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()11 int main() {
12     constexpr auto very_lazy = hana::duplicate(hana::make_lazy(3));
13     static_assert(hana::extract(hana::extract(very_lazy)) == 3, "");
14 }
15