Standard library header <chrono> (C++11)

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이 헤더는 날짜 및 시간 라이브러리의 일부입니다.

함수
Duration
정의된 네임스페이스 `std::chrono`
operator+ operator- operator* operator/ operator% (C++11)	duration을 인자로 사용하는 산술 연산 구현 (함수 템플릿)
operator== operator!= operator< operator<= operator> operator>= operator<=> (C++11) (C++11) (C++20에서 제거됨) (C++11) (C++11) (C++11) (C++11) (C++20)	두 지속 시간을 비교함 (함수 템플릿)
duration_cast (C++11)	다른 틱 간격을 가진 duration으로 변환합니다 (함수 템플릿)
floor (std::chrono::duration) (C++17)	duration을 다른 단위로 변환하며 내림 처리 (함수 템플릿)
ceil (std::chrono::duration) (C++17)	duration을 다른 단위로 변환하며 올림 처리 (함수 템플릿)
round (std::chrono::duration) (C++17)	duration을 다른 단위로 변환하며, 가장 가까운 값으로 반올림(동점 시 짝수로) (함수 템플릿)
abs (std::chrono::duration) (C++17)	기간의 절댓값을 구함 (함수 템플릿)
타임 포인트
정의된 네임스페이스 `std::chrono`
operator+ operator- (C++11)	time point와 관련된 덧셈 및 뺄셈 연산 수행 (함수 템플릿)
operator== operator!= operator< operator<= operator> operator>= operator<=> (C++11) (C++11) (C++20에서 제거됨) (C++11) (C++11) (C++11) (C++11) (C++20)	두 시간 포인트를 비교함 (함수 템플릿)
time_point_cast (C++11)	동일한 클록 상에서 다른 duration을 가진 시간 포인트로 변환합니다 (함수 템플릿)
floor (std::chrono::time_point) (C++17)	time_point를 다른 단위로 변환하며 내림 처리 (함수 템플릿)
ceil (std::chrono::time_point) (C++17)	time_point를 다른 단위로 변환하며 올림 처리 (함수 템플릿)
round (std::chrono::time_point) (C++17)	time_point를 다른 단위로 변환하며, 가장 가까운 값으로 반올림(동점 시 짝수로 처리) (함수 템플릿)
from_stream (std::chrono::sys_time) (C++20)	제공된 형식에 따라 스트림에서 `sys_time` 을 파싱합니다 (함수 템플릿)
from_stream (std::chrono::utc_time) (C++20)	제공된 형식에 따라 스트림에서 `utc_time` 을 파싱합니다 (함수 템플릿)
from_stream (std::chrono::tai_time) (C++20)	제공된 형식에 따라 스트림에서 `tai_time` 을 파싱합니다 (함수 템플릿)
from_stream (std::chrono::gps_time) (C++20)	제공된 형식에 따라 스트림에서 `gps_time` 을 파싱합니다 (함수 템플릿)
from_stream (std::chrono::file_time) (C++20)	제공된 형식에 따라 스트림에서 `file_time` 을 파싱합니다 (함수 템플릿)
from_stream (std::chrono::local_time) (C++20)	제공된 형식에 따라 스트림에서 `local_time` 을 파싱합니다 (함수 템플릿)
clock_cast (C++20)	한 클록의 시간 포인트를 다른 클록으로 변환 (함수 템플릿)
캘린더
정의된 네임스페이스 `std::chrono`
operator== operator<=> (C++20)	두 `day` 값을 비교 (함수)
operator== operator<=> (C++20)	두 개의 `month` 값을 비교 (함수)
operator== operator<=> (C++20)	두 `year` 값을 비교 (함수)
operator== (C++20)	두 `weekday` 값을 비교 (함수)
operator== (C++20)	두 `weekday_indexed` 값을 비교 (함수)
operator== (C++20)	두 `weekday_last` 값을 비교합니다 (함수)
operator== operator<=> (C++20)	두 `month_day` 값을 비교 (함수)
operator== operator<=> (C++20)	두 `month_day_last` 값을 비교 (함수)
operator== (C++20)	두 `month_weekday` 값을 비교 (함수)
operator== (C++20)	두 개의 `month_weekday_last` 값을 비교함 (함수)
operator== operator<=> (C++20)	두 개의 `year_month` 값을 비교합니다 (함수)
operator== operator<=> (C++20)	두 `year_month_day` 값을 비교 (함수)
operator== operator<=> (C++20)	두 개의 `year_month_day_last` 값을 비교합니다 (함수)
operator== (C++20)	두 `year_month_weekday` 값을 비교 (함수)
operator== (C++20)	두 개의 `year_month_weekday_last` 값을 비교합니다 (함수)
operator+ operator- (C++20)	일 수와 `day` 를 더하거나 빼거나, 두 `day` 사이의 차이를 구함 (함수)
operator+ operator- (C++20)	`month` 에 대한 산술 연산 수행 (함수)
operator+ operator- (C++20)	`year` 에 대한 산술 연산 수행 (함수)
operator+ operator- (C++20)	`weekday` 에 대한 산술 연산 수행 (함수)
operator+ operator- (C++20)	`year_month` 에 대한 산술 연산 수행 (함수)
operator+ operator- (C++20)	`year_month_day` 와 일정 년수 또는 월수를 더하거나 뺌 (함수)
operator+ operator- (C++20)	`year_month_day_last` 와 일부 연수 또는 월수를 더하거나 뺌 (함수)
operator+ operator- (C++20)	`year_month_weekday` 에 연수나 월수를 더하거나 뺌 (함수)
operator+ operator- (C++20)	`year_month_weekday_last` 와 일부 연수 또는 월수를 더하거나 뺌 (함수)
operator/ (C++20)	그레고리력 날짜 생성을 위한 관용적 구문 (함수)
시간대
정의된 네임스페이스 `std::chrono`
is_am is_pm make12 make24 (C++20)	12시간/24시간 형식의 시간을 상호 변환 (함수)
시간대
정의된 네임스페이스 `std::chrono`
get_tzdb get_tzdb_list reload_tzdb remote_version (C++20)	전역 시간대 데이터베이스 정보에 접근하고 제어합니다 (함수)
locate_zone (C++20)	이름을 기반으로 `time_zone` 을 찾습니다 (함수)
operator== operator<=> (C++20)	두 `time_zone` 객체를 비교합니다 (함수)
operator== (C++20)	두 `zoned_time` 값을 비교합니다 (함수 템플릿)
operator== operator<=> (C++20)	두 개의 `time_zone_link` 객체를 비교합니다 (함수)
윤초
정의된 네임스페이스 `std::chrono`
get_leap_second_info (C++20)	`utc_time` 객체에서 윤초 삽입 정보를 획득합니다 (함수 템플릿)
operator== operator< operator<= operator> operator>= operator<=> (C++20)	두 `leap_second` 값을 비교하거나 `leap_second` 값과 sys_time 을 비교합니다 (함수 템플릿)
입출력
정의된 네임스페이스 `std::chrono`
operator<< (C++20)	`duration` 에 대한 스트림 출력을 수행합니다 (함수 템플릿)
operator<< (std::chrono::sys_time) (C++20)	`sys_time` 에 대한 스트림 출력을 수행합니다 (함수 템플릿)
operator<< (std::chrono::utc_time) (C++20)	`utc_time` 에 대한 스트림 출력을 수행합니다 (함수 템플릿)
operator<< (std::chrono::tai_time) (C++20)	`tai_time` 에 대한 스트림 출력을 수행합니다 (함수 템플릿)
operator<< (std::chrono::gps_time) (C++20)	`gps_time` 에 대한 스트림 출력을 수행합니다 (함수 템플릿)
operator<< (std::chrono::file_time) (C++20)	`file_time` 에 대한 스트림 출력을 수행합니다 (함수 템플릿)
operator<< (C++20)	스트림에 `day` 를 출력합니다 (함수 템플릿)
operator<< (C++20)	스트림에 `month` 를 출력합니다 (함수 템플릿)
operator<< (C++20)	스트림에 `year` 를 출력합니다 (함수 템플릿)
operator<< (C++20)	스트림에 `weekday` 를 출력합니다 (함수 템플릿)
operator<< (C++20)	스트림에 `weekday_indexed` 출력 (함수 템플릿)
operator<< (C++20)	`weekday_last` 를 스트림으로 출력 (함수 템플릿)
operator<< (C++20)	`month_day` 를 스트림으로 출력 (함수 템플릿)
operator<< (C++20)	`month_day_last` 를 스트림으로 출력합니다 (함수 템플릿)
operator<< (C++20)	`month_weekday` 를 스트림으로 출력합니다 (함수 템플릿)
operator<< (C++20)	스트림에 `month_weekday_last` 출력 (함수 템플릿)
operator<< (C++20)	스트림에 `year_month` 를 출력합니다 (함수 템플릿)
operator<< (C++20)	`year_month_day` 를 스트림으로 출력합니다 (함수 템플릿)
operator<< (C++20)	스트림에 `year_month_day_last` 를 출력합니다 (함수 템플릿)
operator<< (C++20)	스트림에 `year_month_weekday` 를 출력합니다 (함수 템플릿)
operator<< (C++20)	`year_month_weekday_last` 를 스트림으로 출력 (함수 템플릿)
operator<< (C++20)	스트림에 `hh_mm_ss` 출력 (함수 템플릿)
operator<< (C++20)	스트림에 `sys_info` 를 출력합니다 (함수 템플릿)
operator<< (C++20)	`local_info` 를 스트림으로 출력 (함수 템플릿)
operator<< (C++20)	`zoned_time` 을 스트림으로 출력 (함수 템플릿)
from_stream (C++20)	제공된 형식에 따라 스트림에서 `day` 를 파싱합니다 (함수 템플릿)
from_stream (C++20)	제공된 형식에 따라 스트림에서 `month` 를 파싱합니다 (함수 템플릿)
from_stream (C++20)	제공된 형식에 따라 스트림에서 `year` 을 파싱합니다 (함수 템플릿)
from_stream (C++20)	제공된 형식에 따라 스트림에서 `weekday` 를 파싱합니다 (함수 템플릿)
from_stream (C++20)	제공된 형식에 따라 스트림에서 `month_day` 를 파싱합니다 (함수 템플릿)
from_stream (C++20)	제공된 형식에 따라 스트림에서 `year_month` 를 파싱합니다 (함수 템플릿)
from_stream (C++20)	제공된 형식에 따라 스트림에서 `year_month_day` 를 파싱합니다 (함수 템플릿)
parse (C++20)	스트림에서 `chrono` 객체를 파싱합니다 (함수 템플릿)
리터럴
인라인 네임스페이스 `std::literals::chrono_literals` 에서 정의됨
operator""h (C++14)	시간을 나타내는 std::chrono::duration 리터럴 (함수)
operator""min (C++14)	분을 나타내는 std::chrono::duration 리터럴 (함수)
operator""s (C++14)	초를 나타내는 std::chrono::duration 리터럴 (함수)
operator""ms (C++14)	밀리초를 나타내는 std::chrono::duration 리터럴 (함수)
operator""us (C++14)	마이크로초를 나타내는 std::chrono::duration 리터럴 (함수)
operator""ns (C++14)	나노초를 나타내는 std::chrono::duration 리터럴 (함수)
operator""d (C++20)	월의 날짜를 나타내는 std::chrono::day 리터럴 (함수)
operator""y (C++20)	특정 연도를 나타내는 std::chrono::year 리터럴 (함수)

