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/duplicate.hpp> 6 #include <boost/hana/extract.hpp> 7 #include <boost/hana/lazy.hpp> 8 namespace hana = boost::hana; 9 10 main()11int main() { 12 constexpr auto very_lazy = hana::duplicate(hana::make_lazy(3)); 13 static_assert(hana::extract(hana::extract(very_lazy)) == 3, ""); 14 } 15