xref: /llvm-project-15.0.7/libcxx/include/chrono (revision bacf751a)
1// -*- C++ -*-
2//===---------------------------- chrono ----------------------------------===//
3//
4//                     The LLVM Compiler Infrastructure
5//
6// This file is dual licensed under the MIT and the University of Illinois Open
7// Source Licenses. See LICENSE.TXT for details.
8//
9//===----------------------------------------------------------------------===//
10
11#ifndef _LIBCPP_CHRONO
12#define _LIBCPP_CHRONO
13
14/*
15    chrono synopsis
16
17namespace std
18{
19namespace chrono
20{
21
22template <class ToDuration, class Rep, class Period>
23constexpr
24ToDuration
25duration_cast(const duration<Rep, Period>& fd);
26
27template <class Rep> struct treat_as_floating_point : is_floating_point<Rep> {};
28
29template <class Rep> inline constexpr bool treat_as_floating_point_v
30    = treat_as_floating_point<Rep>::value;                       // C++17
31
32template <class Rep>
33struct duration_values
34{
35public:
36    static constexpr Rep zero();
37    static constexpr Rep max();
38    static constexpr Rep min();
39};
40
41// duration
42
43template <class Rep, class Period = ratio<1>>
44class duration
45{
46    static_assert(!__is_duration<Rep>::value, "A duration representation can not be a duration");
47    static_assert(__is_ratio<Period>::value, "Second template parameter of duration must be a std::ratio");
48    static_assert(Period::num > 0, "duration period must be positive");
49public:
50    typedef Rep rep;
51    typedef typename _Period::type period;
52
53    constexpr duration() = default;
54    template <class Rep2>
55        constexpr explicit duration(const Rep2& r,
56            typename enable_if
57            <
58               is_convertible<Rep2, rep>::value &&
59               (treat_as_floating_point<rep>::value ||
60               !treat_as_floating_point<rep>::value && !treat_as_floating_point<Rep2>::value)
61            >::type* = 0);
62
63    // conversions
64    template <class Rep2, class Period2>
65        constexpr duration(const duration<Rep2, Period2>& d,
66            typename enable_if
67            <
68                treat_as_floating_point<rep>::value ||
69                ratio_divide<Period2, period>::type::den == 1
70            >::type* = 0);
71
72    // observer
73
74    constexpr rep count() const;
75
76    // arithmetic
77
78    constexpr common_type<duration>::type  operator+() const;
79    constexpr common_type<duration>::type  operator-() const;
80    constexpr duration& operator++();    // constexpr in C++17
81    constexpr duration  operator++(int); // constexpr in C++17
82    constexpr duration& operator--();    // constexpr in C++17
83    constexpr duration  operator--(int); // constexpr in C++17
84
85    constexpr duration& operator+=(const duration& d);  // constexpr in C++17
86    constexpr duration& operator-=(const duration& d);  // constexpr in C++17
87
88    duration& operator*=(const rep& rhs);       // constexpr in C++17
89    duration& operator/=(const rep& rhs);       // constexpr in C++17
90    duration& operator%=(const rep& rhs);       // constexpr in C++17
91    duration& operator%=(const duration& rhs);  // constexpr in C++17
92
93    // special values
94
95    static constexpr duration zero();
96    static constexpr duration min();
97    static constexpr duration max();
98};
99
100typedef duration<long long,         nano> nanoseconds;
101typedef duration<long long,        micro> microseconds;
102typedef duration<long long,        milli> milliseconds;
103typedef duration<long long              > seconds;
104typedef duration<     long, ratio<  60> > minutes;
105typedef duration<     long, ratio<3600> > hours;
106
107template <class Clock, class Duration = typename Clock::duration>
108class time_point
109{
110public:
111    typedef Clock                     clock;
112    typedef Duration                  duration;
113    typedef typename duration::rep    rep;
114    typedef typename duration::period period;
115private:
116    duration d_;  // exposition only
117
118public:
119    time_point();  // has value "epoch" // constexpr in C++14
120    explicit time_point(const duration& d);  // same as time_point() + d // constexpr in C++14
121
122    // conversions
123    template <class Duration2>
124       time_point(const time_point<clock, Duration2>& t); // constexpr in C++14
125
126    // observer
127
128    duration time_since_epoch() const; // constexpr in C++14
129
130    // arithmetic
131
132    time_point& operator+=(const duration& d); // constexpr in C++17
133    time_point& operator-=(const duration& d); // constexpr in C++17
134
135    // special values
136
137    static constexpr time_point min();
138    static constexpr time_point max();
139};
140
141} // chrono
142
143// common_type traits
144template <class Rep1, class Period1, class Rep2, class Period2>
145  struct common_type<chrono::duration<Rep1, Period1>, chrono::duration<Rep2, Period2>>;
146
147template <class Clock, class Duration1, class Duration2>
148  struct common_type<chrono::time_point<Clock, Duration1>, chrono::time_point<Clock, Duration2>>;
149
150namespace chrono {
151
152
153template<class T> struct is_clock;  // C++20
154template<class T> inline constexpr bool is_clock_v = is_clock<T>::value;   // C++20
155
156
157// duration arithmetic
158template <class Rep1, class Period1, class Rep2, class Period2>
159  constexpr
160  typename common_type<duration<Rep1, Period1>, duration<Rep2, Period2>>::type
161  operator+(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
162template <class Rep1, class Period1, class Rep2, class Period2>
163  constexpr
164  typename common_type<duration<Rep1, Period1>, duration<Rep2, Period2>>::type
165  operator-(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
166template <class Rep1, class Period, class Rep2>
167  constexpr
168  duration<typename common_type<Rep1, Rep2>::type, Period>
169  operator*(const duration<Rep1, Period>& d, const Rep2& s);
170template <class Rep1, class Period, class Rep2>
171  constexpr
172  duration<typename common_type<Rep1, Rep2>::type, Period>
173  operator*(const Rep1& s, const duration<Rep2, Period>& d);
174template <class Rep1, class Period, class Rep2>
175  constexpr