시놉시스

#include <compare>
namespace std {
  namespace chrono {
    // 클래스 템플릿 duration
    template<class Rep, class Period = ratio<1>> class duration;
    // 클래스 템플릿 time_point
    template<class Clock, class Duration = typename Clock::duration> class time_point;
  }
  // common_type 특수화
  template<class Rep1, class Period1, class Rep2, class Period2>
    struct common_type<chrono::duration<Rep1, Period1>,
                       chrono::duration<Rep2, Period2>>;
  template<class Clock, class Duration1, class Duration2>
    struct common_type<chrono::time_point<Clock, Duration1>,
                       chrono::time_point<Clock, Duration2>>;
  namespace chrono {
    // customization traits
    template<class Rep> struct treat_as_floating_point;
    template<class Rep>
      inline constexpr bool treat_as_floating_point_v = treat_as_floating_point<Rep>::value;
    template<class Rep> struct duration_values;
    template<class T> struct is_clock;
    template<class T> inline constexpr bool is_clock_v = is_clock<T>::value;
    // duration arithmetic
    template<class Rep1, class Period1, class Rep2, class Period2>
      constexpr common_type_t<duration<Rep1, Period1>, duration<Rep2, Period2>>
        operator+(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
    template<class Rep1, class Period1, class Rep2, class Period2>
      constexpr common_type_t<duration<Rep1, Period1>, duration<Rep2, Period2>>
        operator-(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
    template<class Rep1, class Period, class Rep2>
      constexpr duration<common_type_t<Rep1, Rep2>, Period>
        operator*(const duration<Rep1, Period>& d, const Rep2& s);
    template<class Rep1, class Rep2, class Period>
      constexpr duration<common_type_t<Rep1, Rep2>, Period>
        operator*(const Rep1& s, const duration<Rep2, Period>& d);
    template<class Rep1, class Period, class Rep2>
      constexpr duration<common_type_t<Rep1, Rep2>, Period>
        operator/(const duration<Rep1, Period>& d, const Rep2& s);
    template<class Rep1, class Period1, class Rep2, class Period2>
      constexpr common_type_t<Rep1, Rep2>
        operator/(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
    template<class Rep1, class Period, class Rep2>
      constexpr duration<common_type_t<Rep1, Rep2>, Period>
        operator%(const duration<Rep1, Period>& d, const Rep2& s);
    template<class Rep1, class Period1, class Rep2, class Period2>
      constexpr common_type_t<duration<Rep1, Period1>, duration<Rep2, Period2>>
        operator%(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
    // duration comparisons
    template<class Rep1, class Period1, class Rep2, class Period2>
      constexpr bool operator==(const duration<Rep1, Period1>& lhs,
                                const duration<Rep2, Period2>& rhs);
    template<class Rep1, class Period1, class Rep2, class Period2>
      constexpr bool operator< (const duration<Rep1, Period1>& lhs,
                                const duration<Rep2, Period2>& rhs);
    template<class Rep1, class Period1, class Rep2, class Period2>
      constexpr bool operator> (const duration<Rep1, Period1>& lhs,
                                const duration<Rep2, Period2>& rhs);
    template<class Rep1, class Period1, class Rep2, class Period2>
      constexpr bool operator<=(const duration<Rep1, Period1>& lhs,
                                const duration<Rep2, Period2>& rhs);
    template<class Rep1, class Period1, class Rep2, class Period2>
      constexpr bool operator>=(const duration<Rep1, Period1>& lhs,
                                const duration<Rep2, Period2>& rhs);
    template<class Rep1, class Period1, class Rep2, class Period2>
      requires /* 설명 참조 */
      constexpr auto operator<=>(const duration<Rep1, Period1>& lhs,
                                 const duration<Rep2, Period2>& rhs);
    // 변환
    template<class ToDuration, class Rep, class Period>
      constexpr ToDuration duration_cast(const duration<Rep, Period>& d);
    template<class ToDuration, class Rep, class Period>
      constexpr ToDuration floor(const duration<Rep, Period>& d);
    template<class ToDuration, class Rep, class Period>
      constexpr ToDuration ceil(const duration<Rep, Period>& d);
    template<class ToDuration, class Rep, class Period>
      constexpr ToDuration round(const duration<Rep, Period>& d);
    // duration I/O
    template<class CharT, class Traits, class Rep, class Period>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os,
                   const duration<Rep, Period>& d);
    template<class CharT, class Traits, class Rep, class Period, class Alloc = allocator<CharT>>
      basic_istream<CharT, Traits>&
        from_stream(basic_istream<CharT, Traits>& is, const CharT* fmt,
                    duration<Rep, Period>& d,
                    basic_string<CharT, Traits, Alloc>* abbrev = nullptr,
                    minutes* offset = nullptr);
    // 편의성을 위한 typedefs
    using nanoseconds  = duration</* 최소 64비트 크기의 부호 있는 정수형 */, nano>;
    using microseconds = duration</* 최소 55비트 크기의 부호 있는 정수형 */, micro>;
    using milliseconds = duration</* 최소 45비트 크기의 부호 있는 정수형 */, milli>;
    using seconds      = duration</* 최소 35비트 크기의 부호 있는 정수형 */>;
    using minutes      = duration</* 최소 29비트의 부호 있는 정수형 */,
                                  ratio<  60>>;
    using hours        = duration</* 최소 23비트의 부호 있는 정수형 */,
                                  ratio<3600>>;
    using days         = duration</* 최소 25비트의 부호 있는 정수형 */,
                                  ratio_multiply<ratio<24>, hours::period>>;
    using weeks        = duration</* 최소 22비트의 부호 있는 정수형 */,
                                  ratio_multiply<ratio<7>, days::period>>;
    using years        = duration</* 최소 17비트 크기의 부호 있는 정수형 */,
                                  ratio_multiply<ratio<146097, 400>, days::period>>;
    using months       = duration</* 최소 20비트 크기의 부호 있는 정수형 */,
                                  ratio_divide<years::period, ratio<12>>>;
    // time_point 연산
    template<class Clock, class Duration1, class Rep2, class Period2>
      constexpr time_point<Clock, common_type_t<Duration1, duration<Rep2, Period2>>>
        operator+(const time_point<Clock, Duration1>& lhs, const duration<Rep2, Period2>& rhs);
    template<class Rep1, class Period1, class Clock, class Duration2>
      constexpr time_point<Clock, common_type_t<duration<Rep1, Period1>, Duration2>>
        operator+(const duration<Rep1, Period1>& lhs, const time_point<Clock, Duration2>& rhs);
    template<class Clock, class Duration1, class Rep2, class Period2>
      constexpr time_point<Clock, common_type_t<Duration1, duration<Rep2, Period2>>>
        operator-(const time_point<Clock, Duration1>& lhs, const duration<Rep2, Period2>& rhs);
    template<class Clock, class Duration1, class Duration2>
      constexpr common_type_t<Duration1, Duration2>
        operator-(const time_point<Clock, Duration1>& lhs,
                  const time_point<Clock, Duration2>& rhs);
    // time_point 비교
    template<class Clock, class Duration1, class Duration2>
       constexpr bool operator==(const time_point<Clock, Duration1>& lhs,
                                 const time_point<Clock, Duration2>& rhs);
    template<class Clock, class Duration1, class Duration2>
       constexpr bool operator< (const time_point<Clock, Duration1>& lhs,
                                 const time_point<Clock, Duration2>& rhs);
    template<class Clock, class Duration1, class Duration2>
       constexpr bool operator> (const time_point<Clock, Duration1>& lhs,
                                 const time_point<Clock, Duration2>& rhs);
    template<class Clock, class Duration1, class Duration2>
       constexpr bool operator<=(const time_point<Clock, Duration1>& lhs,
                                 const time_point<Clock, Duration2>& rhs);
    template<class Clock, class Duration1, class Duration2>
       constexpr bool operator>=(const time_point<Clock, Duration1>& lhs,
                                 const time_point<Clock, Duration2>& rhs);
    template<class Clock, class Duration1, three_way_comparable_with<Duration1> Duration2>
       constexpr auto operator<=>(const time_point<Clock, Duration1>& lhs,
                                  const time_point<Clock, Duration2>& rhs);
    // 변환
    template<class ToDuration, class Clock, class Duration>
      constexpr time_point<Clock, ToDuration>
        time_point_cast(const time_point<Clock, Duration>& t);
    template<class ToDuration, class Clock, class Duration>
      constexpr time_point<Clock, ToDuration> floor(const time_point<Clock, Duration>& tp);
    template<class ToDuration, class Clock, class Duration>
      constexpr time_point<Clock, ToDuration> ceil(const time_point<Clock, Duration>& tp);
    template<class ToDuration, class Clock, class Duration>
      constexpr time_point<Clock, ToDuration> round(const time_point<Clock, Duration>& tp);
    // 특수화된 알고리즘
    template<class Rep, class Period>
      constexpr duration<Rep, Period> abs(duration<Rep, Period> d);
    // class system_clock
    class system_clock;
    template<class Duration>
      using sys_time  = time_point<system_clock, Duration>;
    using sys_seconds = sys_time<seconds>;
    using sys_days    = sys_time<days>;
    template<class CharT, class Traits, class Duration>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const sys_time<Duration>& tp);
    template<class CharT, class Traits>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const sys_days& dp);
    template<class CharT, class Traits, class Duration, class Alloc = allocator<CharT>>
      basic_istream<CharT, Traits>&
        from_stream(basic_istream<CharT, Traits>& is, const CharT* fmt,
                    sys_time<Duration>& tp,
                    basic_string<CharT, Traits, Alloc>* abbrev = nullptr,
                    minutes* offset = nullptr);
    // class utc_clock
    class utc_clock;
    template<class Duration>
      using utc_time  = time_point<utc_clock, Duration>;
    using utc_seconds = utc_time<seconds>;
    template<class CharT, class Traits, class Duration>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const utc_time<Duration>& t);
    template<class CharT, class Traits, class Duration, class Alloc = allocator<CharT>>
      basic_istream<CharT, Traits>&
        from_stream(basic_istream<CharT, Traits>& is, const CharT* fmt,
                    utc_time<Duration>& tp,
                    basic_string<CharT, Traits, Alloc>* abbrev = nullptr,
                    minutes* offset = nullptr);
    struct leap_second_info;
    template<class Duration>
      leap_second_info get_leap_second_info(const utc_time<Duration>& ut);
    // class tai_clock
    class tai_clock;
    template<class Duration>
      using tai_time  = time_point<tai_clock, Duration>;
    using tai_seconds = tai_time<seconds>;
    template<class CharT, class Traits, class Duration>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const tai_time<Duration>& t);
    template<class CharT, class Traits, class Duration, class Alloc = allocator<CharT>>
      basic_istream<CharT, Traits>&
        from_stream(basic_istream<CharT, Traits>& is, const CharT* fmt,
                    tai_time<Duration>& tp,
                    basic_string<CharT, Traits, Alloc>* abbrev = nullptr,
                    minutes* offset = nullptr);
    // class gps_clock
    class gps_clock;
    template<class Duration>
      using gps_time  = time_point<gps_clock, Duration>;
    using gps_seconds = gps_time<seconds>;
    template<class CharT, class Traits, class Duration>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const gps_time<Duration>& t);
    template<class CharT, class Traits, class Duration, class Alloc = allocator<CharT>>
      basic_istream<CharT, Traits>&
        from_stream(basic_istream<CharT, Traits>& is, const CharT* fmt,
                    gps_time<Duration>& tp,
                    basic_string<CharT, Traits, Alloc>* abbrev = nullptr,
                    minutes* offset = nullptr);
    // type file_clock
    using file_clock = /* 설명 참조 */;
    template<class Duration>
      using file_time = time_point<file_clock, Duration>;
    template<class CharT, class Traits, class Duration>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const file_time<Duration>& tp);
    template<class CharT, class Traits, class Duration, class Alloc = allocator<CharT>>
      basic_istream<CharT, Traits>&
        from_stream(basic_istream<CharT, Traits>& is, const CharT* fmt,
                    file_time<Duration>& tp,
                    basic_string<CharT, Traits, Alloc>* abbrev = nullptr,
                    minutes* offset = nullptr);
    // class steady_clock
    class steady_clock;
    // class high_resolution_clock
    class high_resolution_clock;
    // 로컬 시간
    struct local_t {};
    template<class Duration>
      using local_time  = time_point<local_t, Duration>;
    using local_seconds = local_time<seconds>;
    using local_days    = local_time<days>;
    template<class CharT, class Traits, class Duration>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const local_time<Duration>& tp);
    template<class CharT, class Traits, class Duration, class Alloc = allocator<CharT>>
