/*
** Copyright (C) 2019-2020 Dirk-Jan C. Binnema <djcb@djcbsoftware.nl>
**
** This program is free software; you can redistribute it and/or modify it
** under the terms of the GNU General Public License as published by the
** Free Software Foundation; either version 3, or (at your option) any
** later version.
**
** 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 General Public License for more details.
**
** You should have received a copy of the GNU General Public License
** along with this program; if not, write to the Free Software Foundation,
** Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
**
*/

#ifndef MU_RESULT_HH__
#define MU_RESULT_HH__

#include "expected.hpp"
#include "utils/mu-error.hh"

namespace Mu {
/**
 * A little Rust-envy...a Result is _either_ some value of type T, _or_ a Mu::Error
 */
template <typename T> using Result = tl::expected<T, Error>;

/**
 * Ok() is not typically strictly needed (unlike Err), but imitates Rust's Ok
 * and it helps the reader.
 *
 * @param t the value to return
 *
 * @return a success Result<T>
 */
template <typename T>
typename Result<T>::expected
Ok(T&& t)
{
	return std::move(t);
}

/**
 * Implementation of Ok() for void results.
 *
 * @return a success Result<void>
 */
static inline Result<void>
Ok()
{
	return {};
}

/**
 * Return an error
 *
 * @param err the error
 *
 * @return error
 */
static inline tl::unexpected<Error>
Err(Error&& err)
{
	return tl::unexpected(std::move(err));
}

static inline tl::unexpected<Error>
Err(const Error& err)
{
	return tl::unexpected(err);
}

} // namespace Mu


#endif /* MU_RESULT_HH__ */