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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
// UNSUPPORTED: libcpp-has-no-incomplete-ranges
// std::views::single
#include <ranges>
#include <cassert>
#include <concepts>
#include <utility>
#include "MoveOnly.h"
// Can't invoke without arguments.
static_assert(!std::is_invocable_v<decltype((std::views::single))>);
// Can't invoke with a move-only type.
static_assert(!std::is_invocable_v<decltype((std::views::single)), MoveOnly>);
constexpr bool test() {
// Lvalue.
{
int x = 42;
std::same_as<std::ranges::single_view<int>> decltype(auto) v = std::views::single(x);
assert(v.size() == 1);
assert(v.front() == x);
}
// Prvalue.
{
std::same_as<std::ranges::single_view<int>> decltype(auto) v = std::views::single(42);
assert(v.size() == 1);
assert(v.front() == 42);
}
// Const lvalue.
{
const int x = 42;
std::same_as<std::ranges::single_view<int>> decltype(auto) v = std::views::single(x);
assert(v.size() == 1);
assert(v.front() == x);
}
// Xvalue.
{
int x = 42;
std::same_as<std::ranges::single_view<int>> decltype(auto) v = std::views::single(std::move(x));
assert(v.size() == 1);
assert(v.front() == x);
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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