Sprout/sprout/weed/detail/is_tuple_and_elem.hpp
2019-01-07 17:47:17 +09:00

40 lines
1.3 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_WEED_DETAIL_IS_TUPLE_AND_ELEM_HPP
#define SPROUT_WEED_DETAIL_IS_TUPLE_AND_ELEM_HPP
#include <type_traits>
#include <sprout/config.hpp>
#include <sprout/type_traits/integral_constant.hpp>
#include <sprout/weed/traits/type/is_tuple.hpp>
#include <sprout/weed/traits/type/is_unused.hpp>
namespace sprout {
namespace weed {
namespace detail {
template<typename T, typename U, typename = void>
struct is_tuple_and_elem
: public sprout::false_type
{};
template<typename T, typename U>
struct is_tuple_and_elem<
T,
U,
typename std::enable_if<
sprout::weed::traits::is_tuple<T>::value
&& !sprout::weed::traits::is_tuple<U>::value
&& !sprout::weed::traits::is_unused<U>::value
>::type
>
: public sprout::true_type
{};
} // namespace detail
} // namespace weed
} // namespace sprout
#endif // #ifndef SPROUT_WEED_DETAIL_IS_TUPLE_AND_ELEM_HPP