//===----------------------------------------------------------------------===//
//
// 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
// <optional>
// template <class U> constexpr T optional<T>::value_or(U&& v) &&;
#include <optional>
#include <type_traits>
#include <cassert>
#include "test_macros.h"
using std::optional;
using std::in_place_t;
using std::in_place;
struct Y
{
int i_;
constexpr Y(int i) : i_(i) {}
};
struct X
{
int i_;
constexpr X(int i) : i_(i) {}
constexpr X(X&& x) : i_(x.i_) {x.i_ = 0;}
constexpr X(const Y& y) : i_(y.i_) {}
constexpr X(Y&& y) : i_(y.i_+1) {}
friend constexpr bool operator==(const X& x, const X& y)
{return x.i_ == y.i_;}
};
constexpr int test()
{
{
optional<X> opt(in_place, 2);
Y y(3);
assert(std::move(opt).value_or(y) == 2);
assert(*opt == 0);
}
{
optional<X> opt(in_place, 2);
assert(std::move(opt).value_or(Y(3)) == 2);
assert(*opt == 0);
}
{
optional<X> opt;
Y y(3);
assert(std::move(opt).value_or(y) == 3);
assert(!opt);
}
{
optional<X> opt;
assert(std::move(opt).value_or(Y(3)) == 4);
assert(!opt);
}
return 0;
}
int main(int, char**)
{
static_assert(test() == 0);
return 0;
}