Re: [Boost-bugs] [Boost C++ Libraries] #973: zip_iterator has value_type == reference

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #973: zip_iterator has value_type == reference
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2012-12-02 08:18:41

#973: zip_iterator has value_type == reference
---------------------------+------------------------------------------------
  Reporter:  anonymous     |       Owner:  jeffrey.hellrung
      Type:  Bugs          |      Status:  new             
 Milestone:                |   Component:  iterator        
   Version:  Boost 1.34.0  |    Severity:  Problem         
Resolution:                |    Keywords:                  
---------------------------+------------------------------------------------

Comment (by Matthias Berndt <matthias_berndt@…>):

 You're right, it's not as trivial as it seemed. Applying the patch fixes
 the reference/value semantics, but it breaks the iterator's operator->.
 iterator_facade's operator-> assumes that taking a reference's address
 yields something convertible to value_type*. I'm not sure what this
 assumption is based upon; I can't see anything in the
 [[http://www.boost.org/doc/libs/1_52_0/libs/iterator/doc/new-iter-

 concepts.html#forward-traversal-iterators-lib-forward-traversal-
 iterators|New Iterator Concepts]] that justifies this assumption, but I
 may have missed something.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/973#comment:12>
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