[Boost-bugs] [Boost C++ Libraries] #7526: zip_iterator does not support std::tuple and std::pair

Subject: [Boost-bugs] [Boost C++ Libraries] #7526: zip_iterator does not support std::tuple and std::pair
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2012-10-18 10:05:27

#7526: zip_iterator does not support std::tuple and std::pair
-------------------------------------------------+--------------------------
 Reporter:  claas.koehler@…                      |       Owner:  dave    
     Type:  Feature Requests                     |      Status:  new     
Milestone:  To Be Determined                     |   Component:  iterator
  Version:  Boost 1.50.0                         |    Severity:  Problem 
 Keywords:  zip_iterator, std::tuple, std::pair  |  
-------------------------------------------------+--------------------------
 The boost zip_iterator is not compatible with std::tuple and std::pair

 The proposed patch solves this problem.

 Note that I copied some more general tuple algorithms I created for
 another project. These are all included in the newly introduced namespace
 helper. Maybe they can be rewritten using boost::mpl, but since I am not
 familiar with it I used the existing code.

 Furthermore I encountered the problem, that a specialisation of the
 template functions in namespace  tuple_impl_specific does not work, if
 this is done outside zip_iterator.hpp. The reason appears to be, that the
 user overloads are not known to the compiler, when the functions are
 called. This may be a problem, if users want to specialise for their own
 tuple class. To overcome this difficulty, I replaced the template
 functions by template classes, which seem to work even if specialisations
 are made outside zip_iterator.hpp

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/7526>
Boost C++ Libraries <http://www.boost.org/>
Boost provides free peer-reviewed portable C++ source libraries.