      basic_istream<CharT, Traits>&
        from_stream(basic_istream<CharT, Traits>& is, const CharT* fmt,
                    local_time<Duration>& tp,
                    basic_string<CharT, Traits, Alloc>* abbrev = nullptr,
                    minutes* offset = nullptr);
    // time_point 변환
    template<class DestClock, class SourceClock>
      struct clock_time_conversion;
    template<class DestClock, class SourceClock, class Duration>
      auto clock_cast(const time_point<SourceClock, Duration>& t);
    // class last_spec
    struct last_spec;
    // class day
    class day;
    constexpr bool operator==(const day& x, const day& y) noexcept;
    constexpr strong_ordering operator<=>(const day& x, const day& y) noexcept;
    constexpr day  operator+(const day&  x, const days& y) noexcept;
    constexpr day  operator+(const days& x, const day&  y) noexcept;
    constexpr day  operator-(const day&  x, const days& y) noexcept;
    constexpr days operator-(const day&  x, const day&  y) noexcept;
    template<class CharT, class Traits>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const day& d);
    template<class CharT, class Traits, class Alloc = allocator<CharT>>
      basic_istream<CharT, Traits>&
        from_stream(basic_istream<CharT, Traits>& is, const CharT* fmt,
                    day& d, basic_string<CharT, Traits, Alloc>* abbrev = nullptr,
                    minutes* offset = nullptr);
    // class month
    class month;
    constexpr bool operator==(const month& x, const month& y) noexcept;
    constexpr strong_ordering operator<=>(const month& x, const month& y) noexcept;
    constexpr month  operator+(const month&  x, const months& y) noexcept;
    constexpr month  operator+(const months& x,  const month& y) noexcept;
    constexpr month  operator-(const month&  x, const months& y) noexcept;
    constexpr months operator-(const month&  x,  const month& y) noexcept;
    template<class CharT, class Traits>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const month& m);
    template<class CharT, class Traits, class Alloc = allocator<CharT>>
      basic_istream<CharT, Traits>&
        from_stream(basic_istream<CharT, Traits>& is, const CharT* fmt,
                    month& m, basic_string<CharT, Traits, Alloc>* abbrev = nullptr,
                    minutes* offset = nullptr);
    // class year
    class year;
    constexpr bool operator==(const year& x, const year& y) noexcept;
    constexpr strong_ordering operator<=>(const year& x, const year& y) noexcept;
    constexpr year  operator+(const year&  x, const years& y) noexcept;
    constexpr year  operator+(const years& x, const year&  y) noexcept;
    constexpr year  operator-(const year&  x, const years& y) noexcept;
    constexpr years operator-(const year&  x, const year&  y) noexcept;
    template<class CharT, class Traits>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const year& y);
    template<class CharT, class Traits, class Alloc = allocator<CharT>>
      basic_istream<CharT, Traits>&
        from_stream(basic_istream<CharT, Traits>& is, const CharT* fmt,
                    year& y, basic_string<CharT, Traits, Alloc>* abbrev = nullptr,
                    minutes* offset = nullptr);
    // class weekday
    class weekday;
    constexpr bool operator==(const weekday& x, const weekday& y) noexcept;
    constexpr weekday operator+(const weekday& x, const days&    y) noexcept;
    constexpr weekday operator+(const days&    x, const weekday& y) noexcept;
    constexpr weekday operator-(const weekday& x, const days&    y) noexcept;
    constexpr days    operator-(const weekday& x, const weekday& y) noexcept;
    template<class CharT, class Traits>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const weekday& wd);
    template<class CharT, class Traits, class Alloc = allocator<CharT>>
      basic_istream<CharT, Traits>&
        from_stream(basic_istream<CharT, Traits>& is, const CharT* fmt,
                    weekday& wd, basic_string<CharT, Traits, Alloc>* abbrev = nullptr,
                    minutes* offset = nullptr);
    // class weekday_indexed
    class weekday_indexed;
    constexpr bool operator==(const weekday_indexed& x, const weekday_indexed& y) noexcept;
    template<class CharT, class Traits>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const weekday_indexed& wdi);
    // class weekday_last
    class weekday_last;
    constexpr bool operator==(const weekday_last& x, const weekday_last& y) noexcept;
    template<class CharT, class Traits>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const weekday_last& wdl);
    // class month_day
    class month_day;
    constexpr bool operator==(const month_day& x, const month_day& y) noexcept;
    constexpr strong_ordering operator<=>(const month_day& x, const month_day& y) noexcept;
    template<class CharT, class Traits>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const month_day& md);
    template<class CharT, class Traits, class Alloc = allocator<CharT>>
      basic_istream<CharT, Traits>&
        from_stream(basic_istream<CharT, Traits>& is, const CharT* fmt,
                    month_day& md, basic_string<CharT, Traits, Alloc>* abbrev = nullptr,
                    minutes* offset = nullptr);
    // class month_day_last
    class month_day_last;
    constexpr bool operator==(const month_day_last& x, const month_day_last& y) noexcept;
    constexpr strong_ordering operator<=>(const month_day_last& x,
                                          const month_day_last& y) noexcept;
    template<class CharT, class Traits>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const month_day_last& mdl);
    // class month_weekday
    class month_weekday;
    constexpr bool operator==(const month_weekday& x, const month_weekday& y) noexcept;
    template<class CharT, class Traits>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const month_weekday& mwd);
    // class month_weekday_last
    class month_weekday_last;
    constexpr bool operator==(const month_weekday_last& x, const month_weekday_last& y) noexcept;
    template<class CharT, class Traits>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const month_weekday_last& mwdl);
    // class year_month
    class year_month;
    constexpr bool operator==(const year_month& x, const year_month& y) noexcept;
    constexpr strong_ordering operator<=>(const year_month& x, const year_month& y) noexcept;
    constexpr year_month operator+(const year_month& ym, const months& dm) noexcept;
    constexpr year_month operator+(const months& dm, const year_month& ym) noexcept;
    constexpr year_month operator-(const year_month& ym, const months& dm) noexcept;
    constexpr months operator-(const year_month& x, const year_month& y) noexcept;
    constexpr year_month operator+(const year_month& ym, const years& dy) noexcept;
    constexpr year_month operator+(const years& dy, const year_month& ym) noexcept;
    constexpr year_month operator-(const year_month& ym, const years& dy) noexcept;
    template<class CharT, class Traits>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const year_month& ym);
    template<class CharT, class Traits, class Alloc = allocator<CharT>>
      basic_istream<CharT, Traits>&
        from_stream(basic_istream<CharT, Traits>& is, const CharT* fmt,
                    year_month& ym, basic_string<CharT, Traits, Alloc>* abbrev = nullptr,
                    minutes* offset = nullptr);
    // class year_month_day
    class year_month_day;
    constexpr bool operator==(const year_month_day& x, const year_month_day& y) noexcept;
    constexpr strong_ordering operator<=>(const year_month_day& x,
                                          const year_month_day& y) noexcept;
    constexpr year_month_day operator+(const year_month_day& ymd, const months& dm) noexcept;
    constexpr year_month_day operator+(const months& dm, const year_month_day& ymd) noexcept;
    constexpr year_month_day operator+(const year_month_day& ymd, const years& dy) noexcept;
    constexpr year_month_day operator+(const years& dy, const year_month_day& ymd) noexcept;
    constexpr year_month_day operator-(const year_month_day& ymd, const months& dm) noexcept;
    constexpr year_month_day operator-(const year_month_day& ymd, const years& dy) noexcept;
    template<class CharT, class Traits>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const year_month_day& ymd);
    template<class CharT, class Traits, class Alloc = allocator<CharT>>
      basic_istream<CharT, Traits>&
        from_stream(basic_istream<CharT, Traits>& is, const CharT* fmt,
                    year_month_day& ymd,
                    basic_string<CharT, Traits, Alloc>* abbrev = nullptr,
                    minutes* offset = nullptr);
    // class year_month_day_last
    class year_month_day_last;
    constexpr bool operator==(const year_month_day_last& x,
                              const year_month_day_last& y) noexcept;
    constexpr strong_ordering operator<=>(const year_month_day_last& x,
                                          const year_month_day_last& y) noexcept;
    constexpr year_month_day_last
      operator+(const year_month_day_last& ymdl, const months& dm) noexcept;
    constexpr year_month_day_last
      operator+(const months& dm, const year_month_day_last& ymdl) noexcept;
    constexpr year_month_day_last
      operator+(const year_month_day_last& ymdl, const years& dy) noexcept;
    constexpr year_month_day_last
      operator+(const years& dy, const year_month_day_last& ymdl) noexcept;
    constexpr year_month_day_last
      operator-(const year_month_day_last& ymdl, const months& dm) noexcept;
    constexpr year_month_day_last
      operator-(const year_month_day_last& ymdl, const years& dy) noexcept;
    template<class CharT, class Traits>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const year_month_day_last& ymdl);
    // class year_month_weekday
    class year_month_weekday;
    constexpr bool operator==(const year_month_weekday& x,
                              const year_month_weekday& y) noexcept;
    constexpr year_month_weekday
      operator+(const year_month_weekday& ymwd, const months& dm) noexcept;
    constexpr year_month_weekday
      operator+(const months& dm, const year_month_weekday& ymwd) noexcept;
    constexpr year_month_weekday
      operator+(const year_month_weekday& ymwd, const years& dy) noexcept;
    constexpr year_month_weekday
      operator+(const years& dy, const year_month_weekday& ymwd) noexcept;
    constexpr year_month_weekday
      operator-(const year_month_weekday& ymwd, const months& dm) noexcept;
    constexpr year_month_weekday
      operator-(const year_month_weekday& ymwd, const years& dy) noexcept;
    template<class CharT, class Traits>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const year_month_weekday& ymwdi);
    // class year_month_weekday_last
    class year_month_weekday_last;
    constexpr bool operator==(const year_month_weekday_last& x,
                              const year_month_weekday_last& y) noexcept;
    constexpr year_month_weekday_last
      operator+(const year_month_weekday_last& ymwdl, const months& dm) noexcept;
    constexpr year_month_weekday_last
      operator+(const months& dm, const year_month_weekday_last& ymwdl) noexcept;
    constexpr year_month_weekday_last
      operator+(const year_month_weekday_last& ymwdl, const years& dy) noexcept;
    constexpr year_month_weekday_last
      operator+(const years& dy, const year_month_weekday_last& ymwdl) noexcept;
    constexpr year_month_weekday_last
      operator-(const year_month_weekday_last& ymwdl, const months& dm) noexcept;
    constexpr year_month_weekday_last
      operator-(const year_month_weekday_last& ymwdl, const years& dy) noexcept;
    template<class CharT, class Traits>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const year_month_weekday_last& ymwdl);
    // civil calendar conventional syntax operators
    constexpr year_month
      operator/(const year& y, const month& m) noexcept;
    constexpr year_month
      operator/(const year& y, int m) noexcept;
    constexpr month_day
      operator/(const month& m, const day& d) noexcept;
    constexpr month_day
      operator/(const month& m, int d) noexcept;
    constexpr month_day
      operator/(int m, const day& d) noexcept;
    constexpr month_day
      operator/(const day& d, const month& m) noexcept;
    constexpr month_day
      operator/(const day& d, int m) noexcept;
    constexpr month_day_last
      operator/(const month& m, last_spec) noexcept;
    constexpr month_day_last
      operator/(int m, last_spec) noexcept;
    constexpr month_day_last
      operator/(last_spec, const month& m) noexcept;
    constexpr month_day_last
      operator/(last_spec, int m) noexcept;
    constexpr month_weekday
      operator/(const month& m, const weekday_indexed& wdi) noexcept;
    constexpr month_weekday
      operator/(int m, const weekday_indexed& wdi) noexcept;
    constexpr month_weekday
      operator/(const weekday_indexed& wdi, const month& m) noexcept;
    constexpr month_weekday
      operator/(const weekday_indexed& wdi, int m) noexcept;
    constexpr month_weekday_last
      operator/(const month& m, const weekday_last& wdl) noexcept;
