// Copyright Louis Dionne 2013-2016 // Distributed under the Boost Software License, Version 1.0. // (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt) #include #include #include #include #include #include #include #include #include #include #include namespace hana = boost::hana; namespace mpl = boost::mpl; auto types = mpl::vector{}; auto number_of_floats = hana::fold_left(types, hana::int_c<0>, [](auto count, auto t) { return hana::if_(hana::trait(t), count + hana::int_c<1>, count ); }); BOOST_HANA_CONSTANT_CHECK(number_of_floats == hana::int_c<3>); int main() { }