[Boost-bugs] [Boost C++ Libraries] #3175: compilation error about fusion::traits::tag_of using msvc 8.0

Subject: [Boost-bugs] [Boost C++ Libraries] #3175: compilation error about fusion::traits::tag_of using msvc 8.0
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2009-06-15 09:22:41

#3175: compilation error about fusion::traits::tag_of using msvc 8.0
-----------------------------------------------------+----------------------
 Reporter:  Tang Jiang Jun <tangjiangjun_at_[hidden]>  |       Owner:  djowel 
     Type:  Bugs                                     |      Status:  new    
Milestone:  Boost 1.40.0                             |   Component:  fusion 
  Version:  Boost 1.39.0                             |    Severity:  Problem
 Keywords:  tag_of is_sequence                       |  
-----------------------------------------------------+----------------------
 I met a compilation error about matching the proper tag_of metafunction.
 The code snippet is shown as follow.

 #include <boost/fusion/support.hpp>
 #include <boost/fusion/container.hpp>
 #include <boost/fusion/sequence.hpp>
 #include <boost/fusion/algorithm.hpp>

 #include <string>
 #include <iostream>

 using namespace std;
 using namespace boost;

 int _tmain(int argc, _TCHAR* argv[])
 {
         typedef fusion::vector< int, char, string > VecTuple;
         VecTuple stuff( 1, 'a', "Hello, fusion!" );

         cout << stuff << endl;
         return 0;
 }

 The error message is:
 1>e:\libraries\boost_1_37_0\boost\fusion\support\is_sequence.hpp(59) :
 error C2039: 'tag_of' : is not a member of 'boost::fusion::traits::detail'
 1>        e:\libraries\boost_1_37_0\boost\utility\enable_if.hpp(36) : see
 reference to class template instantiation
 'boost::fusion::traits::is_sequence<T>' being compiled
 1>        with
 1>        [
 1>            T=VecTuple
 1>        ]
 1>        e:\samples\boost\fusion\fusion.cpp(52) : see reference to class
 template instantiation 'boost::enable_if<Cond,T>' being compiled
 1>        with
 1>        [
 1>            Cond=boost::fusion::traits::is_sequence<VecTuple>,
 1>            T=std::ostream &
 1>        ]

 I found that if adding the full namespace 'boost::fusion' before
 '::detail::tag_of' in the file 'is_sequence.hpp', everything will be OK.
 So I think that maybe is a namespace lookup error in msvc.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/3175>
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