    constexpr month_weekday_last
      operator/(int m, const weekday_last& wdl) noexcept;
    constexpr month_weekday_last
      operator/(const weekday_last& wdl, const month& m) noexcept;
    constexpr month_weekday_last
      operator/(const weekday_last& wdl, int m) noexcept;
    constexpr year_month_day
      operator/(const year_month& ym, const day& d) noexcept;
    constexpr year_month_day
      operator/(const year_month& ym, int d) noexcept;
    constexpr year_month_day
      operator/(const year& y, const month_day& md) noexcept;
    constexpr year_month_day
      operator/(int y, const month_day& md) noexcept;
    constexpr year_month_day
      operator/(const month_day& md, const year& y) noexcept;
    constexpr year_month_day
      operator/(const month_day& md, int y) noexcept;
    constexpr year_month_day_last
      operator/(const year_month& ym, last_spec) noexcept;
    constexpr year_month_day_last
      operator/(const year& y, const month_day_last& mdl) noexcept;
    constexpr year_month_day_last
      operator/(int y, const month_day_last& mdl) noexcept;
    constexpr year_month_day_last
      operator/(const month_day_last& mdl, const year& y) noexcept;
    constexpr year_month_day_last
      operator/(const month_day_last& mdl, int y) noexcept;
    constexpr year_month_weekday
      operator/(const year_month& ym, const weekday_indexed& wdi) noexcept;
    constexpr year_month_weekday
      operator/(const year& y, const month_weekday& mwd) noexcept;
    constexpr year_month_weekday
      operator/(int y, const month_weekday& mwd) noexcept;
    constexpr year_month_weekday
      operator/(const month_weekday& mwd, const year& y) noexcept;
    constexpr year_month_weekday
      operator/(const month_weekday& mwd, int y) noexcept;
    constexpr year_month_weekday_last
      operator/(const year_month& ym, const weekday_last& wdl) noexcept;
    constexpr year_month_weekday_last
      operator/(const year& y, const month_weekday_last& mwdl) noexcept;
    constexpr year_month_weekday_last
      operator/(int y, const month_weekday_last& mwdl) noexcept;
    constexpr year_month_weekday_last
      operator/(const month_weekday_last& mwdl, const year& y) noexcept;
    constexpr year_month_weekday_last
      operator/(const month_weekday_last& mwdl, int y) noexcept;
    // class template hh_mm_ss
    template<class Duration> class hh_mm_ss;
    template<class CharT, class Traits, class Duration>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const hh_mm_ss<Duration>& hms);
    // 12/24 시간 함수
    constexpr bool is_am(const hours& h) noexcept;
    constexpr bool is_pm(const hours& h) noexcept;
    constexpr hours make12(const hours& h) noexcept;
    constexpr hours make24(const hours& h, bool is_pm) noexcept;
    // time zone database
    struct tzdb;
    class tzdb_list;
    // 타임존 데이터베이스 접근
    const tzdb& get_tzdb();
    tzdb_list& get_tzdb_list();
    const time_zone* locate_zone(string_view tz_name);
    const time_zone* current_zone();
    // 원격 시간대 데이터베이스 지원
    const tzdb& reload_tzdb();
    string remote_version();
    // exception classes
    class nonexistent_local_time;
    class ambiguous_local_time;
    // information classes
    struct sys_info;
    template<class CharT, class Traits>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const sys_info& si);
    struct local_info;
    template<class CharT, class Traits>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os, const local_info& li);
    // class time_zone
    enum class choose {earliest, latest};
    class time_zone;
    bool operator==(const time_zone& x, const time_zone& y) noexcept;
    strong_ordering operator<=>(const time_zone& x, const time_zone& y) noexcept;
    // 클래스 템플릿 zoned_traits
    template<class T> struct zoned_traits;
    // 클래스 템플릿 zoned_time
    template<class Duration, class TimeZonePtr = const time_zone*> class zoned_time;
    using zoned_seconds = zoned_time<seconds>;
    template<class Duration1, class Duration2, class TimeZonePtr>
      bool operator==(const zoned_time<Duration1, TimeZonePtr>& x,
                      const zoned_time<Duration2, TimeZonePtr>& y);
    template<class CharT, class Traits, class Duration, class TimeZonePtr>
      basic_ostream<CharT, Traits>&
        operator<<(basic_ostream<CharT, Traits>& os,
                   const zoned_time<Duration, TimeZonePtr>& t);
    // 윤초 지원
    class leap_second;
    bool operator==(const leap_second& x, const leap_second& y);
    strong_ordering operator<=>(const leap_second& x, const leap_second& y);
    template<class Duration>
      constexpr bool operator==(const leap_second& x, const sys_time<Duration>& y);
    template<class Duration>
      constexpr bool operator< (const leap_second& x, const sys_time<Duration>& y);
    template<class Duration>
      constexpr bool operator< (const sys_time<Duration>& x, const leap_second& y);
    template<class Duration>
      constexpr bool operator> (const leap_second& x, const sys_time<Duration>& y);
    template<class Duration>
      constexpr bool operator> (const sys_time<Duration>& x, const leap_second& y);
    template<class Duration>
      constexpr bool operator<=(const leap_second& x, const sys_time<Duration>& y);
    template<class Duration>
      constexpr bool operator<=(const sys_time<Duration>& x, const leap_second& y);
    template<class Duration>
      constexpr bool operator>=(const leap_second& x, const sys_time<Duration>& y);
    template<class Duration>
      constexpr bool operator>=(const sys_time<Duration>& x, const leap_second& y);
    template<class Duration>
      requires three_way_comparable_with<sys_seconds, sys_time<Duration>>
      constexpr auto operator<=>(const leap_second& x, const sys_time<Duration>& y);
    // class time_zone_link
    class time_zone_link;
    bool operator==(const time_zone_link& x, const time_zone_link& y);
    strong_ordering operator<=>(const time_zone_link& x, const time_zone_link& y);
    // 포맷팅
    template<class Duration> struct /*local-time-format-t*/;    // 설명 전용
    template<class Duration>
      /*local-time-format-t*/<Duration>
        local_time_format(local_time<Duration> time, const string* abbrev = nullptr,
                          const seconds* offset_sec = nullptr);
  }
  template<class Rep, class Period, class CharT>
    struct formatter<chrono::duration<Rep, Period>, CharT>;
  template<class Duration, class CharT>
    struct formatter<chrono::sys_time<Duration>, CharT>;
  template<class Duration, class CharT>
    struct formatter<chrono::utc_time<Duration>, CharT>;
  template<class Duration, class CharT>
    struct formatter<chrono::tai_time<Duration>, CharT>;
  template<class Duration, class CharT>
    struct formatter<chrono::gps_time<Duration>, CharT>;
  template<class Duration, class CharT>
    struct formatter<chrono::file_time<Duration>, CharT>;
  template<class Duration, class CharT>
    struct formatter<chrono::local_time<Duration>, CharT>;
  template<class Duration, class CharT>
    struct formatter<chrono::/*local-time-format-t*/<Duration>, CharT>;
  template<class CharT> struct formatter<chrono::day, CharT>;
  template<class CharT> struct formatter<chrono::month, CharT>;
  template<class CharT> struct formatter<chrono::year, CharT>;
  template<class CharT> struct formatter<chrono::weekday, CharT>;
  template<class CharT> struct formatter<chrono::weekday_indexed, CharT>;
  template<class CharT> struct formatter<chrono::weekday_last, CharT>;
  template<class CharT> struct formatter<chrono::month_day, CharT>;
  template<class CharT> struct formatter<chrono::month_day_last, CharT>;
  template<class CharT> struct formatter<chrono::month_weekday, CharT>;
  template<class CharT> struct formatter<chrono::month_weekday_last, CharT>;
  template<class CharT> struct formatter<chrono::year_month, CharT>;
  template<class CharT> struct formatter<chrono::year_month_day, CharT>;
  template<class CharT> struct formatter<chrono::year_month_day_last, CharT>;
  template<class CharT> struct formatter<chrono::year_month_weekday, CharT>;
  template<class CharT> struct formatter<chrono::year_month_weekday_last, CharT>;
  template<class Rep, class Period, class CharT>
    struct formatter<chrono::hh_mm_ss<duration<Rep, Period>>, CharT>;
  template<class CharT> struct formatter<chrono::sys_info, CharT>;
  template<class CharT> struct formatter<chrono::local_info, CharT>;
  template<class Duration, class TimeZonePtr, class CharT>
    struct formatter<chrono::zoned_time<Duration, TimeZonePtr>, CharT>;
  namespace chrono {
    // 파싱
    template<class CharT, class Parsable>
      /* 미지정 */
        parse(const CharT* fmt, Parsable& tp);
    template<class CharT, class Traits, class Alloc, class Parsable>
      /* 미지정 */
        parse(const basic_string<CharT, Traits, Alloc>& format, Parsable& tp);
    template<class CharT, class traits, class Alloc, class Parsable>
      /* 미지정 */
        parse(const CharT* fmt, Parsable& tp,
              basic_string<CharT, traits, Alloc>& abbrev);
    template<class CharT, class Traits, class Alloc, class Parsable>
      /* 지정되지 않음 */
        parse(const basic_string<CharT, Traits, Alloc>& format, Parsable& tp,
              basic_string<CharT, Traits, Alloc>& abbrev);
    template<class CharT, class Parsable>
      /* 지정되지 않음 */
        parse(const CharT* fmt, Parsable& tp, minutes& offset);
    template<class CharT, class Traits, class Alloc, class Parsable>
      /* 지정되지 않음 */
        parse(const basic_string<CharT, Traits, Alloc>& format, Parsable& tp,
              minutes& offset);
    template<class CharT, class traits, class Alloc, class Parsable>
      /* 지정되지 않음 */
        parse(const CharT* fmt, Parsable& tp,
              basic_string<CharT, traits, Alloc>& abbrev, minutes& offset);
    template<class CharT, class Traits, class Alloc, class Parsable>
      /* 미지정 */
        parse(const basic_string<CharT, Traits, Alloc>& format, Parsable& tp,
              basic_string<CharT, Traits, Alloc>& abbrev, minutes& offset);
    // 달력 관련 상수
    inline constexpr last_spec last{};
    inline constexpr weekday Sunday{0};
    inline constexpr weekday Monday{1};
    inline constexpr weekday Tuesday{2};
    inline constexpr weekday Wednesday{3};
    inline constexpr weekday Thursday{4};
    inline constexpr weekday Friday{5};
    inline constexpr weekday Saturday{6};
    inline constexpr month January{1};
    inline constexpr month February{2};
    inline constexpr month March{3};
    inline constexpr month April{4};
    inline constexpr month May{5};
    inline constexpr month June{6};
    inline constexpr month July{7};
    inline constexpr month August{8};
    inline constexpr month September{9};
    inline constexpr month October{10};
    inline constexpr month November{11};
    inline constexpr month December{12};
  }
  inline namespace literals {
  inline namespace chrono_literals {
    // duration 리터럴 접미사
    constexpr chrono::시간                    operator""h(unsigned long long);
    constexpr chrono::duration</* 미지정 */,
                               ratio<3600, 1>> operator""h(long double);
    constexpr chrono::분                operator""min(unsigned long long);
    constexpr chrono::duration</* 미지정 */,
                               ratio<60, 1>> operator""min(long double);
    constexpr chrono::초                     operator""s(unsigned long long);
    constexpr chrono::duration</* 미지정 */> operator""s(long double);
    constexpr chrono::밀리초                       operator""ms(unsigned long long);
    constexpr chrono::duration</* 지정되지 않음 */, milli> operator""ms(long double);
    constexpr chrono::마이크로초                       operator""us(unsigned long long);
    constexpr chrono::duration</* 미지정 */, micro> operator""us(long double);
    constexpr chrono::나노초                       operator""ns(unsigned long long);
    constexpr chrono::duration</* 지정되지 않음 */, nano> operator""ns(long double);
    // non-member functions
    constexpr chrono::day  operator""d(unsigned long long d) noexcept;
    // non-member functions
    constexpr chrono::year operator""y(unsigned long long y) noexcept;
  }
  }
  namespace chrono {
    using namespace literals::chrono_literals;
  }
  // 해시 지원
  template<class T> struct hash;
  template<class Rep, class Period>
    struct hash<chrono::duration<Rep, Period>>;
  template<class Clock, class Duration>
    struct hash<chrono::time_point<Clock, Duration>>;
  template<> struct hash<chrono::day>;
  template<> struct hash<chrono::month>;
  template<> struct hash<chrono::year>;
  template<> struct hash<chrono::weekday>;
  template<> struct hash<chrono::weekday_indexed>;
  template<> struct hash<chrono::weekday_last>;
  template<> struct hash<chrono::month_day>;
  template<> struct hash<chrono::month_day_last>;
  template<> struct hash<chrono::month_weekday>;
  template<> struct hash<chrono::month_weekday_last>;
  template<> struct hash<chrono::year_month>;
  template<> struct hash<chrono::year_month_day>;
  template<> struct hash<chrono::year_month_day_last>;
  template<> struct hash<chrono::year_month_weekday>;
  template<> struct hash<chrono::year_month_weekday_last>;
  template<class Duration, class TimeZonePtr>
    struct hash<chrono::zoned_time<Duration, TimeZonePtr>>;
  template<> struct hash<chrono::leap_second>;
}

