1
2 // Copyright 2017 Peter Dimov.
3 //
4 // Distributed under the Boost Software License, Version 1.0.
5 //
6 // See accompanying file LICENSE_1_0.txt or copy at
7 // http://www.boost.org/LICENSE_1_0.txt
8
9
10 #include <boost/mp11/utility.hpp>
11 #include <boost/core/lightweight_test_trait.hpp>
12 #include <type_traits>
13
14 using boost::mp11::mp_eval_if;
15 using boost::mp11::mp_eval_if_q;
16 using boost::mp11::mp_identity_t;
17 using boost::mp11::mp_valid;
18 using boost::mp11::mp_quote;
19
20 template<class C, class... A> using eval_if = mp_eval_if<C, void, mp_identity_t, A...>;
21
main()22 int main()
23 {
24 BOOST_TEST_TRAIT_TRUE((mp_valid<eval_if, std::true_type>));
25 BOOST_TEST_TRAIT_TRUE((mp_valid<eval_if, std::true_type, void>));
26 BOOST_TEST_TRAIT_TRUE((mp_valid<eval_if, std::true_type, void, void>));
27 BOOST_TEST_TRAIT_TRUE((mp_valid<eval_if, std::true_type, void, void, void>));
28
29 BOOST_TEST_TRAIT_FALSE((mp_valid<eval_if, std::false_type>));
30 BOOST_TEST_TRAIT_TRUE((mp_valid<eval_if, std::false_type, void>));
31 BOOST_TEST_TRAIT_FALSE((mp_valid<eval_if, std::false_type, void, void>));
32 BOOST_TEST_TRAIT_FALSE((mp_valid<eval_if, std::false_type, void, void, void>));
33
34 using Qi = mp_quote<mp_identity_t>;
35
36 BOOST_TEST_TRAIT_TRUE((mp_valid<mp_eval_if_q, std::true_type, void, Qi>));
37 BOOST_TEST_TRAIT_TRUE((mp_valid<mp_eval_if_q, std::true_type, void, Qi, void>));
38 BOOST_TEST_TRAIT_TRUE((mp_valid<mp_eval_if_q, std::true_type, void, Qi, void, void>));
39 BOOST_TEST_TRAIT_TRUE((mp_valid<mp_eval_if_q, std::true_type, void, Qi, void, void, void>));
40
41 BOOST_TEST_TRAIT_FALSE((mp_valid<mp_eval_if_q, std::false_type, void, Qi>));
42 BOOST_TEST_TRAIT_TRUE((mp_valid<mp_eval_if_q, std::false_type, void, Qi, void>));
43 BOOST_TEST_TRAIT_FALSE((mp_valid<mp_eval_if_q, std::false_type, void, Qi, void, void>));
44 BOOST_TEST_TRAIT_FALSE((mp_valid<mp_eval_if_q, std::false_type, void, Qi, void, void, void>));
45
46 return boost::report_errors();
47 }
48