Thank you so much Andrey! Just in case someone found this thread in the mailing list, this is a working example of the solution proposed in previous emails passing 3 types to evaluate: using test_types=boost::mpl::list<boost::mpl::vector<int, double, boost::mpl::quote2<std::pair>>,boost::mpl::vector<double, double, boost::mpl::quote2<std::pair>>>; BOOST_AUTO_TEST_CASE_TEMPLATE( types_match_test, T, test_types ){ //geting the types using A=typename boost::mpl::at<T, boost::mpl::int_<0>>::type; using B=typename boost::mpl::at<T, boost::mpl::int_<1>>::type; using C=typename boost::mpl::at<T, boost::mpl::int_<2>>::type; //creating the variables A a=0.5; B b=0.5; using CAB = typename C::template apply<A,B>::type; CAB c(a, b); BOOST_CHECK_EQUAL( a, b); BOOST_CHECK_EQUAL( c.first, c.second); } This fails 2 times and passes 2 times.