176  duration<typename common_type<Rep1, Rep2>::type, Period>
177  operator/(const duration<Rep1, Period>& d, const Rep2& s);
178template <class Rep1, class Period1, class Rep2, class Period2>
179  constexpr
180  typename common_type<Rep1, Rep2>::type
181  operator/(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
182
183// duration comparisons
184template <class Rep1, class Period1, class Rep2, class Period2>
185   constexpr
186   bool operator==(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
187template <class Rep1, class Period1, class Rep2, class Period2>
188   constexpr
189   bool operator!=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
190template <class Rep1, class Period1, class Rep2, class Period2>
191   constexpr
192   bool operator< (const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
193template <class Rep1, class Period1, class Rep2, class Period2>
194   constexpr
195   bool operator<=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
196template <class Rep1, class Period1, class Rep2, class Period2>
197   constexpr
198   bool operator> (const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
199template <class Rep1, class Period1, class Rep2, class Period2>
200   constexpr
201   bool operator>=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
202
203// duration_cast
204template <class ToDuration, class Rep, class Period>
205  ToDuration duration_cast(const duration<Rep, Period>& d);
206
207template <class ToDuration, class Rep, class Period>
208    constexpr ToDuration floor(const duration<Rep, Period>& d);    // C++17
209template <class ToDuration, class Rep, class Period>
210    constexpr ToDuration ceil(const duration<Rep, Period>& d);     // C++17
211template <class ToDuration, class Rep, class Period>
212    constexpr ToDuration round(const duration<Rep, Period>& d);    // C++17
213
214// duration I/O is elsewhere
215
216// time_point arithmetic (all constexpr in C++14)
217template <class Clock, class Duration1, class Rep2, class Period2>
218  time_point<Clock, typename common_type<Duration1, duration<Rep2, Period2>>::type>
219  operator+(const time_point<Clock, Duration1>& lhs, const duration<Rep2, Period2>& rhs);
220template <class Rep1, class Period1, class Clock, class Duration2>
221  time_point<Clock, typename common_type<duration<Rep1, Period1>, Duration2>::type>
222  operator+(const duration<Rep1, Period1>& lhs, const time_point<Clock, Duration2>& rhs);
223template <class Clock, class Duration1, class Rep2, class Period2>
224  time_point<Clock, typename common_type<Duration1, duration<Rep2, Period2>>::type>
225  operator-(const time_point<Clock, Duration1>& lhs, const duration<Rep2, Period2>& rhs);
226template <class Clock, class Duration1, class Duration2>
227  typename common_type<Duration1, Duration2>::type
228  operator-(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
229
230// time_point comparisons (all constexpr in C++14)
231template <class Clock, class Duration1, class Duration2>
232   bool operator==(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
233template <class Clock, class Duration1, class Duration2>
234   bool operator!=(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
235template <class Clock, class Duration1, class Duration2>
236   bool operator< (const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
237template <class Clock, class Duration1, class Duration2>
238   bool operator<=(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
239template <class Clock, class Duration1, class Duration2>
240   bool operator> (const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
241template <class Clock, class Duration1, class Duration2>
242   bool operator>=(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
243
244// time_point_cast (constexpr in C++14)
245
246template <class ToDuration, class Clock, class Duration>
247  time_point<Clock, ToDuration> time_point_cast(const time_point<Clock, Duration>& t);
248
249template <class ToDuration, class Clock, class Duration>
250    constexpr time_point<Clock, ToDuration>
251    floor(const time_point<Clock, Duration>& tp);                  // C++17
252
253template <class ToDuration, class Clock, class Duration>
254    constexpr time_point<Clock, ToDuration>
255    ceil(const time_point<Clock, Duration>& tp);                   // C++17
256
257template <class ToDuration, class Clock, class Duration>
258    constexpr time_point<Clock, ToDuration>
259    round(const time_point<Clock, Duration>& tp);                  // C++17
260
261template <class Rep, class Period>
262    constexpr duration<Rep, Period> abs(duration<Rep, Period> d);  // C++17
263
264// Clocks
265
266class system_clock
267{
268public:
269    typedef microseconds                     duration;
270    typedef duration::rep                    rep;
271    typedef duration::period                 period;
272    typedef chrono::time_point<system_clock> time_point;
273    static const bool is_steady =            false; // constexpr in C++14
274
275    static time_point now() noexcept;
276    static time_t     to_time_t  (const time_point& __t) noexcept;
277    static time_point from_time_t(time_t __t) noexcept;
278};
279
280template <class Duration>
281  using sys_time  = time_point<system_clock, Duration>; // C++20
282using sys_seconds = sys_time<seconds>;                  // C++20
283using sys_days    = sys_time<days>;                     // C++20
284
285class utc_clock;                                        // C++20
286
287template <class Duration>
288  using utc_time  = time_point<utc_clock, Duration>;    // C++20
289using utc_seconds = utc_time<seconds>;                  // C++20
290
291class tai_clock;                                        // C++20
292
293template <class Duration>
294  using tai_time  = time_point<tai_clock, Duration>;    // C++20
295using tai_seconds = tai_time<seconds>;                  // C++20
296
297class file_clock;                                       // C++20
298
299template<class Duration>
300  using file_time = time_point<file_clock, Duration>;   // C++20
301
302class steady_clock
303{
304public:
305    typedef nanoseconds                                   duration;
306    typedef duration::rep                                 rep;
