| // -*- C++ -*- |
| //===------------------------------ span ---------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===---------------------------------------------------------------------===// |
| // UNSUPPORTED: c++03, c++11, c++14, c++17 |
| |
| // <span> |
| |
| // template<size_t N> |
| // constexpr span(array<value_type, N>& arr) noexcept; |
| // template<size_t N> |
| // constexpr span(const array<value_type, N>& arr) noexcept; |
| // |
| // Remarks: These constructors shall not participate in overload resolution unless: |
| // — extent == dynamic_extent || N == extent is true, and |
| // — remove_pointer_t<decltype(data(arr))>(*)[] is convertible to ElementType(*)[]. |
| // |
| |
| |
| #include <span> |
| #include <array> |
| #include <cassert> |
| #include <string> |
| |
| #include "test_macros.h" |
| // std::array is explicitly allowed to be initialized with A a = { init-list };. |
| // Disable the missing braces warning for this reason. |
| #include "disable_missing_braces_warning.h" |
| |
| |
| void checkCV() |
| { |
| std::array<int, 3> arr = {1,2,3}; |
| // STL says these are not cromulent |
| // std::array<const int,3> carr = {4,5,6}; |
| // std::array<volatile int, 3> varr = {7,8,9}; |
| // std::array<const volatile int, 3> cvarr = {1,3,5}; |
| |
| // Types the same (dynamic sized) |
| { |
| std::span< int> s1{ arr}; // a span< int> pointing at int. |
| } |
| |
| // Types the same (static sized) |
| { |
| std::span< int,3> s1{ arr}; // a span< int> pointing at int. |
| } |
| |
| |
| // types different (dynamic sized) |
| { |
| std::span<const int> s1{ arr}; // a span<const int> pointing at int. |
| std::span< volatile int> s2{ arr}; // a span< volatile int> pointing at int. |
| std::span< volatile int> s3{ arr}; // a span< volatile int> pointing at const int. |
| std::span<const volatile int> s4{ arr}; // a span<const volatile int> pointing at int. |
| } |
| |
| // types different (static sized) |
| { |
| std::span<const int,3> s1{ arr}; // a span<const int> pointing at int. |
| std::span< volatile int,3> s2{ arr}; // a span< volatile int> pointing at int. |
| std::span< volatile int,3> s3{ arr}; // a span< volatile int> pointing at const int. |
| std::span<const volatile int,3> s4{ arr}; // a span<const volatile int> pointing at int. |
| } |
| } |
| |
| template <typename T, typename U> |
| constexpr bool testConstructorArray() { |
| std::array<U, 2> val = {U(), U()}; |
| ASSERT_NOEXCEPT(std::span<T>{val}); |
| ASSERT_NOEXCEPT(std::span<T, 2>{val}); |
| std::span<T> s1{val}; |
| std::span<T, 2> s2{val}; |
| return s1.data() == &val[0] && s1.size() == 2 && s2.data() == &val[0] && |
| s2.size() == 2; |
| } |
| |
| template <typename T, typename U> |
| constexpr bool testConstructorConstArray() { |
| const std::array<U, 2> val = {U(), U()}; |
| ASSERT_NOEXCEPT(std::span<const T>{val}); |
| ASSERT_NOEXCEPT(std::span<const T, 2>{val}); |
| std::span<const T> s1{val}; |
| std::span<const T, 2> s2{val}; |
| return s1.data() == &val[0] && s1.size() == 2 && s2.data() == &val[0] && |
| s2.size() == 2; |
| } |
| |
| template <typename T> |
| constexpr bool testConstructors() { |
| static_assert(testConstructorArray<T, T>(), ""); |
| static_assert(testConstructorArray<const T, const T>(), ""); |
| static_assert(testConstructorArray<const T, T>(), ""); |
| static_assert(testConstructorConstArray<T, T>(), ""); |
| static_assert(testConstructorConstArray<const T, const T>(), ""); |
| static_assert(testConstructorConstArray<const T, T>(), ""); |
| |
| return testConstructorArray<T, T>() && |
| testConstructorArray<const T, const T>() && |
| testConstructorArray<const T, T>() && |
| testConstructorConstArray<T, T>() && |
| testConstructorConstArray<const T, const T>() && |
| testConstructorConstArray<const T, T>(); |
| } |
| |
| struct A{}; |
| |
| int main(int, char**) |
| { |
| assert(testConstructors<int>()); |
| assert(testConstructors<long>()); |
| assert(testConstructors<double>()); |
| assert(testConstructors<A>()); |
| |
| assert(testConstructors<int*>()); |
| assert(testConstructors<const int*>()); |
| |
| checkCV(); |
| |
| return 0; |
| } |