Files
AQuery/server/hasher.h
T
2022-06-09 15:34:25 +08:00

21 lines
695 B
C++

#pragma once
#include <functional>
#include <tuple>
template <class ...Types>
struct hasher {
template <size_t i = 0> typename std::enable_if< i == sizeof...(Types),
size_t>::type hashi(const std::tuple<Types...>& record) const {
return 0;
}
template <size_t i = 0> typename std::enable_if< i < sizeof ...(Types),
size_t>::type hashi(const std::tuple<Types...>& record) const {
using current_type = typename std::decay<typename std::tuple_element<i, std::tuple<Types...>>::type>::type;
return std::hash<current_type>()(std::get<i>(record)) ^ hashi<i+1>(record);
}
size_t operator()(const std::tuple<Types...>& record) const {
return hashi(record);
}
};