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//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++98, c++03, c++11, c++14
// <optional>
// template <class T, class... Args>
// constexpr optional<T> make_optional(Args&&... args);
#include <optional>
#include <string>
#include <memory>
#include <cassert>
int main()
{
using std::optional;
using std::make_optional;
{
constexpr auto opt = make_optional<int>('a');
static_assert(*opt == int('a'), "");
}
{
std::string s("123");
auto opt = make_optional<std::string>(s);
assert(*opt == s);
}
{
std::unique_ptr<int> s(new int(3));
auto opt = make_optional<std::unique_ptr<int>>(std::move(s));
assert(**opt == 3);
assert(s == nullptr);
}
{
auto opt = make_optional<std::string>(4, 'X');
assert(*opt == "XXXX");
}
}
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