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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, c++20
// constexpr explicit operator bool() const noexcept;
#include <cassert>
#include <concepts>
#include <expected>
#include <type_traits>
#include <utility>
#include "test_macros.h"
// Test noexcept
template <class T>
concept OpBoolNoexcept =
requires(T t) {
{ static_cast<bool>(t) } noexcept;
};
struct Foo {};
static_assert(!OpBoolNoexcept<Foo>);
static_assert(OpBoolNoexcept<std::expected<int, int>>);
static_assert(OpBoolNoexcept<const std::expected<int, int>>);
// Test explicit
static_assert(!std::is_convertible_v<std::expected<int, int>, bool>);
constexpr bool test() {
// has_value
{
const std::expected<int, int> e(5);
assert(static_cast<bool>(e));
}
// !has_value
{
const std::expected<int, int> e(std::unexpect, 5);
assert(!static_cast<bool>(e));
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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