ceph/src/boost/libs/hana/example/ext/std/tuple.cpp

   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
  20 int 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 }