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
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
|
// -*- C++ -*-
//===------------------------------ span ---------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===---------------------------------------------------------------------===//
// UNSUPPORTED: c++03, c++11, c++14, c++17
// <span>
// template<size_t Count>
// constexpr span<element_type, Count> last() const;
//
// constexpr span<element_type, dynamic_extent> last(size_type count) const;
//
// Requires: Count <= size().
#include <span>
#include <cassert>
#include <algorithm>
#include <string>
#include "test_macros.h"
template <typename Span, size_t Count>
constexpr bool testConstexprSpan(Span sp)
{
LIBCPP_ASSERT((noexcept(sp.template last<Count>())));
LIBCPP_ASSERT((noexcept(sp.last(Count))));
auto s1 = sp.template last<Count>();
auto s2 = sp.last(Count);
using S1 = decltype(s1);
using S2 = decltype(s2);
ASSERT_SAME_TYPE(typename Span::value_type, typename S1::value_type);
ASSERT_SAME_TYPE(typename Span::value_type, typename S2::value_type);
static_assert(S1::extent == Count, "");
static_assert(S2::extent == std::dynamic_extent, "");
return
s1.data() == s2.data()
&& s1.size() == s2.size()
&& std::equal(s1.begin(), s1.end(), sp.end() - Count);
}
template <typename Span, size_t Count>
void testRuntimeSpan(Span sp)
{
LIBCPP_ASSERT((noexcept(sp.template last<Count>())));
LIBCPP_ASSERT((noexcept(sp.last(Count))));
auto s1 = sp.template last<Count>();
auto s2 = sp.last(Count);
using S1 = decltype(s1);
using S2 = decltype(s2);
ASSERT_SAME_TYPE(typename Span::value_type, typename S1::value_type);
ASSERT_SAME_TYPE(typename Span::value_type, typename S2::value_type);
static_assert(S1::extent == Count, "");
static_assert(S2::extent == std::dynamic_extent, "");
assert(s1.data() == s2.data());
assert(s1.size() == s2.size());
assert(std::equal(s1.begin(), s1.end(), sp.end() - Count));
}
constexpr int carr1[] = {1,2,3,4};
int arr[] = {5,6,7};
std::string sarr [] = { "ABC", "DEF", "GHI", "JKL", "MNO"};
int main(int, char**)
{
{
using Sp = std::span<const int>;
static_assert(testConstexprSpan<Sp, 0>(Sp{}), "");
static_assert(testConstexprSpan<Sp, 0>(Sp{carr1}), "");
static_assert(testConstexprSpan<Sp, 1>(Sp{carr1}), "");
static_assert(testConstexprSpan<Sp, 2>(Sp{carr1}), "");
static_assert(testConstexprSpan<Sp, 3>(Sp{carr1}), "");
static_assert(testConstexprSpan<Sp, 4>(Sp{carr1}), "");
}
{
using Sp = std::span<const int, 4>;
static_assert(testConstexprSpan<Sp, 0>(Sp{carr1}), "");
static_assert(testConstexprSpan<Sp, 1>(Sp{carr1}), "");
static_assert(testConstexprSpan<Sp, 2>(Sp{carr1}), "");
static_assert(testConstexprSpan<Sp, 3>(Sp{carr1}), "");
static_assert(testConstexprSpan<Sp, 4>(Sp{carr1}), "");
}
{
using Sp = std::span<int>;
testRuntimeSpan<Sp, 0>(Sp{});
testRuntimeSpan<Sp, 0>(Sp{arr});
testRuntimeSpan<Sp, 1>(Sp{arr});
testRuntimeSpan<Sp, 2>(Sp{arr});
testRuntimeSpan<Sp, 3>(Sp{arr});
}
{
using Sp = std::span<int, 3>;
testRuntimeSpan<Sp, 0>(Sp{arr});
testRuntimeSpan<Sp, 1>(Sp{arr});
testRuntimeSpan<Sp, 2>(Sp{arr});
testRuntimeSpan<Sp, 3>(Sp{arr});
}
{
using Sp = std::span<std::string>;
testConstexprSpan<Sp, 0>(Sp{});
testRuntimeSpan<Sp, 0>(Sp{sarr});
testRuntimeSpan<Sp, 1>(Sp{sarr});
testRuntimeSpan<Sp, 2>(Sp{sarr});
testRuntimeSpan<Sp, 3>(Sp{sarr});
testRuntimeSpan<Sp, 4>(Sp{sarr});
testRuntimeSpan<Sp, 5>(Sp{sarr});
}
{
using Sp = std::span<std::string, 5>;
testRuntimeSpan<Sp, 0>(Sp{sarr});
testRuntimeSpan<Sp, 1>(Sp{sarr});
testRuntimeSpan<Sp, 2>(Sp{sarr});
testRuntimeSpan<Sp, 3>(Sp{sarr});
testRuntimeSpan<Sp, 4>(Sp{sarr});
testRuntimeSpan<Sp, 5>(Sp{sarr});
}
return 0;
}
|
