mirror of
https://github.com/bolero-MURAKAMI/Sprout.git
synced 2024-12-23 21:25:49 +00:00
44 lines
1.6 KiB
C++
44 lines
1.6 KiB
C++
/*=============================================================================
|
|
Copyright (c) 2011-2014 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_FUNCTIONAL_HASH_HASH_COMBINE_HPP
|
|
#define SPROUT_FUNCTIONAL_HASH_HASH_COMBINE_HPP
|
|
|
|
#include <cstddef>
|
|
#include <sprout/config.hpp>
|
|
#include <sprout/functional/hash/hash_fwd.hpp>
|
|
#include <sprout/functional/hash/to_hash.hpp>
|
|
|
|
namespace sprout {
|
|
namespace detail {
|
|
template<typename T>
|
|
inline SPROUT_CONSTEXPR std::size_t
|
|
hash_combine_impl(std::size_t seed) {
|
|
return seed;
|
|
}
|
|
template<typename T>
|
|
inline SPROUT_CONSTEXPR std::size_t
|
|
hash_combine_impl(std::size_t seed, T const& v) {
|
|
return seed ^ (sprout::to_hash(v) + 0x9e3779b9 + (seed << 6) + (seed >> 2));
|
|
}
|
|
template<typename Head, typename... Tail>
|
|
inline SPROUT_CONSTEXPR std::size_t
|
|
hash_combine_impl(std::size_t seed, Head const& head, Tail const&... tail) {
|
|
return sprout::detail::hash_combine_impl(sprout::detail::hash_combine_impl(seed, head), tail...);
|
|
}
|
|
} // namespace detail
|
|
//
|
|
// hash_combine
|
|
//
|
|
template<typename... Args>
|
|
inline SPROUT_CONSTEXPR std::size_t
|
|
hash_combine(std::size_t seed, Args const&... args) {
|
|
return sprout::detail::hash_combine_impl(seed, args...);
|
|
}
|
|
} // namespace sprout
|
|
|
|
#endif // #ifndef SPROUT_FUNCTIONAL_HASH_HASH_COMBINE_HPP
|