[Boost-bugs] [Boost C++ Libraries] #8775: fusion transform and fold not respecting const-ness of the sequence

Subject: [Boost-bugs] [Boost C++ Libraries] #8775: fusion transform and fold not respecting const-ness of the sequence
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2013-07-03 21:14:48

#8775: fusion transform and fold not respecting const-ness of the sequence
-------------------------------------+---------------------
 Reporter:  eric_niebler             |      Owner:  djowel
     Type:  Bugs                     |     Status:  new
Milestone:  To Be Determined         |  Component:  fusion
  Version:  Boost Development Trunk  |   Severity:  Problem
 Keywords:                           |
-------------------------------------+---------------------
 The following does not compile:

 {{{
 #include <boost/fusion/include/vector.hpp>
 #include <boost/fusion/include/transform.hpp>
 #include <boost/fusion/include/fold.hpp>
 #include <boost/fusion/include/copy.hpp>
 namespace fusion = boost::fusion;

 struct F
 {
     typedef int result_type;
     int operator()(int state, int & val) const
     {
         return state;
     }
 };

 struct G
 {
     typedef int result_type;
     int operator()(int & val) const
     {
         return val;
     }
 };

 int main()
 {
     fusion::vector<int, int> v(1,2);
     fusion::vector<int, int> v2;
     // fold does not respect constness
     fusion::fold(v, 42, F());
     // transform does not respect constness
     fusion::copy(fusion::transform(v, G()), v2);
 }
 }}}

 In my opinion, it should.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/8775>
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