클래스 템플릿 std::chrono::duration

namespace std::chrono {
  template<class Rep, class Period = ratio<1>>
  class duration {
  public:
    using rep    = Rep;
    using period = typename Period::type;
  private:
    rep rep_;       // 설명용으로만 사용
  public:
    // 생성/복사/소멸
    constexpr duration() = default;
    template<class Rep2>
      constexpr explicit duration(const Rep2& r);
    template<class Rep2, class Period2>
      constexpr duration(const duration<Rep2, Period2>& d);
    ~duration() = default;
    duration(const duration&) = default;
    duration& operator=(const duration&) = default;
    // 관찰자
    constexpr rep count() const;
    // 연산
    constexpr common_type_t<duration> operator+() const;
    constexpr common_type_t<duration> operator-() const;
    constexpr duration& operator++();
    constexpr duration  operator++(int);
    constexpr duration& operator--();
    constexpr duration  operator--(int);
    constexpr duration& operator+=(const duration& d);
    constexpr duration& operator-=(const duration& d);
    constexpr duration& operator*=(const rep& rhs);
    constexpr duration& operator/=(const rep& rhs);
    constexpr duration& operator%=(const rep& rhs);
    constexpr duration& operator%=(const duration& rhs);
    // 특수 값
    static constexpr duration zero() noexcept;
    static constexpr duration min() noexcept;
    static constexpr duration max() noexcept;
  };
}

