Sprout/sprout/tuple/operation/append_front.hpp
2019-01-07 17:47:17 +09:00

60 lines
2.1 KiB
C++

/*=============================================================================
Copyright (c) 2011-2019 Bolero MURAKAMI
https://github.com/bolero-MURAKAMI/Sprout
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
=============================================================================*/
#ifndef SPROUT_TUPLE_OPERATION_APPEND_FRONT_HPP
#define SPROUT_TUPLE_OPERATION_APPEND_FRONT_HPP
#include <sprout/config.hpp>
#include <sprout/index_tuple/metafunction.hpp>
#include <sprout/tuple/tuple.hpp>
#include <sprout/tuple/functions.hpp>
#include <sprout/tuple/indexes.hpp>
#include <sprout/type/operation/append_front.hpp>
namespace sprout {
namespace tuples {
namespace results {
//
// append_front
//
template<typename Tuple, typename InputTuple>
struct append_front
: public sprout::types::append_front<Tuple, InputTuple>
{};
} // namespace results
namespace detail {
template<typename Result, typename Tuple, typename InputTuple, sprout::index_t... Indexes1, sprout::index_t... Indexes2>
inline SPROUT_CONSTEXPR Result
append_front_impl(
Tuple const& t, InputTuple const& input,
sprout::index_tuple<Indexes1...>, sprout::index_tuple<Indexes2...>
)
{
return sprout::tuples::remake<Result>(
t,
sprout::tuples::get<Indexes2>(input)...,
sprout::tuples::get<Indexes1>(t)...
);
}
} // namespace detail
//
// append_front
//
template<typename Tuple, typename InputTuple>
inline SPROUT_CONSTEXPR typename sprout::tuples::results::append_front<Tuple, InputTuple>::type
append_front(Tuple const& t, InputTuple const& input) {
return sprout::tuples::detail::append_front_impl<typename sprout::tuples::results::append_front<Tuple, InputTuple>::type>(
t, input,
sprout::tuple_indexes<Tuple>::make(),
sprout::tuple_indexes<InputTuple>::make()
);
}
} // namespace tuples
} // namespace sprout
#endif // #ifndef SPROUT_TUPLE_OPERATION_APPEND_FRONT_HPP