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 <experimental/string_view>
22 #include <cassert>
23 #include <type_traits>
24 
25 using std::experimental::string_view;
26 
27 template <class T>
28 void
test()29 test()
30 {
31     typedef std::hash<T> H;
32     static_assert((std::is_same<typename H::argument_type, T>::value), "" );
33     static_assert((std::is_same<typename H::result_type, std::size_t>::value), "" );
34     H h;
35 //     std::string g1 = "1234567890";
36 //     std::string g2 = "1234567891";
37     typedef typename T::value_type char_type;
38     char_type g1 [ 10 ];
39     char_type g2 [ 10 ];
40     for ( int i = 0; i < 10; ++i )
41         g1[i] = g2[9-i] = '0' + i;
42     T s1(g1, 10);
43     T s2(g2, 10);
44     assert(h(s1) != h(s2));
45 }
46 
main()47 int main()
48 {
49     test<std::experimental::string_view>();
50 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
51     test<std::experimental::u16string_view>();
52     test<std::experimental::u32string_view>();
53 #endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
54     test<std::experimental::wstring_view>();
55 }
56