112 lines · cpp
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-exception6//7//===----------------------------------------------------------------------===//8// UNSUPPORTED: c++03, c++11, c++14, c++179 10// <span>11 12// template<size_t N>13// constexpr span(array<value_type, N>& arr) noexcept;14// template<size_t N>15// constexpr span(const array<value_type, N>& arr) noexcept;16//17// Remarks: These constructors shall not participate in overload resolution unless:18// - extent == dynamic_extent || N == extent is true, and19// - remove_pointer_t<decltype(data(arr))>(*)[] is convertible to ElementType(*)[].20//21 22#include <span>23#include <array>24#include <cassert>25#include <string>26 27#include "test_macros.h"28 29void checkCV() {30 std::array<int, 3> arr = {1, 2, 3};31 // STL says these are not cromulent32 // std::array<const int,3> carr = {4,5,6};33 // std::array<volatile int, 3> varr = {7,8,9};34 // std::array<const volatile int, 3> cvarr = {1,3,5};35 36 // Types the same (dynamic sized)37 {38 std::span< int> s1{arr}; // a span< int> pointing at int.39 }40 41 // Types the same (static sized)42 {43 std::span< int, 3> s1{arr}; // a span< int> pointing at int.44 }45 46 // types different (dynamic sized)47 {48 std::span<const int> s1{arr}; // a span<const int> pointing at int.49 std::span< volatile int> s2{arr}; // a span< volatile int> pointing at int.50 std::span< volatile int> s3{arr}; // a span< volatile int> pointing at const int.51 std::span<const volatile int> s4{arr}; // a span<const volatile int> pointing at int.52 }53 54 // types different (static sized)55 {56 std::span<const int, 3> s1{arr}; // a span<const int> pointing at int.57 std::span< volatile int, 3> s2{arr}; // a span< volatile int> pointing at int.58 std::span< volatile int, 3> s3{arr}; // a span< volatile int> pointing at const int.59 std::span<const volatile int, 3> s4{arr}; // a span<const volatile int> pointing at int.60 }61}62 63template <typename T, typename U>64constexpr bool testConstructorArray() {65 std::array<U, 2> val = {U(), U()};66 ASSERT_NOEXCEPT(std::span<T>{val});67 ASSERT_NOEXCEPT(std::span<T, 2>{val});68 std::span<T> s1{val};69 std::span<T, 2> s2{val};70 return s1.data() == &val[0] && s1.size() == 2 && s2.data() == &val[0] && s2.size() == 2;71}72 73template <typename T, typename U>74constexpr bool testConstructorConstArray() {75 const std::array<U, 2> val = {U(), U()};76 ASSERT_NOEXCEPT(std::span<const T>{val});77 ASSERT_NOEXCEPT(std::span<const T, 2>{val});78 std::span<const T> s1{val};79 std::span<const T, 2> s2{val};80 return s1.data() == &val[0] && s1.size() == 2 && s2.data() == &val[0] && s2.size() == 2;81}82 83template <typename T>84constexpr bool testConstructors() {85 static_assert(testConstructorArray<T, T>(), "");86 static_assert(testConstructorArray<const T, const T>(), "");87 static_assert(testConstructorArray<const T, T>(), "");88 static_assert(testConstructorConstArray<T, T>(), "");89 static_assert(testConstructorConstArray<const T, const T>(), "");90 static_assert(testConstructorConstArray<const T, T>(), "");91 92 return testConstructorArray<T, T>() && testConstructorArray<const T, const T>() &&93 testConstructorArray<const T, T>() && testConstructorConstArray<T, T>() &&94 testConstructorConstArray<const T, const T>() && testConstructorConstArray<const T, T>();95}96 97struct A {};98 99int main(int, char**) {100 assert(testConstructors<int>());101 assert(testConstructors<long>());102 assert(testConstructors<double>());103 assert(testConstructors<A>());104 105 assert(testConstructors<int*>());106 assert(testConstructors<const int*>());107 108 checkCV();109 110 return 0;111}112