1 // -*- C++ -*-
2 //===------------------------------ span ---------------------------------===//
3 //
4 //                     The LLVM Compiler Infrastructure
5 //
6 // This file is dual licensed under the MIT and the University of Illinois Open
7 // Source Licenses. See LICENSE.TXT for details.
8 //
9 //===---------------------------------------------------------------------===//
10 // UNSUPPORTED: c++98, c++03, c++11, c++14, c++17
11 
12 // <span>
13 
14 // constexpr reference operator[](index_type idx) const;
15 // constexpr reference operator()(index_type idx) const;
16 //
17 
18 
19 #include <span>
20 #include <cassert>
21 #include <string>
22 
23 #include "test_macros.h"
24 
25 
26 template <typename Span>
testConstexprSpan(Span sp,ptrdiff_t idx)27 constexpr bool testConstexprSpan(Span sp, ptrdiff_t idx)
28 {
29     _LIBCPP_ASSERT(noexcept(sp[idx]), "");
30     _LIBCPP_ASSERT(noexcept(sp(idx)), "");
31 
32     typename Span::reference r1 = sp[idx];
33     typename Span::reference r2 = sp(idx);
34     typename Span::reference r3 = *(sp.data() + idx);
35     return r1 == r2 && r2 == r3;
36 }
37 
38 
39 template <typename Span>
testRuntimeSpan(Span sp,ptrdiff_t idx)40 void testRuntimeSpan(Span sp, ptrdiff_t idx)
41 {
42     _LIBCPP_ASSERT(noexcept(sp[idx]), "");
43     _LIBCPP_ASSERT(noexcept(sp(idx)), "");
44 
45     typename Span::reference r1 = sp[idx];
46     typename Span::reference r2 = sp(idx);
47     typename Span::reference r3 = *(sp.data() + idx);
48     assert(r1 == r2 && r2 == r3);
49 }
50 
51 struct A{};
52 constexpr int iArr1[] = { 0,  1,  2,  3,  4,  5,  6,  7,  8,  9};
53           int iArr2[] = {10, 11, 12, 13, 14, 15, 16, 17, 18, 19};
54 
main()55 int main ()
56 {
57     static_assert(testConstexprSpan(std::span<const int>(iArr1, 1), 0), "");
58 
59     static_assert(testConstexprSpan(std::span<const int>(iArr1, 2), 0), "");
60     static_assert(testConstexprSpan(std::span<const int>(iArr1, 2), 1), "");
61 
62     static_assert(testConstexprSpan(std::span<const int>(iArr1, 3), 0), "");
63     static_assert(testConstexprSpan(std::span<const int>(iArr1, 3), 1), "");
64     static_assert(testConstexprSpan(std::span<const int>(iArr1, 3), 2), "");
65 
66     static_assert(testConstexprSpan(std::span<const int>(iArr1, 4), 0), "");
67     static_assert(testConstexprSpan(std::span<const int>(iArr1, 4), 1), "");
68     static_assert(testConstexprSpan(std::span<const int>(iArr1, 4), 2), "");
69     static_assert(testConstexprSpan(std::span<const int>(iArr1, 4), 3), "");
70 
71 
72     static_assert(testConstexprSpan(std::span<const int, 1>(iArr1, 1), 0), "");
73 
74     static_assert(testConstexprSpan(std::span<const int, 2>(iArr1, 2), 0), "");
75     static_assert(testConstexprSpan(std::span<const int, 2>(iArr1, 2), 1), "");
76 
77     static_assert(testConstexprSpan(std::span<const int, 3>(iArr1, 3), 0), "");
78     static_assert(testConstexprSpan(std::span<const int, 3>(iArr1, 3), 1), "");
79     static_assert(testConstexprSpan(std::span<const int, 3>(iArr1, 3), 2), "");
80 
81     static_assert(testConstexprSpan(std::span<const int, 4>(iArr1, 4), 0), "");
82     static_assert(testConstexprSpan(std::span<const int, 4>(iArr1, 4), 1), "");
83     static_assert(testConstexprSpan(std::span<const int, 4>(iArr1, 4), 2), "");
84     static_assert(testConstexprSpan(std::span<const int, 4>(iArr1, 4), 3), "");
85 
86 
87     testRuntimeSpan(std::span<int>(iArr2, 1), 0);
88 
89     testRuntimeSpan(std::span<int>(iArr2, 2), 0);
90     testRuntimeSpan(std::span<int>(iArr2, 2), 1);
91 
92     testRuntimeSpan(std::span<int>(iArr2, 3), 0);
93     testRuntimeSpan(std::span<int>(iArr2, 3), 1);
94     testRuntimeSpan(std::span<int>(iArr2, 3), 2);
95 
96     testRuntimeSpan(std::span<int>(iArr2, 4), 0);
97     testRuntimeSpan(std::span<int>(iArr2, 4), 1);
98     testRuntimeSpan(std::span<int>(iArr2, 4), 2);
99     testRuntimeSpan(std::span<int>(iArr2, 4), 3);
100 
101 
102     testRuntimeSpan(std::span<int, 1>(iArr2, 1), 0);
103 
104     testRuntimeSpan(std::span<int, 2>(iArr2, 2), 0);
105     testRuntimeSpan(std::span<int, 2>(iArr2, 2), 1);
106 
107     testRuntimeSpan(std::span<int, 3>(iArr2, 3), 0);
108     testRuntimeSpan(std::span<int, 3>(iArr2, 3), 1);
109     testRuntimeSpan(std::span<int, 3>(iArr2, 3), 2);
110 
111     testRuntimeSpan(std::span<int, 4>(iArr2, 4), 0);
112     testRuntimeSpan(std::span<int, 4>(iArr2, 4), 1);
113     testRuntimeSpan(std::span<int, 4>(iArr2, 4), 2);
114     testRuntimeSpan(std::span<int, 4>(iArr2, 4), 3);
115 
116     std::string s;
117     testRuntimeSpan(std::span<std::string>   (&s, 1), 0);
118     testRuntimeSpan(std::span<std::string, 1>(&s, 1), 0);
119 }
120