point of clarification, since it confused even me when I reread this:
 {{{operator |}}} is left-associative, so the adaptor expression is
 equivalent to {{{((vec | boost::adaptors::reversed) |
 boost::adaptors::uniqued)}}}. The temporary returned by the whole
 expression gets bound to {{{__range}}}, and therefore has its lifetime
 extended to match {{{__range}}}, but the temporary returned by the
 ''subexpression'' {{{vec | boost::adaptors::reversed}}} is not bound to a
 reference in the scope of the loop, so its lifetime is not extended.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/7630#comment:5>
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