[boost] [MPL] is_sequence problem

6 May 2005

      Hi,

I have a problem with this code snippet:

     #include <boost/mpl/is_sequence.hpp>

     int
     main()
     {
         using boost::mpl::int_;
         using boost::mpl::is_sequence;
         bool b = is_sequence<int_<0> >::value;
     }

VC7.1 complains:

C:\dev\boost\boost\mpl\aux_\begin_end_impl.hpp(35) : error C2039: 
'begin' : is not a member of 'boost::mpl::int_<N>'
         with
         [
             N=0
         ]
         C:\dev\boost\boost\mpl\begin_end.hpp(35) : see reference to 
class template instantiation 
'boost::mpl::begin_impl<Tag>::apply<Sequence>' being compiled
         with
         [
             Tag=boost::mpl::begin<boost::mpl::int_<0>>::tag_,
             Sequence=boost::mpl::int_<0>
         ]
         C:\dev\boost\boost\mpl\is_sequence.hpp(94) : see reference to 
class template instantiation 'boost::mpl::begin<Sequence>' being compiled
         with
         [
             Sequence=boost::mpl::int_<0>
         ]
         C:\dev\test\mpl_is_sequence.cpp(8) : see reference to class 
template instantiation 'boost::mpl::is_sequence<T>' being compiled
         with
         [
             T=boost::mpl::int_<0>
         ]
C:\dev\boost\boost\mpl\aux_\begin_end_impl.hpp(35) : error C2955: 
'boost::mpl::begin' : use of class template requires template argument list
         C:\dev\boost\boost\mpl\begin_end.hpp(38) : see declaration of 
'boost::mpl::begin'
C:\dev\boost\boost\mpl\begin_end.hpp(35) : error C2955: 
'boost::mpl::begin' : use of class template requires template argument list
         C:\dev\boost\boost\mpl\begin_end.hpp(38) : see declaration of 
'boost::mpl::begin'
C:\dev\boost\boost\mpl\is_sequence.hpp(94) : error C3203: 'begin' : 
class template invalid as template argument for template parameter 'T', 
expected a real type
...
Exit code: 2
Any hints? I am relying on is_sequence to return false in this case.
Comeau and g++ throws up too.

Regards,
-- 
Joel de Guzman
http://www.boost-consulting.com
http://spirit.sf.net