1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
|
//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// <functional>
// template <class T>
// struct hash
// : public unary_function<T, size_t>
// {
// size_t operator()(T val) const;
// };
// Not very portable
#include <functional>
#include <cassert>
#include <type_traits>
#include <limits>
#include "test_macros.h"
template <class T>
void
test()
{
typedef std::hash<T> H;
static_assert((std::is_same<typename H::argument_type, T>::value), "" );
static_assert((std::is_same<typename H::result_type, std::size_t>::value), "" );
ASSERT_NOEXCEPT(H()(T()));
H h;
typedef typename std::remove_pointer<T>::type type;
type i;
type j;
assert(h(&i) != h(&j));
}
// can't hash nullptr_t until C++17
void test_nullptr()
{
#if TEST_STD_VER > 14
typedef std::nullptr_t T;
typedef std::hash<T> H;
static_assert((std::is_same<typename H::argument_type, T>::value), "" );
static_assert((std::is_same<typename H::result_type, std::size_t>::value), "" );
ASSERT_NOEXCEPT(H()(T()));
#endif
}
int main()
{
test<int*>();
test_nullptr();
}
|
