//===----------------------------------------------------------------------===//
//
// 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"
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;
}