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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
// owning_view() requires default_initializable<R> = default;
// constexpr owning_view(R&& t);
#include <ranges>
#include <cassert>
#include <concepts>
#include <type_traits>
#include <utility>
#include "test_macros.h"
struct DefaultConstructible {
int i;
constexpr explicit DefaultConstructible(int j = 42) : i(j) {}
int *begin() const;
int *end() const;
};
struct NotDefaultConstructible {
int i;
constexpr explicit NotDefaultConstructible(int j) : i(j) {}
int *begin() const;
int *end() const;
};
struct MoveChecker {
int i;
constexpr explicit MoveChecker(int j) : i(j) {}
constexpr MoveChecker(MoveChecker&& v) : i(std::exchange(v.i, -1)) {}
MoveChecker& operator=(MoveChecker&&);
int *begin() const;
int *end() const;
};
struct NoexceptChecker {
int *begin() const;
int *end() const;
};
constexpr bool test()
{
{
using OwningView = std::ranges::owning_view<DefaultConstructible>;
static_assert(std::is_constructible_v<OwningView>);
static_assert(std::default_initializable<OwningView>);
static_assert(std::movable<OwningView>);
static_assert(std::is_trivially_move_constructible_v<OwningView>);
static_assert(std::is_trivially_move_assignable_v<OwningView>);
static_assert(!std::is_copy_constructible_v<OwningView>);
static_assert(!std::is_copy_assignable_v<OwningView>);
static_assert(!std::is_constructible_v<OwningView, int>);
static_assert(!std::is_constructible_v<OwningView, DefaultConstructible&>);
static_assert(std::is_constructible_v<OwningView, DefaultConstructible&&>);
static_assert(!std::is_convertible_v<int, OwningView>);
static_assert(std::is_convertible_v<DefaultConstructible&&, OwningView>);
{
OwningView ov;
assert(ov.base().i == 42);
}
{
OwningView ov = OwningView(DefaultConstructible(1));
assert(ov.base().i == 1);
}
}
{
using OwningView = std::ranges::owning_view<NotDefaultConstructible>;
static_assert(!std::is_constructible_v<OwningView>);
static_assert(!std::default_initializable<OwningView>);
static_assert(std::movable<OwningView>);
static_assert(std::is_trivially_move_constructible_v<OwningView>);
static_assert(std::is_trivially_move_assignable_v<OwningView>);
static_assert(!std::is_copy_constructible_v<OwningView>);
static_assert(!std::is_copy_assignable_v<OwningView>);
static_assert(!std::is_constructible_v<OwningView, int>);
static_assert(!std::is_constructible_v<OwningView, NotDefaultConstructible&>);
static_assert(std::is_constructible_v<OwningView, NotDefaultConstructible&&>);
static_assert(!std::is_convertible_v<int, OwningView>);
static_assert(std::is_convertible_v<NotDefaultConstructible&&, OwningView>);
{
OwningView ov = OwningView(NotDefaultConstructible(1));
assert(ov.base().i == 1);
}
}
{
using OwningView = std::ranges::owning_view<MoveChecker>;
static_assert(!std::is_constructible_v<OwningView>);
static_assert(!std::default_initializable<OwningView>);
static_assert(std::movable<OwningView>);
static_assert(!std::is_trivially_move_constructible_v<OwningView>);
static_assert(!std::is_trivially_move_assignable_v<OwningView>);
static_assert(!std::is_copy_constructible_v<OwningView>);
static_assert(!std::is_copy_assignable_v<OwningView>);
static_assert(!std::is_constructible_v<OwningView, int>);
static_assert(!std::is_constructible_v<OwningView, MoveChecker&>);
static_assert(std::is_constructible_v<OwningView, MoveChecker&&>);
static_assert(!std::is_convertible_v<int, OwningView>);
static_assert(std::is_convertible_v<MoveChecker&&, OwningView>);
{
// Check that the constructor does indeed move from the target object.
auto m = MoveChecker(42);
OwningView ov = OwningView(std::move(m));
assert(ov.base().i == 42);
assert(m.i == -1);
}
}
{
// Check that the defaulted constructors are (not) noexcept when appropriate.
static_assert( std::is_nothrow_constructible_v<NoexceptChecker>); // therefore,
static_assert( std::is_nothrow_constructible_v<std::ranges::owning_view<NoexceptChecker>>);
static_assert(!std::is_nothrow_constructible_v<DefaultConstructible>); // therefore,
static_assert(!std::is_nothrow_constructible_v<std::ranges::owning_view<DefaultConstructible>>);
static_assert( std::is_nothrow_move_constructible_v<NoexceptChecker>); // therefore,
static_assert( std::is_nothrow_move_constructible_v<std::ranges::owning_view<NoexceptChecker>>);
static_assert(!std::is_nothrow_move_constructible_v<MoveChecker>); // therefore,
static_assert(!std::is_nothrow_move_constructible_v<std::ranges::owning_view<MoveChecker>>);
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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