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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 void emplace() noexcept;
//
// Effects: If has_value() is false, destroys unex and sets has_val to true.
#include <cassert>
#include <concepts>
#include <expected>
#include <type_traits>
#include <utility>
#include "../../types.h"
#include "test_macros.h"
template <class T>
concept EmplaceNoexcept =
requires(T t) {
{ t.emplace() } noexcept;
};
static_assert(!EmplaceNoexcept<int>);
static_assert(EmplaceNoexcept<std::expected<void, int>>);
constexpr bool test() {
// has_value
{
std::expected<void, int> e;
e.emplace();
assert(e.has_value());
}
// !has_value
{
Traced::state state{};
std::expected<int, Traced> e(std::unexpect, state, 5);
e.emplace();
assert(state.dtorCalled);
assert(e.has_value());
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
return 0;
}
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