307    typedef duration::period                              period;
308    typedef chrono::time_point<steady_clock, duration>    time_point;
309    static const bool is_steady =                         true; // constexpr in C++14
310
311    static time_point now() noexcept;
312};
313
314typedef steady_clock high_resolution_clock;
315
316// 25.7.8, local time           // C++20
317struct local_t {};
318template<class Duration>
319  using local_time  = time_point<local_t, Duration>;
320using local_seconds = local_time<seconds>;
321using local_days    = local_time<days>;
322
323// 25.7.9, time_point conversions template<class DestClock, class SourceClock>    // C++20
324struct clock_time_conversion;
325
326template<class DestClock, class SourceClock, class Duration>
327  auto clock_cast(const time_point<SourceClock, Duration>& t);
328
329// 25.8.2, class last_spec    // C++20
330struct last_spec;
331
332// 25.8.3, class day          // C++20
333
334class day;
335constexpr bool operator==(const day& x, const day& y) noexcept;
336constexpr bool operator!=(const day& x, const day& y) noexcept;
337constexpr bool operator< (const day& x, const day& y) noexcept;
338constexpr bool operator> (const day& x, const day& y) noexcept;
339constexpr bool operator<=(const day& x, const day& y) noexcept;
340constexpr bool operator>=(const day& x, const day& y) noexcept;
341constexpr day  operator+(const day&  x, const days& y) noexcept;
342constexpr day  operator+(const days& x, const day&  y) noexcept;
343constexpr day  operator-(const day&  x, const days& y) noexcept;
344constexpr days operator-(const day&  x, const day&  y) noexcept;
345
346// 25.8.4, class month    // C++20
347class month;
348constexpr bool operator==(const month& x, const month& y) noexcept;
349constexpr bool operator!=(const month& x, const month& y) noexcept;
350constexpr bool operator< (const month& x, const month& y) noexcept;
351constexpr bool operator> (const month& x, const month& y) noexcept;
352constexpr bool operator<=(const month& x, const month& y) noexcept;
353constexpr bool operator>=(const month& x, const month& y) noexcept;
354constexpr month  operator+(const month&  x, const months& y) noexcept;
355constexpr month  operator+(const months& x,  const month& y) noexcept;
356constexpr month  operator-(const month&  x, const months& y) noexcept;
357constexpr months operator-(const month&  x,  const month& y) noexcept;
358
359// 25.8.5, class year    // C++20
360class year;
361constexpr bool operator==(const year& x, const year& y) noexcept;
362constexpr bool operator!=(const year& x, const year& y) noexcept;
363constexpr bool operator< (const year& x, const year& y) noexcept;
364constexpr bool operator> (const year& x, const year& y) noexcept;
365constexpr bool operator<=(const year& x, const year& y) noexcept;
366constexpr bool operator>=(const year& x, const year& y) noexcept;
367constexpr year  operator+(const year&  x, const years& y) noexcept;
368constexpr year  operator+(const years& x, const year&  y) noexcept;
369constexpr year  operator-(const year&  x, const years& y) noexcept;
370constexpr years operator-(const year&  x, const year&  y) noexcept;
371
372// 25.8.6, class weekday    // C++20
373class weekday;
374
375constexpr bool operator==(const weekday& x, const weekday& y) noexcept;
376constexpr bool operator!=(const weekday& x, const weekday& y) noexcept;
377constexpr weekday operator+(const weekday& x, const days&    y) noexcept;
378constexpr weekday operator+(const days&    x, const weekday& y) noexcept;
379constexpr weekday operator-(const weekday& x, const days&    y) noexcept;
380constexpr days    operator-(const weekday& x, const weekday& y) noexcept;
381
382// 25.8.7, class weekday_indexed    // C++20
383
384class weekday_indexed;
385constexpr bool operator==(const weekday_indexed& x, const weekday_indexed& y) noexcept;
386constexpr bool operator!=(const weekday_indexed& x, const weekday_indexed& y) noexcept;
387
388// 25.8.8, class weekday_last    // C++20
389class weekday_last;
390
391constexpr bool operator==(const weekday_last& x, const weekday_last& y) noexcept;
392constexpr bool operator!=(const weekday_last& x, const weekday_last& y) noexcept;
393
394// 25.8.9, class month_day    // C++20
395class month_day;
396
397constexpr bool operator==(const month_day& x, const month_day& y) noexcept;
398constexpr bool operator!=(const month_day& x, const month_day& y) noexcept;
399constexpr bool operator< (const month_day& x, const month_day& y) noexcept;
400constexpr bool operator> (const month_day& x, const month_day& y) noexcept;
401constexpr bool operator<=(const month_day& x, const month_day& y) noexcept;
402constexpr bool operator>=(const month_day& x, const month_day& y) noexcept;
403
404
405// 25.8.10, class month_day_last    // C++20
406class month_day_last;
407
408constexpr bool operator==(const month_day_last& x, const month_day_last& y) noexcept;
409constexpr bool operator!=(const month_day_last& x, const month_day_last& y) noexcept;
410constexpr bool operator< (const month_day_last& x, const month_day_last& y) noexcept;
411constexpr bool operator> (const month_day_last& x, const month_day_last& y) noexcept;
412constexpr bool operator<=(const month_day_last& x, const month_day_last& y) noexcept;
413constexpr bool operator>=(const month_day_last& x, const month_day_last& y) noexcept;
414
415// 25.8.11, class month_weekday    // C++20
416class month_weekday;
417
418constexpr bool operator==(const month_weekday& x, const month_weekday& y) noexcept;
419constexpr bool operator!=(const month_weekday& x, const month_weekday& y) noexcept;
420
421// 25.8.12, class month_weekday_last    // C++20
422class month_weekday_last;
423
424constexpr bool operator==(const month_weekday_last& x, const month_weekday_last& y) noexcept;
425constexpr bool operator!=(const month_weekday_last& x, const month_weekday_last& y) noexcept;
426
427
428// 25.8.13, class year_month    // C++20
429class year_month;
430
431constexpr bool operator==(const year_month& x, const year_month& y) noexcept;
432constexpr bool operator!=(const year_month& x, const year_month& y) noexcept;
433constexpr bool operator< (const year_month& x, const year_month& y) noexcept;
434constexpr bool operator> (const year_month& x, const year_month& y) noexcept;
