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/*
* Copyright (C) 2015 Canonical Ltd.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License version 3 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* Authored by: Michi Henning <michi.henning@canonical.com>
*/
#pragma once
#include <boost/optional.hpp>
// std::optional doesn't support operator<< so core::Optional users shouldn't
// expect it to be available. However, consumers (e.g. GoogleTest) can
// auto-detect this operator using "ADL", so without including
// boost/optional/optional_io.hpp they will detect the non-working one which
// breaks the build.
#include <boost/optional/optional_io.hpp>
namespace core
{
/**
\brief Convenience typedef for nullable values.
\note You should use `core::Optional` in preference to `boost::optional`
in your code. This will ease an eventual transition to `std::optional`.
*/
template <typename T>
using Optional = boost::optional<T>;
} // namespace core
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