1 //
2 // cpp14/prefer_static.cpp
3 // ~~~~~~~~~~~~~~~~~~~~~~~
4 //
5 // Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
6 //
7 // Distributed under the Boost Software License, Version 1.0. (See accompanying
8 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
9 //
10
11 #include <boost/asio/prefer.hpp>
12 #include <cassert>
13
14 template <int>
15 struct prop
16 {
17 template <typename> static constexpr bool is_applicable_property_v = true;
18 static constexpr bool is_preferable = true;
19 template <typename> static constexpr bool static_query_v = true;
valueprop20 static constexpr bool value() { return true; }
21 };
22
23 template <int>
24 struct object
25 {
26 };
27
main()28 int main()
29 {
30 object<1> o1 = {};
31 object<1> o2 = boost::asio::prefer(o1, prop<1>());
32 object<1> o3 = boost::asio::prefer(o1, prop<1>(), prop<1>());
33 object<1> o4 = boost::asio::prefer(o1, prop<1>(), prop<1>(), prop<1>());
34 (void)o2;
35 (void)o3;
36 (void)o4;
37
38 const object<1> o5 = {};
39 object<1> o6 = boost::asio::prefer(o5, prop<1>());
40 object<1> o7 = boost::asio::prefer(o5, prop<1>(), prop<1>());
41 object<1> o8 = boost::asio::prefer(o5, prop<1>(), prop<1>(), prop<1>());
42 (void)o6;
43 (void)o7;
44 (void)o8;
45
46 constexpr object<1> o9 = boost::asio::prefer(object<1>(), prop<1>());
47 constexpr object<1> o10 = boost::asio::prefer(object<1>(), prop<1>(), prop<1>());
48 constexpr object<1> o11 = boost::asio::prefer(object<1>(), prop<1>(), prop<1>(), prop<1>());
49 (void)o9;
50 (void)o10;
51 (void)o11;
52 }
53