# ifdef BOOST_OLD_CONCEPT_SUPPORT
# include <boost/concept_check/has_constraints.hpp>
-# include <boost/mpl/if.hpp>
+# include <boost/type_traits/conditional.hpp>
# endif
template <class Model>
struct concept_check
- : mpl::if_c<
+ : conditional<
concept_checking::has_constraints<Model>::value
, concept_checking::constraint_check<Model>
, concept_checking::concept_check_<Model>