<functional> Support

The following functions from <functional> are overloaded:

#include <boost/decimal/hash.hpp>

namespace std {

template <>
struct hash<boost::decimal::decimal32_t>;

template <>
struct hash<boost::decimal::decimal_fast32_t>;

template <>
struct hash<boost::decimal::decimal64_t>;

template <>
struct hash<boost::decimal::decimal_fast64_t>;

template <>
struct hash<boost::decimal::decimal128_t>;

template <>
struct hash<boost::decimal::decimal_fast128_t>;

} //namespace std

The same header also gives hash_value overloads, which boost::hash finds by argument-dependent lookup. So the containers of Boost.Unordered accept the decimal types as keys with their default hasher. Each overload gives the same value as the matching std::hash specialization.

#include <boost/decimal/hash.hpp>

namespace boost {
namespace decimal {

std::size_t hash_value(const decimal32_t& v) noexcept;

std::size_t hash_value(const decimal_fast32_t& v) noexcept;

std::size_t hash_value(const decimal64_t& v) noexcept;

std::size_t hash_value(const decimal_fast64_t& v) noexcept;

std::size_t hash_value(const decimal128_t& v) noexcept;

std::size_t hash_value(const decimal_fast128_t& v) noexcept;

} //namespace decimal
} //namespace boost
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