Sprout/sprout/tpp/algorithm/max_element.hpp
2016-02-25 18:48:28 +09:00

54 lines
1.9 KiB
C++

/*=============================================================================
Copyright (c) 2011-2016 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_TPP_ALGORITHM_MAX_ELEMENT_HPP
#define SPROUT_TPP_ALGORITHM_MAX_ELEMENT_HPP
#include <type_traits>
#include <sprout/config.hpp>
#include <sprout/workaround/std/cstddef.hpp>
#include <sprout/type_traits/integral_constant.hpp>
#include <sprout/type/type_tuple.hpp>
namespace sprout {
namespace tpp {
namespace detail {
template<typename T, typename U>
struct max_value
: public std::conditional<(T::value < U::value), U, T>
{};
template<typename Tup, std::size_t First, std::size_t Last, bool = (Last - First == 1)>
struct max_element_impl
: public std::tuple_element<First, Tup>::type
{};
template<typename Tup, std::size_t First, std::size_t Last>
struct max_element_impl<Tup, First, Last, false>
: public sprout::tpp::detail::max_value<
typename sprout::tpp::detail::max_element_impl<Tup, First, (First + Last) / 2>::type,
typename sprout::tpp::detail::max_element_impl<Tup, (First + Last) / 2, Last>::type
>::type
{};
} // namespace detail
//
// max_element
//
template<typename... Types>
struct max_element
: public sprout::tpp::detail::max_element_impl<sprout::types::type_tuple<Types...>, 0, sizeof...(Types)>
{};
//
// max_element_c
//
template<typename T, T... Values>
struct max_element_c
: public sprout::tpp::max_element<sprout::integral_constant<T, Values>...>
{};
} // namespace tpp
} // namespace sprout
#endif // #ifndef SPROUT_TPP_ALGORITHM_MAX_ELEMENT_HPP