클래스 템플릿 std::chrono::time_point

namespace std::chrono {
  template<class Clock, class Duration = typename Clock::duration>
  class time_point {
  public:
    using clock    = Clock;
    using duration = Duration;
    using rep      = typename duration::rep;
    using period   = typename duration::period;
  private:
    duration d_;                                                // 설명용으로만 사용
  public:
    // 생성자
    constexpr time_point();                                     // epoch 값을 가짐
    constexpr explicit time_point(const duration& d);           // time_point() + d와 동일
    template<class Duration2>
      constexpr time_point(const time_point<clock, Duration2>& t);
    // 관찰자
    constexpr duration time_since_epoch() const;
    // 연산
    constexpr time_point& operator++();
    constexpr time_point operator++(int);
    constexpr time_point& operator--();
    constexpr time_point operator--(int);
    constexpr time_point& operator+=(const duration& d);
    constexpr time_point& operator-=(const duration& d);
    // 특수 값
    static constexpr time_point min() noexcept;
    static constexpr time_point max() noexcept;
  };
}

클래스 템플릿 std::common_type 의 std::chrono::duration 전문화

namespace std {
  template<class Rep1, class Period1, class Rep2, class Period2>
    struct common_type<chrono::duration<Rep1, Period1>,
                       chrono::duration<Rep2, Period2>> {
      using type = chrono::duration<common_type_t<Rep1, Rep2>, /* 설명 참조 */>;
    };
}

클래스 템플릿 std::common_type 의 std::chrono::time_point 특수화

namespace std {
  template<class Clock, class Duration1, class Duration2>
    struct common_type<chrono::time_point<Clock, Duration1>,
                       chrono::time_point<Clock, Duration2>> {
      using type = chrono::time_point<Clock, common_type_t<Duration1, Duration2>>;
    };
}

클래스 템플릿 std::chrono::treat_as_floating_point

template<class Rep> struct treat_as_floating_point : is_floating_point<Rep> { };

클래스 템플릿 std::chrono::duration_values

namespace std::chrono {
  template<class Rep>
    struct duration_values {
    public:
      static constexpr Rep zero() noexcept;
      static constexpr Rep min() noexcept;
      static constexpr Rep max() noexcept;
    };
}

클래스 std::chrono::system_clock

namespace std::chrono {
  class system_clock {
  public:
    using rep        = /* 설명 참조 */;
    using period     = ratio</* 지정되지 않음 */, /* 지정되지 않음 */>;
    using duration   = chrono::duration<rep, period>;
    using time_point = chrono::time_point<system_clock>;
    static constexpr bool is_steady = /* 지정되지 않음 */;
    static time_point now() noexcept;
    // C 타입 time_t와의 상호 변환
    static time_t      to_time_t  (const time_point& t) noexcept;
    static time_point  from_time_t(time_t t) noexcept;
  };
}

클래스 std:: chrono :: utc_clock

namespace std::chrono {
  class utc_clock {
  public:
    using rep                       = /* 부호 있는 산술 타입 */;
    using period                    = ratio</* 지정되지 않음 */, /* 지정되지 않음 */>;
    using duration                  = chrono::duration<rep, period>;
    using time_point                = chrono::time_point<utc_clock>;
    static constexpr bool is_steady = /* 지정되지 않음 */;
    static time_point now();
    template<class Duration>
      static sys_time<common_type_t<Duration, seconds>>
        to_sys(const utc_time<Duration>& t);
    template<class Duration>
      static utc_time<common_type_t<Duration, seconds>>
        from_sys(const sys_time<Duration>& t);
  };
}

클래스 std:: chrono :: tai_clock

namespace std::chrono {
  class tai_clock {
  public:
    using rep                       = /* 부호 있는 산술 타입 */;
    using period                    = ratio</* 지정되지 않음 */, /* 지정되지 않음 */>;
    using duration                  = chrono::duration<rep, period>;
    using time_point                = chrono::time_point<tai_clock>;
    static constexpr bool is_steady = /* 지정되지 않음 */;
    static time_point now();
    template<class Duration>
      static sys_time<common_type_t<Duration, seconds>>
        to_sys(const tai_time<Duration>& t);
    template<class Duration>
      static tai_time<common_type_t<Duration, seconds>>
        from_sys(const sys_time<Duration>& t);
  };
}

클래스 std:: chrono :: gps_clock

namespace std::chrono {
  class gps_clock {
  public:
    using rep                       = /* 부호 있는 산술 타입 */;
    using period                    = ratio</* 지정되지 않음 */, /* 지정되지 않음 */>;
    using duration                  = chrono::duration<rep, period>;
    using time_point                = chrono::time_point<gps_clock>;
    static constexpr bool is_steady = /* 지정되지 않음 */;
    static time_point now();
    template<class Duration>
      static sys_time<common_type_t<Duration, seconds>>
        to_sys(const gps_time<Duration>& t);
    template<class Duration>
      static gps_time<common_type_t<Duration, seconds>>
        from_sys(const sys_time<Duration>& t);
  };
}

클래스 std::chrono::steady_clock

namespace std::chrono {
  class steady_clock {
  public:
    using rep        = /* 지정되지 않음 */;
    using period     = ratio</* 지정되지 않음 */, /* 지정되지 않음 */>;
    using duration   = chrono::duration<rep, period>;
    using time_point = chrono::time_point</* 지정되지 않음 */, duration>;
    static constexpr bool is_steady = true;
    static time_point now() noexcept;
  };
}

클래스 std::chrono::high_resolution_clock

namespace std::chrono {
  class high_resolution_clock {
  public:
    using rep        = /* 지정되지 않음 */;
    using period     = ratio</* 지정되지 않음 */, /* 지정되지 않음 */>;
    using duration   = chrono::duration<rep, period>;
    using time_point = chrono::time_point</* 지정되지 않음 */, duration>;
    static constexpr bool is_steady = /* 지정되지 않음 */;
    static time_point now() noexcept;
  };
}

클래스 템플릿 std:: chrono :: clock_time_conversion

namespace std::chrono {
  template<class DestClock, class SourceClock>
  struct clock_time_conversion {};
  template<class Clock>
  struct clock_time_conversion<Clock, Clock> {
    template<class Duration>
      time_point<Clock, Duration>
        operator()(const time_point<Clock, Duration>& t) const;
  };
  template<>
  struct clock_time_conversion<system_clock, system_clock> {
    template<class Duration>
      sys_time<Duration>
        operator()(const sys_time<Duration>& t) const;
  };
  template<>
  struct clock_time_conversion<utc_clock, utc_clock> {
    template<class Duration>
      utc_time<Duration>
        operator()(const utc_time<Duration>& t) const;
  };
  template<>
  struct clock_time_conversion<utc_clock, system_clock> {
    template<class Duration>
      utc_time<common_type_t<Duration, seconds>>
        operator()(const sys_time<Duration>& t) const;
  };
  template<>
  struct clock_time_conversion<system_clock, utc_clock> {
    template<class Duration>
      sys_time<common_type_t<Duration, seconds>>
        operator()(const utc_time<Duration>& t) const;
  };
  template<class SourceClock>
  struct clock_time_conversion<system_clock, SourceClock> {
    template<class Duration>
      auto operator()(const time_point<SourceClock, Duration>& t) const
        -> decltype(SourceClock::to_sys(t));
  };
  template<class DestClock>
  struct clock_time_conversion<DestClock, system_clock> {
    template<class Duration>
      auto operator()(const sys_time<Duration>& t) const
        -> decltype(DestClock::from_sys(t));
  };
  template<class SourceClock>
  struct clock_time_conversion<utc_clock, SourceClock> {
    template<class Duration>
      auto operator()(const time_point<SourceClock, Duration>& t) const
        -> decltype(SourceClock::to_utc(t));
  };
  template<class DestClock>
  struct clock_time_conversion<DestClock, utc_clock> {
    template<class Duration>
      auto operator()(const utc_time<Duration>& t) const
        -> decltype(DestClock::from_utc(t));
  };
}

클래스 std:: chrono :: last_spec

namespace std::chrono {
  struct last_spec {
    explicit last_spec() = default;
  };
}

클래스 std:: chrono :: day

namespace std::chrono {
  class day {
    unsigned char d_;           // 설명 전용
  public:
    day() = default;
    constexpr explicit day(unsigned d) noexcept;
    constexpr day& operator++()    noexcept;
    constexpr day  operator++(int) noexcept;
    constexpr day& operator--()    noexcept;
    constexpr day  operator--(int) noexcept;
    constexpr day& operator+=(const days& d) noexcept;
    constexpr day& operator-=(const days& d) noexcept;
    constexpr explicit operator unsigned() const noexcept;
    constexpr bool ok() const noexcept;
  };
}

클래스 std:: chrono :: month

namespace std::chrono {
  class month {
    unsigned char m_;           // 설명 전용
  public:
    month() = default;
    constexpr explicit month(unsigned m) noexcept;
    constexpr month& operator++()    noexcept;
    constexpr month  operator++(int) noexcept;
    constexpr month& operator--()    noexcept;
    constexpr month  operator--(int) noexcept;
    constexpr month& operator+=(const months& m) noexcept;
    constexpr month& operator-=(const months& m) noexcept;
    constexpr explicit operator unsigned() const noexcept;
    constexpr bool ok() const noexcept;
  };
}

클래스 std:: chrono :: year

namespace std::chrono {
  class year {
    short y_;                   // 설명용으로만 사용
  public:
    year() = default;
    constexpr explicit year(int y) noexcept;
    constexpr year& operator++()    noexcept;
    constexpr year  operator++(int) noexcept;
    constexpr year& operator--()    noexcept;
    constexpr year  operator--(int) noexcept;
    constexpr year& operator+=(const years& y) noexcept;
    constexpr year& operator-=(const years& y) noexcept;
    constexpr year operator+() const noexcept;
    constexpr year operator-() const noexcept;
    constexpr bool is_leap() const noexcept;
    constexpr explicit operator int() const noexcept;
    constexpr bool ok() const noexcept;
    static constexpr year min() noexcept;
    static constexpr year max() noexcept;
  };
}

