src/hotspot/share/utilities/tuple.hpp

/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
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* 2 along with this work; if not, write to the Free Software Foundation,
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#ifndef SHARE_UTILITIES_TUPLE_HPP
#define SHARE_UTILITIES_TUPLE_HPP

#include <type_traits>

template <class... Ts>
class Tuple;

template <>
class Tuple<> {};

template <class T, class... Ts>
class Tuple<T, Ts...> {
private:
  T _first;
  Tuple<Ts...> _remaining;

public:
  constexpr Tuple(const T& first, const Ts&... remaining) noexcept
    : _first(first), _remaining(remaining...) {}

  template <std::size_t I, std::enable_if_t<(I > 0), int> = 0>
  constexpr const auto& get() const noexcept {
    return _remaining.template get<I - 1>();
  };

  template <std::size_t I, std::enable_if_t<I == 0, int> = 0>
  constexpr const T& get() const noexcept {
    return _first;
  }
};

#endif // SHARE_UTILITIES_TUPLE_HPP