1 // Copyright Louis Dionne 2013-2017 2 // Distributed under the Boost Software License, Version 1.0. 3 // (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt) 4 5 #include <boost/hana/assert.hpp> 6 #include <boost/hana/not.hpp> 7 #include <boost/hana/optional.hpp> 8 namespace hana = boost::hana; 9 10 11 BOOST_HANA_CONSTANT_CHECK( hana::is_nothing(hana::nothing)); 12 BOOST_HANA_CONSTANT_CHECK(!hana::is_nothing(hana::just('x'))); 13 BOOST_HANA_CONSTANT_CHECK(!hana::is_nothing(hana::just(hana::nothing))); 14 main()15int main() { } 16