435constexpr bool operator<=(const year_month& x, const year_month& y) noexcept;
436constexpr bool operator>=(const year_month& x, const year_month& y) noexcept;
437
438constexpr year_month operator+(const year_month& ym, const months& dm) noexcept;
439constexpr year_month operator+(const months& dm, const year_month& ym) noexcept;
440constexpr year_month operator-(const year_month& ym, const months& dm) noexcept;
441constexpr months operator-(const year_month& x, const year_month& y) noexcept;
442constexpr year_month operator+(const year_month& ym, const years& dy) noexcept;
443constexpr year_month operator+(const years& dy, const year_month& ym) noexcept;
444constexpr year_month operator-(const year_month& ym, const years& dy) noexcept;
445
446// 25.8.14, class year_month_day class    // C++20
447year_month_day;
448
449constexpr bool operator==(const year_month_day& x, const year_month_day& y) noexcept;
450constexpr bool operator!=(const year_month_day& x, const year_month_day& y) noexcept;
451constexpr bool operator< (const year_month_day& x, const year_month_day& y) noexcept;
452constexpr bool operator> (const year_month_day& x, const year_month_day& y) noexcept;
453constexpr bool operator<=(const year_month_day& x, const year_month_day& y) noexcept;
454constexpr bool operator>=(const year_month_day& x, const year_month_day& y) noexcept;
455
456constexpr year_month_day operator+(const year_month_day& ymd, const months& dm) noexcept;
457constexpr year_month_day operator+(const months& dm, const year_month_day& ymd) noexcept;
458constexpr year_month_day operator+(const year_month_day& ymd, const years& dy) noexcept;
459constexpr year_month_day operator+(const years& dy, const year_month_day& ymd) noexcept;
460constexpr year_month_day operator-(const year_month_day& ymd, const months& dm) noexcept;
461constexpr year_month_day operator-(const year_month_day& ymd, const years& dy) noexcept;
462
463
464// 25.8.15, class year_month_day_last    // C++20
465class year_month_day_last;
466
467constexpr bool operator==(const year_month_day_last& x,
468                          const year_month_day_last& y) noexcept;
469constexpr bool operator!=(const year_month_day_last& x,
470                          const year_month_day_last& y) noexcept;
471constexpr bool operator< (const year_month_day_last& x,
472                          const year_month_day_last& y) noexcept;
473constexpr bool operator> (const year_month_day_last& x,
474                          const year_month_day_last& y) noexcept;
475constexpr bool operator<=(const year_month_day_last& x,
476                          const year_month_day_last& y) noexcept;
477constexpr bool operator>=(const year_month_day_last& x,
478                          const year_month_day_last& y) noexcept;
479
480constexpr year_month_day_last
481  operator+(const year_month_day_last& ymdl, const months& dm) noexcept;
482constexpr year_month_day_last
483  operator+(const months& dm, const year_month_day_last& ymdl) noexcept;
484constexpr year_month_day_last
485  operator+(const year_month_day_last& ymdl, const years& dy) noexcept;
486constexpr year_month_day_last
487  operator+(const years& dy, const year_month_day_last& ymdl) noexcept;
488constexpr year_month_day_last
489  operator-(const year_month_day_last& ymdl, const months& dm) noexcept;
490constexpr year_month_day_last
491  operator-(const year_month_day_last& ymdl, const years& dy) noexcept;
492
493// 25.8.16, class year_month_weekday    // C++20
494class year_month_weekday;
495
496constexpr bool operator==(const year_month_weekday& x,
497                          const year_month_weekday& y) noexcept;
498constexpr bool operator!=(const year_month_weekday& x,
499                          const year_month_weekday& y) noexcept;
500
501constexpr year_month_weekday
502  operator+(const year_month_weekday& ymwd, const months& dm) noexcept;
503constexpr year_month_weekday
504  operator+(const months& dm, const year_month_weekday& ymwd) noexcept;
505constexpr year_month_weekday
506  operator+(const year_month_weekday& ymwd, const years& dy) noexcept;
507constexpr year_month_weekday
508  operator+(const years& dy, const year_month_weekday& ymwd) noexcept;
509constexpr year_month_weekday
510  operator-(const year_month_weekday& ymwd, const months& dm) noexcept;
511constexpr year_month_weekday
512  operator-(const year_month_weekday& ymwd, const years& dy) noexcept;
513
514// 25.8.17, class year_month_weekday_last    // C++20
515class year_month_weekday_last;
516
517constexpr bool operator==(const year_month_weekday_last& x,
518                          const year_month_weekday_last& y) noexcept;
519constexpr bool operator!=(const year_month_weekday_last& x,
520                          const year_month_weekday_last& y) noexcept;
521constexpr year_month_weekday_last
522  operator+(const year_month_weekday_last& ymwdl, const months& dm) noexcept;
523constexpr year_month_weekday_last
524  operator+(const months& dm, const year_month_weekday_last& ymwdl) noexcept;
525constexpr year_month_weekday_last
526  operator+(const year_month_weekday_last& ymwdl, const years& dy) noexcept;
527constexpr year_month_weekday_last
528  operator+(const years& dy, const year_month_weekday_last& ymwdl) noexcept;
529constexpr year_month_weekday_last
530  operator-(const year_month_weekday_last& ymwdl, const months& dm) noexcept;
531constexpr year_month_weekday_last
532  operator-(const year_month_weekday_last& ymwdl, const years& dy) noexcept;
533
534// 25.8.18, civil calendar conventional syntax operators    // C++20
535constexpr year_month
536  operator/(const year& y, const month& m) noexcept;
537constexpr year_month
538  operator/(const year& y, int m) noexcept;
539constexpr month_day
540  operator/(const month& m, const day& d) noexcept;
541constexpr month_day
542  operator/(const month& m, int d) noexcept;
543constexpr month_day
544  operator/(int m, const day& d) noexcept;
545constexpr month_day
546  operator/(const day& d, const month& m) noexcept;
547constexpr month_day
548  operator/(const day& d, int m) noexcept;
549constexpr month_day_last
550  operator/(const month& m, last_spec) noexcept;
551constexpr month_day_last
552  operator/(int m, last_spec) noexcept;
553constexpr month_day_last
