1 //===----------------------------------------------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 // <functional>
11 
12 // template <class T>
13 // struct hash
14 //     : public unary_function<T, size_t>
15 // {
16 //     size_t operator()(T val) const;
17 // };
18 
19 // Not very portable
20 
21 #include <functional>
22 #include <cassert>
23 #include <type_traits>
24 #include <limits>
25 
26 template <class T>
27 void
28 test()
29 {
30     static_assert((std::is_base_of<std::unary_function<T, std::size_t>,
31                                    std::hash<T> >::value), "");
32     std::hash<T> h;
33     for (int i = 0; i <= 5; ++i)
34     {
35         T t(i);
36         if (sizeof(T) <= sizeof(std::size_t))
37             assert(h(t) == t);
38     }
39 }
40 
41 int main()
42 {
43     test<bool>();
44     test<char>();
45     test<signed char>();
46     test<unsigned char>();
47     test<char16_t>();
48     test<char32_t>();
49     test<wchar_t>();
50     test<short>();
51     test<unsigned short>();
52     test<int>();
53     test<unsigned int>();
54     test<long>();
55     test<unsigned long>();
56     test<long long>();
57     test<unsigned long long>();
58 }
59