整理

include/boost/container_hash/detail/hash_tuple_like.hpp

@@ -0,0 +1,62 @@
+// Copyright 2005-2009 Daniel James.
+// Copyright 2021 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#ifndef BOOST_HASH_DETAIL_HASH_TUPLE_LIKE_HPP
+#define BOOST_HASH_DETAIL_HASH_TUPLE_LIKE_HPP
+
+#include <boost/container_hash/hash_fwd.hpp>
+#include <boost/container_hash/is_tuple_like.hpp>
+#include <boost/container_hash/is_range.hpp>
+#include <type_traits>
+#include <utility>
+
+namespace boost
+{
+namespace hash_detail
+{
+
+template <std::size_t I, typename T>
+inline
+typename std::enable_if<(I == std::tuple_size<T>::value), void>::type
+    hash_combine_tuple_like( std::size_t&, T const& )
+{
+}
+
+template <std::size_t I, typename T>
+inline
+typename std::enable_if<(I < std::tuple_size<T>::value), void>::type
+    hash_combine_tuple_like( std::size_t& seed, T const& v )
+{
+    using std::get;
+    boost::hash_combine( seed, get<I>( v ) );
+
+    boost::hash_detail::hash_combine_tuple_like<I + 1>( seed, v );
+}
+
+template <typename T>
+inline std::size_t hash_tuple_like( T const& v )
+{
+    std::size_t seed = 0;
+
+    boost::hash_detail::hash_combine_tuple_like<0>( seed, v );
+
+    return seed;
+}
+
+} // namespace hash_detail
+
+template <class T>
+inline
+typename std::enable_if<
+    container_hash::is_tuple_like<T>::value && !container_hash::is_range<T>::value,
+std::size_t>::type
+    hash_value( T const& v )
+{
+    return boost::hash_detail::hash_tuple_like( v );
+}
+
+} // namespace boost
+
+#endif // #ifndef BOOST_HASH_DETAIL_HASH_TUPLE_LIKE_HPP