1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 // <algorithm>
10 
11 // template<LessThanComparable T>
12 //   pair<const T&, const T&>
13 //   minmax(const T& a, const T& b);
14 
15 #include <algorithm>
16 #include <cassert>
17 
18 #include "test_macros.h"
19 
20 template <class T>
21 void
test(const T & a,const T & b,const T & x,const T & y)22 test(const T& a, const T& b, const T& x, const T& y)
23 {
24     std::pair<const T&, const T&> p = std::minmax(a, b);
25     assert(&p.first == &x);
26     assert(&p.second == &y);
27 }
28 
main(int,char **)29 int main(int, char**)
30 {
31     {
32     int x = 0;
33     int y = 0;
34     test(x, y, x, y);
35     test(y, x, y, x);
36     }
37     {
38     int x = 0;
39     int y = 1;
40     test(x, y, x, y);
41     test(y, x, x, y);
42     }
43     {
44     int x = 1;
45     int y = 0;
46     test(x, y, y, x);
47     test(y, x, y, x);
48     }
49 #if TEST_STD_VER >= 14
50     {
51 //  Note that you can't take a reference to a local var, since
52 //  its address is not a compile-time constant.
53     constexpr static int x = 1;
54     constexpr static int y = 0;
55     constexpr auto p1 = std::minmax (x, y);
56     static_assert(p1.first  == y, "");
57     static_assert(p1.second == x, "");
58     constexpr auto p2 = std::minmax (y, x);
59     static_assert(p2.first  == y, "");
60     static_assert(p2.second == x, "");
61     }
62 #endif
63 
64   return 0;
65 }
66