클래스 std:: chrono :: weekday

namespace std::chrono {
  class weekday {
    unsigned char wd_;          // 설명용 전용
  public:
    weekday() = default;
    constexpr explicit weekday(unsigned wd) noexcept;
    constexpr weekday(const sys_days& dp) noexcept;
    constexpr explicit weekday(const local_days& dp) noexcept;
    constexpr weekday& operator++()    noexcept;
    constexpr weekday  operator++(int) noexcept;
    constexpr weekday& operator--()    noexcept;
    constexpr weekday  operator--(int) noexcept;
    constexpr weekday& operator+=(const days& d) noexcept;
    constexpr weekday& operator-=(const days& d) noexcept;
    constexpr unsigned c_encoding() const noexcept;
    constexpr unsigned iso_encoding() const noexcept;
    constexpr bool ok() const noexcept;
    constexpr weekday_indexed operator[](unsigned index) const noexcept;
    constexpr weekday_last    operator[](last_spec) const noexcept;
  };
}

클래스 std:: chrono :: weekday_indexed

namespace std::chrono {
  class weekday_indexed {
    chrono::weekday  wd_;       // 설명용 전용
    unsigned char    index_;    // 설명용 전용
  public:
    weekday_indexed() = default;
    constexpr weekday_indexed(const chrono::weekday& wd, unsigned index) noexcept;
    constexpr chrono::weekday weekday() const noexcept;
    constexpr unsigned        index()   const noexcept;
    constexpr bool ok() const noexcept;
  };
}

클래스 std:: chrono :: weekday_last

namespace std::chrono {
  class weekday_last {
    chrono::weekday wd_;                // 설명용
    public:
    constexpr explicit weekday_last(const chrono::weekday& wd) noexcept;
    constexpr chrono::weekday weekday() const noexcept;
    constexpr bool ok() const noexcept;
  };
}

클래스 std:: chrono :: month_day

namespace std::chrono {
  class month_day {
    chrono::month m_;           // 설명 전용
    chrono::day   d_;           // 설명 전용
  public:
    month_day() = default;
    constexpr month_day(const chrono::month& m, const chrono::day& d) noexcept;
    constexpr chrono::month month() const noexcept;
    constexpr chrono::day   day()   const noexcept;
    constexpr bool ok() const noexcept;
  };
}

클래스 std:: chrono :: month_day_last

namespace std::chrono {
  class month_day_last {
    chrono::month m_;                   // 설명용 전용
  public:
    constexpr explicit month_day_last(const chrono::month& m) noexcept;
    constexpr chrono::month month() const noexcept;
    constexpr bool ok() const noexcept;
  };
}

클래스 std:: chrono :: month_weekday

namespace std::chrono {
  class month_weekday {
    chrono::month           m_;         // 설명 전용
    chrono::weekday_indexed wdi_;       // 설명 전용
  public:
    constexpr month_weekday(const chrono::month& m,
                            const chrono::weekday_indexed& wdi) noexcept;
    constexpr chrono::month           month()           const noexcept;
    constexpr chrono::weekday_indexed weekday_indexed() const noexcept;
    constexpr bool ok() const noexcept;
  };
}

클래스 std:: chrono :: month_weekday_last

namespace std::chrono {
  class month_weekday_last {
    chrono::month        m_;    // 설명용 전용
    chrono::weekday_last wdl_;  // 설명용 전용
  public:
    constexpr month_weekday_last(const chrono::month& m,
                                 const chrono::weekday_last& wdl) noexcept;
    constexpr chrono::month        month()        const noexcept;
    constexpr chrono::weekday_last weekday_last() const noexcept;
    constexpr bool ok() const noexcept;
  };
}

클래스 std:: chrono :: year_month

namespace std::chrono {
  class year_month {
    chrono::year  y_;           // 설명용 전용
    chrono::month m_;           // 설명용 전용
  public:
    year_month() = default;
    constexpr year_month(const chrono::year& y, const chrono::month& m) noexcept;
    constexpr chrono::year  year()  const noexcept;
    constexpr chrono::month month() const noexcept;
    constexpr year_month& operator+=(const months& dm) noexcept;
    constexpr year_month& operator-=(const months& dm) noexcept;
    constexpr year_month& operator+=(const years& dy)  noexcept;
    constexpr year_month& operator-=(const years& dy)  noexcept;
    constexpr bool ok() const noexcept;
  };
}

클래스 std:: chrono :: year_month_day

namespace std::chrono {
  class year_month_day {
    chrono::year  y_;           // 설명용 전용
    chrono::month m_;           // 설명용 전용
    chrono::day   d_;           // 설명용 전용
  public:
    year_month_day() = default;
    constexpr year_month_day(const chrono::year& y, const chrono::month& m,
                             const chrono::day& d) noexcept;
    constexpr year_month_day(const year_month_day_last& ymdl) noexcept;
    constexpr year_month_day(const sys_days& dp) noexcept;
    constexpr explicit year_month_day(const local_days& dp) noexcept;
    constexpr year_month_day& operator+=(const months& m) noexcept;
    constexpr year_month_day& operator-=(const months& m) noexcept;
    constexpr year_month_day& operator+=(const years& y)  noexcept;
    constexpr year_month_day& operator-=(const years& y)  noexcept;
    constexpr chrono::year  year()  const noexcept;
    constexpr chrono::month month() const noexcept;
    constexpr chrono::day   day()   const noexcept;
    constexpr          operator sys_days()   const noexcept;
    constexpr explicit operator local_days() const noexcept;
    constexpr bool ok() const noexcept;
  };
}

클래스 std:: chrono :: year_month_day_last

namespace std::chrono {
  class year_month_day_last {
    chrono::year           y_;          // 설명용 전용
    chrono::month_day_last mdl_;        // 설명용 전용
  public:
    constexpr year_month_day_last(const chrono::year& y,
                                  const chrono::month_day_last& mdl) noexcept;
    constexpr year_month_day_last& operator+=(const months& m) noexcept;
    constexpr year_month_day_last& operator-=(const months& m) noexcept;
    constexpr year_month_day_last& operator+=(const years& y)  noexcept;
    constexpr year_month_day_last& operator-=(const years& y)  noexcept;
    constexpr chrono::year           year()           const noexcept;
    constexpr chrono::month          month()          const noexcept;
    constexpr chrono::month_day_last month_day_last() const noexcept;
    constexpr chrono::day            day()            const noexcept;
    constexpr          operator sys_days()   const noexcept;
    constexpr explicit operator local_days() const noexcept;
    constexpr bool ok() const noexcept;
  };
}

클래스 std:: chrono :: year_month_weekday

namespace std::chrono {
  class year_month_weekday {
    chrono::year            y_;         // 설명용 전용
    chrono::month           m_;         // 설명용 전용
    chrono::weekday_indexed wdi_;       // 설명용 전용
  public:
    year_month_weekday() = default;
    constexpr year_month_weekday(const chrono::year& y, const chrono::month& m,
                                 const chrono::weekday_indexed& wdi) noexcept;
    constexpr year_month_weekday(const sys_days& dp) noexcept;
    constexpr explicit year_month_weekday(const local_days& dp) noexcept;
    constexpr year_month_weekday& operator+=(const months& m) noexcept;
    constexpr year_month_weekday& operator-=(const months& m) noexcept;
    constexpr year_month_weekday& operator+=(const years& y)  noexcept;
    constexpr year_month_weekday& operator-=(const years& y)  noexcept;
    constexpr chrono::year            year()            const noexcept;
    constexpr chrono::month           month()           const noexcept;
    constexpr chrono::weekday         weekday()         const noexcept;
    constexpr unsigned                index()           const noexcept;
    constexpr chrono::weekday_indexed weekday_indexed() const noexcept;
    constexpr          operator sys_days()   const noexcept;
    constexpr explicit operator local_days() const noexcept;
    constexpr bool ok() const noexcept;
  };
}

클래스 std:: chrono :: year_month_weekday_last

namespace std::chrono {
  class year_month_weekday_last {
    chrono::year         y_;    // 설명용 전용
    chrono::month        m_;    // 설명용 전용
    chrono::weekday_last wdl_;  // 설명용 전용
  public:
    constexpr year_month_weekday_last(const chrono::year& y, const chrono::month& m,
                                      const chrono::weekday_last& wdl) noexcept;
    constexpr year_month_weekday_last& operator+=(const months& m) noexcept;
    constexpr year_month_weekday_last& operator-=(const months& m) noexcept;
    constexpr year_month_weekday_last& operator+=(const years& y)  noexcept;
    constexpr year_month_weekday_last& operator-=(const years& y)  noexcept;
    constexpr chrono::year         year()         const noexcept;
    constexpr chrono::month        month()        const noexcept;
    constexpr chrono::weekday      weekday()      const noexcept;
    constexpr chrono::weekday_last weekday_last() const noexcept;
    constexpr          operator sys_days()   const noexcept;
    constexpr explicit operator local_days() const noexcept;
    constexpr bool ok() const noexcept;
  };
}

클래스 템플릿 std::chrono::hh_mm_ss

namespace std::chrono {
  template<class Duration> class hh_mm_ss {
  public:
    static constexpr unsigned fractional_width = /* 설명 참조 */;
    using precision                            = /* 설명 참조 */;
    constexpr hh_mm_ss() noexcept : hh_mm_ss{Duration::zero()} {}
    constexpr explicit hh_mm_ss(Duration d);
    constexpr bool is_negative() const noexcept;
    constexpr chrono::hours hours() const noexcept;
    constexpr chrono::minutes minutes() const noexcept;
    constexpr chrono::seconds seconds() const noexcept;
    constexpr precision subseconds() const noexcept;
    constexpr explicit operator precision() const noexcept;
    constexpr precision to_duration() const noexcept;
  private:
    bool            is_neg;     // 설명 전용
    chrono::hours   h;          // 설명 전용
    chrono::minutes m;          // 설명 전용
    chrono::seconds s;          // 설명 전용
    precision       ss;         // 설명 전용
  };
}