554  operator/(last_spec, const month& m) noexcept;
555constexpr month_day_last
556  operator/(last_spec, int m) noexcept;
557constexpr month_weekday
558  operator/(const month& m, const weekday_indexed& wdi) noexcept;
559constexpr month_weekday
560  operator/(int m, const weekday_indexed& wdi) noexcept;
561constexpr month_weekday
562  operator/(const weekday_indexed& wdi, const month& m) noexcept;
563constexpr month_weekday
564  operator/(const weekday_indexed& wdi, int m) noexcept;
565constexpr month_weekday_last
566  operator/(const month& m, const weekday_last& wdl) noexcept;
567constexpr month_weekday_last
568  operator/(int m, const weekday_last& wdl) noexcept;
569constexpr month_weekday_last
570  operator/(const weekday_last& wdl, const month& m) noexcept;
571constexpr month_weekday_last
572  operator/(const weekday_last& wdl, int m) noexcept;
573constexpr year_month_day
574  operator/(const year_month& ym, const day& d) noexcept;
575constexpr year_month_day
576  operator/(const year_month& ym, int d) noexcept;
577constexpr year_month_day
578  operator/(const year& y, const month_day& md) noexcept;
579constexpr year_month_day
580  operator/(int y, const month_day& md) noexcept;
581constexpr year_month_day
582  operator/(const month_day& md, const year& y) noexcept;
583constexpr year_month_day
584  operator/(const month_day& md, int y) noexcept;
585constexpr year_month_day_last
586  operator/(const year_month& ym, last_spec) noexcept;
587constexpr year_month_day_last
588  operator/(const year& y, const month_day_last& mdl) noexcept;
589constexpr year_month_day_last
590  operator/(int y, const month_day_last& mdl) noexcept;
591constexpr year_month_day_last
592  operator/(const month_day_last& mdl, const year& y) noexcept;
593constexpr year_month_day_last
594  operator/(const month_day_last& mdl, int y) noexcept;
595constexpr year_month_weekday
596  operator/(const year_month& ym, const weekday_indexed& wdi) noexcept;
597constexpr year_month_weekday
598  operator/(const year& y, const month_weekday& mwd) noexcept;
599constexpr year_month_weekday
600  operator/(int y, const month_weekday& mwd) noexcept;
601constexpr year_month_weekday
602  operator/(const month_weekday& mwd, const year& y) noexcept;
603constexpr year_month_weekday
604  operator/(const month_weekday& mwd, int y) noexcept;
605constexpr year_month_weekday_last
606  operator/(const year_month& ym, const weekday_last& wdl) noexcept;
607constexpr year_month_weekday_last
608  operator/(const year& y, const month_weekday_last& mwdl) noexcept;
609constexpr year_month_weekday_last
610  operator/(int y, const month_weekday_last& mwdl) noexcept;
611constexpr year_month_weekday_last
612  operator/(const month_weekday_last& mwdl, const year& y) noexcept;
613constexpr year_month_weekday_last
614  operator/(const month_weekday_last& mwdl, int y) noexcept;
615
616// 25.9, class template time_of_day    // C++20
617template<class Duration> class time_of_day;
618
619template<> class time_of_day<hours>;
620template<> class time_of_day<minutes>;
621template<> class time_of_day<seconds>;
622template<class Rep, class Period> class time_of_day<duration<Rep, Period>>;
623
624// 25.10.2, time zone database     // C++20
625struct tzdb;
626class tzdb_list;
627
628// 25.10.2.3, time zone database access    // C++20
629const tzdb& get_tzdb();
630tzdb_list& get_tzdb_list();
631const time_zone* locate_zone(string_view tz_name);
632const time_zone* current_zone();
633
634// 25.10.2.4, remote time zone database support    // C++20
635const tzdb& reload_tzdb();
636string remote_version();
637
638// 25.10.3, exception classes    // C++20
639class nonexistent_local_time;
640class ambiguous_local_time;
641
642// 25.10.4, information classes    // C++20
643struct sys_info;
644struct local_info;
645
646// 25.10.5, class time_zone    // C++20
647enum class choose {earliest, latest};
648class time_zone;
649bool operator==(const time_zone& x, const time_zone& y) noexcept;
650bool operator!=(const time_zone& x, const time_zone& y) noexcept;
651bool operator<(const time_zone& x, const time_zone& y) noexcept;
652bool operator>(const time_zone& x, const time_zone& y) noexcept;
653bool operator<=(const time_zone& x, const time_zone& y) noexcept;
654bool operator>=(const time_zone& x, const time_zone& y) noexcept;
655
656// 25.10.6, class template zoned_traits    // C++20
657template<class T> struct zoned_traits;
658
659// 25.10.7, class template zoned_time    // C++20
660template<class Duration, class TimeZonePtr = const time_zone*> class zoned_time;
661using zoned_seconds = zoned_time<seconds>;
662
663template<class Duration1, class Duration2, class TimeZonePtr>
664  bool operator==(const zoned_time<Duration1, TimeZonePtr>& x,
665                  const zoned_time<Duration2, TimeZonePtr>& y);
666template<class Duration1, class Duration2, class TimeZonePtr>
667  bool operator!=(const zoned_time<Duration1, TimeZonePtr>& x,
668                  const zoned_time<Duration2, TimeZonePtr>& y);
669
670// 25.10.8, leap second support    // C++20
671class leap;
672
673bool operator==(const leap& x, const leap& y);
674bool operator!=(const leap& x, const leap& y);
675bool operator< (const leap& x, const leap& y);
676bool operator> (const leap& x, const leap& y);
677bool operator<=(const leap& x, const leap& y);
678bool operator>=(const leap& x, const leap& y);
679template<class Duration>
680  bool operator==(const leap& x, const sys_time<Duration>& y);
681template<class Duration>
682  bool operator==(const sys_time<Duration>& x, const leap& y);
683template<class Duration>
684  bool operator!=(const leap& x, const sys_time<Duration>& y);
685template<class Duration>
686  bool operator!=(const sys_time<Duration>& x, const leap& y);
687template<class Duration>
688  bool operator< (const leap& x, const sys_time<Duration>& y);
689template<class Duration>
690  bool operator< (const sys_time<Duration>& x, const leap& y);
691template<class Duration>
692  bool operator> (const leap& x, const sys_time<Duration>& y);
693template<class Duration>
694  bool operator> (const sys_time<Duration>& x, const leap& y);
695template<class Duration>
696  bool operator<=(const leap& x, const sys_time<Duration>& y);
697template<class Duration>
698  bool operator<=(const sys_time<Duration>& x, const leap& y);
