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/equal.hpp> 7 #include <boost/hana/ext/std/tuple.hpp> 8 #include <boost/hana/integral_constant.hpp> 9 #include <boost/hana/transform.hpp> 10 11 #include <string> 12 #include <tuple> 13 namespace hana = boost::hana; 14 15 16 struct Fish { std::string name; }; 17 struct Cat { std::string name; }; 18 struct Dog { std::string name; }; 19 main()20int main() { 21 std::tuple<Fish, Cat, Dog> animals{{"Nemo"}, {"Garfield"}, {"Snoopy"}}; 22 hana::front(animals).name = "Moby Dick"; 23 24 auto names = hana::transform(animals, [](auto a) { 25 return a.name; 26 }); 27 28 BOOST_HANA_RUNTIME_CHECK(hana::equal( 29 names, 30 std::make_tuple("Moby Dick", "Garfield", "Snoopy") 31 )); 32 } 33