클래스 std:: chrono :: tzdb

namespace std::chrono {
  struct tzdb {
    string                 version;
    vector<time_zone>      zones;
    vector<time_zone_link> links;
    vector<leap_second>    leap_seconds;
    const time_zone* locate_zone(string_view tz_name) const;
    const time_zone* current_zone() const;
  };
}

클래스 std:: chrono :: tzdb_list

namespace std::chrono {
  class tzdb_list {
  public:
    tzdb_list(const tzdb_list&) = delete;
    tzdb_list& operator=(const tzdb_list&) = delete;
    // 명시되지 않은 추가 생성자들
    class const_iterator;
    const tzdb& front() const noexcept;
    const_iterator erase_after(const_iterator p);
    const_iterator begin() const noexcept;
    const_iterator end()   const noexcept;
    const_iterator cbegin() const noexcept;
    const_iterator cend()   const noexcept;
  };
}

클래스 std:: chrono :: nonexistent_local_time

namespace std::chrono {
  class nonexistent_local_time : public runtime_error {
  public:
    template<class Duration>
      nonexistent_local_time(const local_time<Duration>& tp, const local_info& i);
  };
}

클래스 std:: chrono :: ambiguous_local_time

namespace std::chrono {
  class ambiguous_local_time : public runtime_error {
  public:
    template<class Duration>
      ambiguous_local_time(const local_time<Duration>& tp, const local_info& i);
  };
}

클래스 std:: chrono :: sys_info

namespace std::chrono {
  struct sys_info {
    sys_seconds   begin;
    sys_seconds   end;
    seconds       offset;
    minutes       save;
    string        abbrev;
  };
}

클래스 std:: chrono :: local_info

namespace std::chrono {
  struct local_info {
    static constexpr int unique      = 0;
    static constexpr int nonexistent = 1;
    static constexpr int ambiguous   = 2;
    int result;
    sys_info first;
    sys_info second;
  };
}

클래스 std:: chrono :: time_zone

namespace std::chrono {
  class time_zone {
  public:
    time_zone(time_zone&&) = default;
    time_zone& operator=(time_zone&&) = default;
    // 명시되지 않은 추가 생성자들
    string_view name() const noexcept;
    template<class Duration> sys_info   get_info(const sys_time<Duration>& st)   const;
    template<class Duration> local_info get_info(const local_time<Duration>& tp) const;
    template<class Duration>
      sys_time<common_type_t<Duration, seconds>>
        to_sys(const local_time<Duration>& tp) const;
    template<class Duration>
      sys_time<common_type_t<Duration, seconds>>
        to_sys(const local_time<Duration>& tp, choose z) const;
    template<class Duration>
      local_time<common_type_t<Duration, seconds>>
        to_local(const sys_time<Duration>& tp) const;
  };
}

클래스 템플릿 std:: chrono :: zoned_traits

namespace std::chrono {
  template<class T> struct zoned_traits {};
  template<> struct zoned_traits<const time_zone*> {
    static const time_zone* default_zone();
    static const time_zone* locate_zone(string_view name);
  };
}

클래스 템플릿 std:: chrono :: zoned_time

namespace std::chrono {
  template<class Duration, class TimeZonePtr = const time_zone*>
  class zoned_time {
  public:
    using duration = common_type_t<Duration, seconds>;
  private:
    TimeZonePtr        zone_;                   // 설명 전용
    sys_time<duration> tp_;                     // 설명 전용
    using traits = zoned_traits<TimeZonePtr>;   // 설명 전용
  public:
    zoned_time();
    zoned_time(const zoned_time&) = default;
    zoned_time& operator=(const zoned_time&) = default;
    zoned_time(const sys_time<Duration>& st);
    explicit zoned_time(TimeZonePtr z);
    explicit zoned_time(string_view name);
    template<class Duration2>
      zoned_time(const zoned_time<Duration2, TimeZonePtr>& zt);
    zoned_time(TimeZonePtr z,    const sys_time<Duration>& st);
    zoned_time(string_view name, const sys_time<Duration>& st);
    zoned_time(TimeZonePtr z,    const local_time<Duration>& tp);
    zoned_time(string_view name, const local_time<Duration>& tp);
    zoned_time(TimeZonePtr z,    const local_time<Duration>& tp, choose c);
    zoned_time(string_view name, const local_time<Duration>& tp, choose c);
    template<class Duration2, class TimeZonePtr2>
      zoned_time(TimeZonePtr z, const zoned_time<Duration2, TimeZonePtr2>& zt);
    template<class Duration2, class TimeZonePtr2>
      zoned_time(TimeZonePtr z, const zoned_time<Duration2, TimeZonePtr2>& zt, choose);
    template<class Duration2, class TimeZonePtr2>
      zoned_time(string_view name, const zoned_time<Duration2, TimeZonePtr2>& zt);
    template<class Duration2, class TimeZonePtr2>
      zoned_time(string_view name, const zoned_time<Duration2, TimeZonePtr2>& zt, choose);
    zoned_time& operator=(const sys_time<Duration>& st);
    zoned_time& operator=(const local_time<Duration>& ut);
    operator sys_time<duration>() const;
    explicit operator local_time<duration>() const;
    TimeZonePtr          get_time_zone()  const;
    local_time<duration> get_local_time() const;
    sys_time<duration>   get_sys_time()   const;
    sys_info             get_info()       const;
  };
  zoned_time() -> zoned_time<seconds>;
  template<class Duration>
    zoned_time(sys_time<Duration>)
      -> zoned_time<common_type_t<Duration, seconds>>;
  template<class TimeZonePtrOrName>
    using /*시간대-표현*/ =        // 설명 전용
      conditional_t<is_convertible_v<TimeZonePtrOrName, string_view>,
                    const time_zone*,
                    remove_cvref_t<TimeZonePtrOrName>>;
  template<class TimeZonePtrOrName>
    zoned_time(TimeZonePtrOrName&&)
      -> zoned_time<seconds, /*시간대-표현*/<TimeZonePtrOrName>>;
  template<class TimeZonePtrOrName, class Duration>
    zoned_time(TimeZonePtrOrName&&, sys_time<Duration>)
      -> zoned_time<common_type_t<Duration, seconds>,
                    /*시간대-표현*/<TimeZonePtrOrName>>;
  template<class TimeZonePtrOrName, class Duration>
    zoned_time(TimeZonePtrOrName&&, local_time<Duration>,
               choose = choose::가장 빠른)
      -> zoned_time<common_type_t<Duration, seconds>,
                    /*시간대-표현*/<TimeZonePtrOrName>>;
  template<class Duration, class TimeZonePtrOrName, class TimeZonePtr2>
    zoned_time(TimeZonePtrOrName&&, zoned_time<Duration, TimeZonePtr2>,
               choose = choose::가장 빠른)
      -> zoned_time<common_type_t<Duration, seconds>,
                    /*시간대-표현*/<TimeZonePtrOrName>>;
}

클래스 std::chrono::leap_second

namespace std::chrono {
  class leap_second {
  public:
    leap_second(const leap_second&)            = default;
    leap_second& operator=(const leap_second&) = default;
    // 지정되지 않은 추가 생성자들
    constexpr sys_seconds date() const noexcept;
    constexpr seconds value() const noexcept;
  };
}

클래스 std::chrono::time_zone_link

namespace std::chrono {
  class time_zone_link {
  public:
    time_zone_link(time_zone_link&&)            = default;
    time_zone_link& operator=(time_zone_link&&) = default;
    // 명시되지 않은 추가 생성자들
    string_view name()   const noexcept;
    string_view target() const noexcept;
  };
}

클래스 템플릿 `local-time-format-t`

namespace std::chrono {
  template<class Duration> struct /*local-time-format-t*/ {       // 설명용 전용
    local_time<Duration> time;                                    // 설명용 전용
    const string* abbrev;                                         // 설명용 전용
    const seconds* offset_sec;                                    // 설명용 전용
  };
}

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Standard library header <chrono> (C++11)

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클래스

Duration

편의 duration typedefs

시간 포인트

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시간대

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Duration

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리터럴

시놉시스

클래스 템플릿 std::chrono::duration

클래스 템플릿 std::chrono::time_point

클래스 템플릿 std::common_type 의 std::chrono::duration 전문화

클래스 템플릿 std::common_type 의 std::chrono::time_point 특수화

클래스 템플릿 std::chrono::treat_as_floating_point

클래스 템플릿 std::chrono::duration_values

클래스 std::chrono::system_clock

클래스 std:: chrono :: utc_clock

클래스 std:: chrono :: tai_clock

클래스 std:: chrono :: gps_clock

클래스 std::chrono::steady_clock

클래스 std::chrono::high_resolution_clock

클래스 템플릿 std:: chrono :: clock_time_conversion

클래스 std:: chrono :: last_spec

클래스 std:: chrono :: day

클래스 std:: chrono :: month

클래스 std:: chrono :: year

클래스 std:: chrono :: weekday

클래스 std:: chrono :: weekday_indexed

클래스 std:: chrono :: weekday_last

클래스 std:: chrono :: month_day

클래스 std:: chrono :: month_day_last

클래스 std:: chrono :: month_weekday

클래스 std:: chrono :: month_weekday_last

클래스 std:: chrono :: year_month

클래스 std:: chrono :: year_month_day

클래스 std:: chrono :: year_month_day_last

클래스 std:: chrono :: year_month_weekday

클래스 std:: chrono :: year_month_weekday_last

클래스 템플릿 std::chrono::hh_mm_ss

클래스 std:: chrono :: tzdb

클래스 std:: chrono :: tzdb_list

클래스 std:: chrono :: nonexistent_local_time

클래스 std:: chrono :: ambiguous_local_time

클래스 std:: chrono :: sys_info

클래스 std:: chrono :: local_info

클래스 std:: chrono :: time_zone

클래스 템플릿 std:: chrono :: zoned_traits

클래스 템플릿 std:: chrono :: zoned_time

클래스 std::chrono::leap_second

클래스 std::chrono::time_zone_link

클래스 템플릿 local-time-format-t

클래스 템플릿 `local-time-format-t`