699template<class Duration>
700  bool operator>=(const leap& x, const sys_time<Duration>& y);
701template<class Duration>
702  bool operator>=(const sys_time<Duration>& x, const leap& y);
703
704// 25.10.9, class link    // C++20
705class link;
706bool operator==(const link& x, const link& y);
707bool operator!=(const link& x, const link& y);
708bool operator< (const link& x, const link& y);
709bool operator> (const link& x, const link& y);
710bool operator<=(const link& x, const link& y);
711bool operator>=(const link& x, const link& y);
712
713// 25.11, formatting    // C++20
714template<class charT, class Streamable>
715  basic_string<charT>
716    format(const charT* fmt, const Streamable& s);
717
718template<class charT, class Streamable>
719  basic_string<charT>
720    format(const locale& loc, const charT* fmt, const Streamable& s);
721
722template<class charT, class traits, class Alloc, class Streamable>
723  basic_string<charT, traits, Alloc>
724    format(const basic_string<charT, traits, Alloc>& fmt, const Streamable& s);
725
726template<class charT, class traits, class Alloc, class Streamable>
727  basic_string<charT, traits, Alloc>
728    format(const locale& loc, const basic_string<charT, traits, Alloc>& fmt,
729           const Streamable& s);
730
731// 25.12, parsing    // C++20
732template<class charT, class traits, class Alloc, class Parsable>
733unspecified
734    parse(const basic_string<charT, traits, Alloc>& format, Parsable& tp);
735
736template<class charT, class traits, class Alloc, class Parsable>
737unspecified
738    parse(const basic_string<charT, traits, Alloc>& format, Parsable& tp,
739          basic_string<charT, traits, Alloc>& abbrev);
740
741template<class charT, class traits, class Alloc, class Parsable>
742unspecified
743    parse(const basic_string<charT, traits, Alloc>& format, Parsable& tp,
744          minutes& offset);
745
746template<class charT, class traits, class Alloc, class Parsable>
747unspecified
748    parse(const basic_string<charT, traits, Alloc>& format, Parsable& tp,
749          basic_string<charT, traits, Alloc>& abbrev, minutes& offset);
750
751// calendrical constants
752inline constexpr last_spec                              last{};       // C++20
753inline constexpr chrono::weekday                        Sunday{0};    // C++20
754inline constexpr chrono::weekday                        Monday{1};    // C++20
755inline constexpr chrono::weekday                        Tuesday{2};   // C++20
756inline constexpr chrono::weekday                        Wednesday{3}; // C++20
757inline constexpr chrono::weekday                        Thursday{4};  // C++20
758inline constexpr chrono::weekday                        Friday{5};    // C++20
759inline constexpr chrono::weekday                        Saturday{6};  // C++20
760
761inline constexpr chrono::month                          January{1};   // C++20
762inline constexpr chrono::month                          February{2};  // C++20
763inline constexpr chrono::month                          March{3};     // C++20
764inline constexpr chrono::month                          April{4};     // C++20
765inline constexpr chrono::month                          May{5};       // C++20
766inline constexpr chrono::month                          June{6};      // C++20
767inline constexpr chrono::month                          July{7};      // C++20
768inline constexpr chrono::month                          August{8};    // C++20
769inline constexpr chrono::month                          September{9}; // C++20
770inline constexpr chrono::month                          October{10};  // C++20
771inline constexpr chrono::month                          November{11}; // C++20
772inline constexpr chrono::month                          December{12}; // C++20
773}  // chrono
774
775inline namespace literals {
776  inline namespace chrono_literals {
777constexpr chrono::hours                                 operator ""h(unsigned long long); // C++14
778constexpr chrono::duration<unspecified , ratio<3600,1>> operator ""h(long double); // C++14
779constexpr chrono::minutes                               operator ""min(unsigned long long); // C++14
780constexpr chrono::duration<unspecified , ratio<60,1>>   operator ""min(long double); // C++14
781constexpr chrono::seconds                               operator ""s(unsigned long long); // C++14
782constexpr chrono::duration<unspecified >                operator ""s(long double); // C++14
783constexpr chrono::milliseconds                          operator ""ms(unsigned long long); // C++14
784constexpr chrono::duration<unspecified , milli>         operator ""ms(long double); // C++14
785constexpr chrono::microseconds                          operator ""us(unsigned long long); // C++14
786constexpr chrono::duration<unspecified , micro>         operator ""us(long double); // C++14
787constexpr chrono::nanoseconds                           operator ""ns(unsigned long long); // C++14
788constexpr chrono::duration<unspecified , nano>          operator ""ns(long double); // C++14
789constexpr chrono::day                                   operator ""d(unsigned long long d) noexcept; // C++20
790constexpr chrono::year                                  operator ""y(unsigned long long y) noexcept; // C++20
791}  // chrono_literals
792}  // literals
793
794}  // std
795*/
796
797#include <__config>
798#include <ctime>
799#include <type_traits>
800#include <ratio>
801#include <limits>
802#include <version>
803
804#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
805#pragma GCC system_header
806#endif
807
808_LIBCPP_PUSH_MACROS
809#include <__undef_macros>
810
811
812_LIBCPP_BEGIN_NAMESPACE_STD
813
814namespace chrono
815{
816
817template <class _Rep, class _Period = ratio<1> > class _LIBCPP_TEMPLATE_VIS duration;
818
819template <class _Tp>
820struct __is_duration : false_type {};
821
822template <class _Rep, class _Period>
823struct __is_duration<duration<_Rep, _Period> > : true_type  {};
824
825template <class _Rep, class _Period>
826struct __is_duration<const duration<_Rep, _Period> > : true_type  {};
827
828template <class _Rep, class _Period>
829struct __is_duration<volatile duration<_Rep, _Period> > : true_type  {};
830
