//Purpose:
//  Demonstrate fusion::map like template using 
//  multiple inheritance like that described for
//  _Tuple_impl here:
//
//    http://groups.google.com/group/comp.std.c++/msg/6449d909fd3d5cdc
//
//   fusion::pair serves the same purpose as the
//   _Tuple_elements in the above reference.
// 
#include <boost/fusion/support/pair.hpp>
#include <iostream>

using namespace boost;

  template
  < typename... TypePairs
  >
struct inherit_map
: TypePairs...
{

};

  template
  < typename Key
  , typename Value
  >
  Value const&
at_key( fusion::pair<Key,Value>const& a_pair)
{
    return a_pair.second;
}

template<int I>
struct ti
{
    int v;
    ti(int a=-1)
    : v(a)
    {}
};

  template
  < int I
  >
  std::ostream&
operator<<
( std::ostream& sout
, ti<I>const& x
)
{
    sout<<"ti<"<<I<<">("<<x.v<<")";
    return sout;
}
   
void test(void)
{
    std::cout<<"test:\n";
    
      inherit_map
      < fusion::pair<mpl::int_<1>,ti<1> >
      , fusion::pair<mpl::int_<2>,ti<2> >
      , fusion::pair<mpl::int_<3>,ti<3> >
      >
    map_valu
    ;   
    std::cout<<"at_key1="<<at_key<mpl::int_<1> >(map_valu)<<"\n";
    std::cout<<"at_key3="<<at_key<mpl::int_<3> >(map_valu)<<"\n";
}

int main(void)
{
    test();
    return 0;
}