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/tuple.hpp>
7 
8 #include <string>
9 namespace hana = boost::hana;
10 
11 
12 struct Empty { };
13 
main()14 int main() {
15     {
16         using T = hana::tuple<int>;
17         const T t(3);
18         BOOST_HANA_RUNTIME_CHECK(hana::at_c<0>(t) == 3);
19     }
20     {
21         using T = hana::tuple<std::string, int>;
22         const T t("high", 5);
23         BOOST_HANA_RUNTIME_CHECK(hana::at_c<0>(t) == "high");
24         BOOST_HANA_RUNTIME_CHECK(hana::at_c<1>(t) == 5);
25     }
26     {
27         using T = hana::tuple<double, int>;
28         constexpr T t(2.718, 5);
29         static_assert(hana::at_c<0>(t) == 2.718, "");
30         static_assert(hana::at_c<1>(t) == 5, "");
31     }
32     {
33         using T = hana::tuple<Empty>;
34         constexpr T t{Empty()};
35         constexpr Empty e = hana::at_c<0>(t); (void)e;
36     }
37     {
38         using T = hana::tuple<double&, std::string, int>;
39         double d = 1.5;
40         const T t(d, "high", 5);
41         BOOST_HANA_RUNTIME_CHECK(hana::at_c<0>(t) == 1.5);
42         BOOST_HANA_RUNTIME_CHECK(hana::at_c<1>(t) == "high");
43         BOOST_HANA_RUNTIME_CHECK(hana::at_c<2>(t) == 5);
44         hana::at_c<0>(t) = 2.5;
45         BOOST_HANA_RUNTIME_CHECK(hana::at_c<0>(t) == 2.5);
46         BOOST_HANA_RUNTIME_CHECK(hana::at_c<1>(t) == "high");
47         BOOST_HANA_RUNTIME_CHECK(hana::at_c<2>(t) == 5);
48         BOOST_HANA_RUNTIME_CHECK(d == 2.5);
49     }
50 }
51