831template <class _Rep, class _Period>
832struct __is_duration<const volatile duration<_Rep, _Period> > : true_type  {};
833
834} // chrono
835
836template <class _Rep1, class _Period1, class _Rep2, class _Period2>
837struct _LIBCPP_TEMPLATE_VIS common_type<chrono::duration<_Rep1, _Period1>,
838                                         chrono::duration<_Rep2, _Period2> >
839{
840    typedef chrono::duration<typename common_type<_Rep1, _Rep2>::type,
841                             typename __ratio_gcd<_Period1, _Period2>::type> type;
842};
843
844namespace chrono {
845
846// duration_cast
847
848template <class _FromDuration, class _ToDuration,
849          class _Period = typename ratio_divide<typename _FromDuration::period, typename _ToDuration::period>::type,
850          bool = _Period::num == 1,
851          bool = _Period::den == 1>
852struct __duration_cast;
853
854template <class _FromDuration, class _ToDuration, class _Period>
855struct __duration_cast<_FromDuration, _ToDuration, _Period, true, true>
856{
857    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
858    _ToDuration operator()(const _FromDuration& __fd) const
859    {
860        return _ToDuration(static_cast<typename _ToDuration::rep>(__fd.count()));
861    }
862};
863
864template <class _FromDuration, class _ToDuration, class _Period>
865struct __duration_cast<_FromDuration, _ToDuration, _Period, true, false>
866{
867    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
868    _ToDuration operator()(const _FromDuration& __fd) const
869    {
870        typedef typename common_type<typename _ToDuration::rep, typename _FromDuration::rep, intmax_t>::type _Ct;
871        return _ToDuration(static_cast<typename _ToDuration::rep>(
872                           static_cast<_Ct>(__fd.count()) / static_cast<_Ct>(_Period::den)));
873    }
874};
875
876template <class _FromDuration, class _ToDuration, class _Period>
877struct __duration_cast<_FromDuration, _ToDuration, _Period, false, true>
878{
879    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
880    _ToDuration operator()(const _FromDuration& __fd) const
881    {
882        typedef typename common_type<typename _ToDuration::rep, typename _FromDuration::rep, intmax_t>::type _Ct;
883        return _ToDuration(static_cast<typename _ToDuration::rep>(
884                           static_cast<_Ct>(__fd.count()) * static_cast<_Ct>(_Period::num)));
885    }
886};
887
888template <class _FromDuration, class _ToDuration, class _Period>
889struct __duration_cast<_FromDuration, _ToDuration, _Period, false, false>
890{
891    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
892    _ToDuration operator()(const _FromDuration& __fd) const
893    {
894        typedef typename common_type<typename _ToDuration::rep, typename _FromDuration::rep, intmax_t>::type _Ct;
895        return _ToDuration(static_cast<typename _ToDuration::rep>(
896                           static_cast<_Ct>(__fd.count()) * static_cast<_Ct>(_Period::num)
897                                                          / static_cast<_Ct>(_Period::den)));
898    }
899};
900
901template <class _ToDuration, class _Rep, class _Period>
902inline _LIBCPP_INLINE_VISIBILITY
903_LIBCPP_CONSTEXPR
904typename enable_if
905<
906    __is_duration<_ToDuration>::value,
907    _ToDuration
908>::type
909duration_cast(const duration<_Rep, _Period>& __fd)
910{
911    return __duration_cast<duration<_Rep, _Period>, _ToDuration>()(__fd);
912}
913
914template <class _Rep>
915struct _LIBCPP_TEMPLATE_VIS treat_as_floating_point : is_floating_point<_Rep> {};
916
917#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_VARIABLE_TEMPLATES)
918template <class _Rep>
919_LIBCPP_INLINE_VAR _LIBCPP_CONSTEXPR bool treat_as_floating_point_v
920    = treat_as_floating_point<_Rep>::value;
921#endif
922
923template <class _Rep>
924struct _LIBCPP_TEMPLATE_VIS duration_values
925{
926public:
927    _LIBCPP_INLINE_VISIBILITY static _LIBCPP_CONSTEXPR _Rep zero() {return _Rep(0);}
928    _LIBCPP_INLINE_VISIBILITY static _LIBCPP_CONSTEXPR _Rep max()  {return numeric_limits<_Rep>::max();}
929    _LIBCPP_INLINE_VISIBILITY static _LIBCPP_CONSTEXPR _Rep min()  {return numeric_limits<_Rep>::lowest();}
930};
931
932#if _LIBCPP_STD_VER > 14
933template <class _ToDuration, class _Rep, class _Period>
934inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
935typename enable_if
936<
937    __is_duration<_ToDuration>::value,
938    _ToDuration
939>::type
940floor(const duration<_Rep, _Period>& __d)
941{
942    _ToDuration __t = duration_cast<_ToDuration>(__d);
943    if (__t > __d)
944        __t = __t - _ToDuration{1};
945    return __t;
946}
947
948template <class _ToDuration, class _Rep, class _Period>
949inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
950typename enable_if
951<
952    __is_duration<_ToDuration>::value,
953    _ToDuration
954>::type
955ceil(const duration<_Rep, _Period>& __d)
956{
957    _ToDuration __t = duration_cast<_ToDuration>(__d);
958    if (__t < __d)
959        __t = __t + _ToDuration{1};
960    return __t;
961}
962
963template <class _ToDuration, class _Rep, class _Period>
964inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
965typename enable_if
966<
967    __is_duration<_ToDuration>::value,
968    _ToDuration
969>::type
970round(const duration<_Rep, _Period>& __d)
971{
972    _ToDuration __lower = floor<_ToDuration>(__d);
973    _ToDuration __upper = __lower + _ToDuration{1};
974    auto __lowerDiff = __d - __lower;
975    auto __upperDiff = __upper - __d;
976    if (__lowerDiff < __upperDiff)
977        return __lower;
978    if (__lowerDiff > __upperDiff)
979        return __upper;
980    return __lower.count() & 1 ? __upper : __lower;
981}
982#endif
983
984// duration
985
986template <class _Rep, class _Period>
987class _LIBCPP_TEMPLATE_VIS duration
988{
989    static_assert(!__is_duration<_Rep>::value, "A duration representation can not be a duration");
990    static_assert(__is_ratio<_Period>::value, "Second template parameter of duration must be a std::ratio");
991    static_assert(_Period::num > 0, "duration period must be positive");
992
993    template <class _R1, class _R2>
994    struct __no_overflow
995    {
996    private:
997        static const intmax_t __gcd_n1_n2 = __static_gcd<_R1::num, _R2::num>::value;
