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//===----------------------------------------------------------------------===//
//
// 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
// constexpr const iterator_t<Base>& base() const & noexcept;
// constexpr iterator_t<Base> base() &&;
#include <cassert>
#include <ranges>
#include <tuple>
#include <type_traits>
#include <utility>
#include "MoveOnly.h"
#include "../types.h"
// Test Noexcept
template <class T>
concept IsBaseNoexcept =
requires {
{ std::declval<T>().base() } noexcept;
};
using BaseView = std::ranges::subrange<std::tuple<int>*>;
using ElementsIter = std::ranges::iterator_t<std::ranges::elements_view<BaseView, 0>>;
static_assert(IsBaseNoexcept<const ElementsIter&>);
static_assert(IsBaseNoexcept<ElementsIter&>);
static_assert(IsBaseNoexcept<const ElementsIter&&>);
LIBCPP_STATIC_ASSERT(!IsBaseNoexcept<ElementsIter&&>);
constexpr bool test() {
std::tuple<int> t{5};
// const &
{
const ElementsIter it{&t};
decltype(auto) base = it.base();
static_assert(std::is_same_v<decltype(base), std::tuple<int>* const&>);
assert(base == &t);
}
// &
{
ElementsIter it{&t};
decltype(auto) base = it.base();
static_assert(std::is_same_v<decltype(base), std::tuple<int>* const&>);
assert(base == &t);
}
// &&
{
ElementsIter it{&t};
decltype(auto) base = std::move(it).base();
static_assert(std::is_same_v<decltype(base), std::tuple<int>*>);
assert(base == &t);
}
// const &&
{
const ElementsIter it{&t};
decltype(auto) base = std::move(it).base();
static_assert(std::is_same_v<decltype(base), std::tuple<int>* const&>);
assert(base == &t);
}
// move only
{
struct MoveOnlyIter : IterBase<MoveOnlyIter> {
MoveOnly mo;
};
struct Sent {
constexpr bool operator==(const MoveOnlyIter&) const { return true; }
};
using MoveOnlyElemIter =
std::ranges::iterator_t<std::ranges::elements_view<std::ranges::subrange<MoveOnlyIter, Sent>, 0>>;
MoveOnlyElemIter it{MoveOnlyIter{{}, MoveOnly{5}}};
decltype(auto) base = std::move(it).base();
static_assert(std::is_same_v<decltype(base), MoveOnlyIter>);
assert(base.mo.get() == 5);
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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