1//===----------------------------------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
10
11// <mdspan>
12
13// constexpr index_type stride(rank_type i) const noexcept;
14//
15// Constraints: extents_type::rank() > 0 is true.
16//
17// Preconditions: i < extents_type::rank() is true.
18//
19// Returns: extents().rev-prod-of-extents(i).
20
21#include <mdspan>
22#include <cassert>
23#include <array>
24#include <cstdint>
25#include <cstdio>
26#include "test_macros.h"
27
28template <class E, class... Args>
29constexpr void test_stride(std::array<typename E::index_type, E::rank()> strides, Args... args) {
30 using M = std::layout_stride::mapping<E>;
31 M m(E(args...), strides);
32
33 ASSERT_NOEXCEPT(m.stride(0));
34 for (size_t r = 0; r < E::rank(); r++)
35 assert(strides[r] == m.stride(r));
36
37 ASSERT_NOEXCEPT(m.strides());
38 auto strides_out = m.strides();
39 static_assert(std::is_same_v<decltype(strides_out), std::array<typename E::index_type, E::rank()>>);
40 for (size_t r = 0; r < E::rank(); r++)
41 assert(strides[r] == strides_out[r]);
42}
43
44constexpr bool test() {
45 constexpr size_t D = std::dynamic_extent;
46 test_stride<std::extents<unsigned, D>>(std::array<unsigned, 1>{1}, 7);
47 test_stride<std::extents<unsigned, 7>>(std::array<unsigned, 1>{1});
48 test_stride<std::extents<unsigned, 7, 8>>(std::array<unsigned, 2>{8, 1});
49 test_stride<std::extents<int64_t, D, 8, D, D>>(std::array<int64_t, 4>{720, 90, 10, 1}, 7, 9, 10);
50 return true;
51}
52
53int main(int, char**) {
54 test();
55 static_assert(test());
56 return 0;
57}
58

source code of libcxx/test/std/containers/views/mdspan/layout_stride/stride.pass.cpp