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
9
10// <span>
11
12// template <class It>
13// constexpr explicit(Extent != dynamic_extent) span(It first, size_type count);
14// If Extent is not equal to dynamic_extent, then count shall be equal to Extent.
15//
16
17#include <cassert>
18#include <cstddef>
19#include <iterator>
20#include <span>
21#include <type_traits>
22
23template <std::size_t Extent>
24constexpr void test_constructibility() {
25 struct Other {};
26 static_assert(std::is_constructible_v<std::span<int, Extent>, int*, std::size_t>);
27 static_assert(!std::is_constructible_v<std::span<int, Extent>, const int*, std::size_t>);
28 static_assert(std::is_constructible_v<std::span<const int, Extent>, int*, std::size_t>);
29 static_assert(std::is_constructible_v<std::span<const int, Extent>, const int*, std::size_t>);
30 static_assert(!std::is_constructible_v<std::span<int, Extent>, volatile int*, std::size_t>);
31 static_assert(!std::is_constructible_v<std::span<int, Extent>, const volatile int*, std::size_t>);
32 static_assert(!std::is_constructible_v<std::span<const int, Extent>, volatile int*, std::size_t>);
33 static_assert(!std::is_constructible_v<std::span<const int, Extent>, const volatile int*, std::size_t>);
34 static_assert(!std::is_constructible_v<std::span<volatile int, Extent>, const int*, std::size_t>);
35 static_assert(!std::is_constructible_v<std::span<volatile int, Extent>, const volatile int*, std::size_t>);
36 static_assert(
37 !std::is_constructible_v<std::span<int, Extent>, double*, std::size_t>); // iterator type differs from span type
38 static_assert(!std::is_constructible_v<std::span<int, Extent>, std::size_t, size_t>);
39 static_assert(!std::is_constructible_v<std::span<int, Extent>, Other*, std::size_t>); // unrelated iterator type
40}
41
42template <class T>
43constexpr bool test_ctor() {
44 T val[2] = {};
45 auto s1 = std::span<T>(val, 2);
46 auto s2 = std::span<T, 2>(val, 2);
47 assert(s1.data() == std::data(val) && s1.size() == std::size(val));
48 assert(s2.data() == std::data(val) && s2.size() == std::size(val));
49 return true;
50}
51
52constexpr bool test() {
53 test_constructibility<std::dynamic_extent>();
54 test_constructibility<3>();
55
56 struct A {};
57 test_ctor<int>();
58 test_ctor<A>();
59
60 return true;
61}
62
63int main(int, char**) {
64 test();
65 static_assert(test());
66
67 return 0;
68}
69

source code of libcxx/test/std/containers/views/views.span/span.cons/iterator_len.pass.cpp