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// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
9// ADDITIONAL_COMPILE_FLAGS(gcc-style-warnings): -Wno-ctad-maybe-unsupported
10
11// <mdspan>
12
13#include <array>
14#include <cassert>
15#include <cstddef>
16#include <cstdint>
17#include <mdspan>
18#include <span> // dynamic_extent
19#include <utility>
20
21#include "test_macros.h"
22
23// mdspan
24
25// layout_stride::mapping does not have explicit deduction guides,
26// but implicit deduction guides for constructor taking extents and strides
27// should work
28
29constexpr bool test() {
30 constexpr size_t D = std::dynamic_extent;
31
32 ASSERT_SAME_TYPE(decltype(std::layout_stride::mapping(std::extents<int>(), std::array<unsigned, 0>())),
33 std::layout_stride::mapping<std::extents<int>>);
34 ASSERT_SAME_TYPE(decltype(std::layout_stride::mapping(std::extents<int, 4>(), std::array<char, 1>{1})),
35 std::layout_stride::mapping<std::extents<int, 4>>);
36 ASSERT_SAME_TYPE(decltype(std::layout_stride::mapping(std::extents<int, D>(), std::array<char, 1>{1})),
37 std::layout_stride::mapping<std::extents<int, D>>);
38 ASSERT_SAME_TYPE(
39 decltype(std::layout_stride::mapping(std::extents<unsigned, D, 3>(), std::array<std::int64_t, 2>{3, 100})),
40 std::layout_stride::mapping<std::extents<unsigned, D, 3>>);
41
42 ASSERT_SAME_TYPE(decltype(std::layout_stride::mapping(std::extents<int>(), std::span<unsigned, 0>())),
43 std::layout_stride::mapping<std::extents<int>>);
44 ASSERT_SAME_TYPE(decltype(std::layout_stride::mapping(std::extents<int, 4>(), std::declval<std::span<char, 1>>())),
45 std::layout_stride::mapping<std::extents<int, 4>>);
46 ASSERT_SAME_TYPE(decltype(std::layout_stride::mapping(std::extents<int, D>(), std::declval<std::span<char, 1>>())),
47 std::layout_stride::mapping<std::extents<int, D>>);
48 ASSERT_SAME_TYPE(
49 decltype(std::layout_stride::mapping(std::extents<unsigned, D, 3>(), std::declval<std::span<std::int64_t, 2>>())),
50 std::layout_stride::mapping<std::extents<unsigned, D, 3>>);
51 return true;
52}
53
54int main(int, char**) {
55 test();
56 static_assert(test());
57 return 0;
58}
59

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