//ChangeLog:
//  2011-01-07.1919CST
//    copied from attachment to:
//      http://article.gmane.org/gmane.comp.lib.boost.user/64988
//  2011-01-07.22309CST
//    Added one_of_maybe code and macro to switch beteen
//    that and boost::variant implementations.
//
#define VARIANT_TEST_SIZE 10
#define USE_SHARED_PTR 1
#define USE_ONE_OF_MAYBE 0

#if USE_ONE_OF_MAYBE
#else
  #include <boost/mpl/vector.hpp>
  #include <boost/variant/variant.hpp>
  #include <boost/variant/apply_visitor.hpp>
  #include <boost/variant/static_visitor.hpp>
#endif

#if USE_SHARED_PTR
  #include <boost/shared_ptr.hpp>
#endif

#include <boost/preprocessor/iteration/local.hpp>
#include <boost/preprocessor/cat.hpp>
#include <boost/preprocessor/enum.hpp>


#define BOOST_PP_LOCAL_MACRO(n) class BOOST_PP_CAT(C, n) { public: int i; };
#define BOOST_PP_LOCAL_LIMITS (0, VARIANT_TEST_SIZE)
#include BOOST_PP_LOCAL_ITERATE()

#if USE_SHARED_PTR
  #define VARIANT_ARG(z, n, data) boost::shared_ptr<BOOST_PP_CAT(C, n)> /**/
#else
  #define VARIANT_ARG(z, n, data) BOOST_PP_CAT(C, n) /**/
#endif
  
#if USE_ONE_OF_MAYBE
  #include <boost/composite_storage/pack/container_one_of_maybe.hpp>
      typedef 
    boost::composite_storage::pack::container
    < boost::composite_storage::tags::one_of_maybe
    , boost::mpl::integral_c<unsigned,0>
    , BOOST_PP_ENUM(VARIANT_TEST_SIZE, VARIANT_ARG, ~)
    >
  v_t;
#else
  typedef boost::mpl::vector<BOOST_PP_ENUM(VARIANT_TEST_SIZE, VARIANT_ARG, ~)> Mplv_t;
  typedef boost::make_variant_over<Mplv_t>::type v_t;
#endif  

void foo(const v_t& v)
{
//C: Copy variant using assignment operator
  v_t v2;
  v2 = v;
} 

int main()
{
  v_t v;
  foo(v);
  return 0;
}