998        static const intmax_t __gcd_d1_d2 = __static_gcd<_R1::den, _R2::den>::value;
999        static const intmax_t __n1 = _R1::num / __gcd_n1_n2;
1000        static const intmax_t __d1 = _R1::den / __gcd_d1_d2;
1001        static const intmax_t __n2 = _R2::num / __gcd_n1_n2;
1002        static const intmax_t __d2 = _R2::den / __gcd_d1_d2;
1003        static const intmax_t max = -((intmax_t(1) << (sizeof(intmax_t) * CHAR_BIT - 1)) + 1);
1004
1005        template <intmax_t _Xp, intmax_t _Yp, bool __overflow>
1006        struct __mul    // __overflow == false
1007        {
1008            static const intmax_t value = _Xp * _Yp;
1009        };
1010
1011        template <intmax_t _Xp, intmax_t _Yp>
1012        struct __mul<_Xp, _Yp, true>
1013        {
1014            static const intmax_t value = 1;
1015        };
1016
1017    public:
1018        static const bool value = (__n1 <= max / __d2) && (__n2 <= max / __d1);
1019        typedef ratio<__mul<__n1, __d2, !value>::value,
1020                      __mul<__n2, __d1, !value>::value> type;
1021    };
1022
1023public:
1024    typedef _Rep rep;
1025    typedef typename _Period::type period;
1026private:
1027    rep __rep_;
1028public:
1029
1030    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
1031#ifndef _LIBCPP_CXX03_LANG
1032        duration() = default;
1033#else
1034        duration() {}
1035#endif
1036
1037    template <class _Rep2>
1038        _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
1039        explicit duration(const _Rep2& __r,
1040            typename enable_if
1041            <
1042               is_convertible<_Rep2, rep>::value &&
1043               (treat_as_floating_point<rep>::value ||
1044               !treat_as_floating_point<_Rep2>::value)
1045            >::type* = 0)
1046                : __rep_(__r) {}
1047
1048    // conversions
1049    template <class _Rep2, class _Period2>
1050        _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
1051        duration(const duration<_Rep2, _Period2>& __d,
1052            typename enable_if
1053            <
1054                __no_overflow<_Period2, period>::value && (
1055                treat_as_floating_point<rep>::value ||
1056                (__no_overflow<_Period2, period>::type::den == 1 &&
1057                 !treat_as_floating_point<_Rep2>::value))
1058            >::type* = 0)
1059                : __rep_(_VSTD::chrono::duration_cast<duration>(__d).count()) {}
1060
1061    // observer
1062
1063    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR rep count() const {return __rep_;}
1064
1065    // arithmetic
1066
1067    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR typename common_type<duration>::type operator+() const {return typename common_type<duration>::type(*this);}
1068    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR typename common_type<duration>::type operator-() const {return typename common_type<duration>::type(-__rep_);}
1069    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration& operator++()      {++__rep_; return *this;}
1070    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration  operator++(int)   {return duration(__rep_++);}
1071    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration& operator--()      {--__rep_; return *this;}
1072    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration  operator--(int)   {return duration(__rep_--);}
1073
1074    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration& operator+=(const duration& __d) {__rep_ += __d.count(); return *this;}
1075    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration& operator-=(const duration& __d) {__rep_ -= __d.count(); return *this;}
1076
1077    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration& operator*=(const rep& rhs) {__rep_ *= rhs; return *this;}
1078    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration& operator/=(const rep& rhs) {__rep_ /= rhs; return *this;}
1079    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration& operator%=(const rep& rhs) {__rep_ %= rhs; return *this;}
1080    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 duration& operator%=(const duration& rhs) {__rep_ %= rhs.count(); return *this;}
1081
1082    // special values
1083
1084    _LIBCPP_INLINE_VISIBILITY static _LIBCPP_CONSTEXPR duration zero() {return duration(duration_values<rep>::zero());}
1085    _LIBCPP_INLINE_VISIBILITY static _LIBCPP_CONSTEXPR duration min()  {return duration(duration_values<rep>::min());}
1086    _LIBCPP_INLINE_VISIBILITY static _LIBCPP_CONSTEXPR duration max()  {return duration(duration_values<rep>::max());}
1087};
1088
1089typedef duration<long long,         nano> nanoseconds;
1090typedef duration<long long,        micro> microseconds;
1091typedef duration<long long,        milli> milliseconds;
1092typedef duration<long long              > seconds;
1093typedef duration<     long, ratio<  60> > minutes;
1094typedef duration<     long, ratio<3600> > hours;
1095#if _LIBCPP_STD_VER > 17
1096typedef duration<     int, ratio_multiply<ratio<24>, hours::period>>         days;
1097typedef duration<     int, ratio_multiply<ratio<7>,   days::period>>         weeks;
1098typedef duration<     int, ratio_multiply<ratio<146097, 400>, days::period>> years;
1099typedef duration<     int, ratio_divide<years::period, ratio<12>>>           months;
1100#endif
1101// Duration ==
1102
1103template <class _LhsDuration, class _RhsDuration>
1104struct __duration_eq
1105{
1106    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
1107    bool operator()(const _LhsDuration& __lhs, const _RhsDuration& __rhs) const
1108        {
1109            typedef typename common_type<_LhsDuration, _RhsDuration>::type _Ct;
1110            return _Ct(__lhs).count() == _Ct(__rhs).count();
1111        }
1112};
1113
1114template <class _LhsDuration>
1115struct __duration_eq<_LhsDuration, _LhsDuration>
1116{
1117    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
1118    bool operator()(const _LhsDuration& __lhs, const _LhsDuration& __rhs) const
1119        {return __lhs.count() == __rhs.count();}
1120};
1121
1122template <class _Rep1, class _Period1, class _Rep2, class _Period2>
1123inline _LIBCPP_INLINE_VISIBILITY
1124_LIBCPP_CONSTEXPR
1125bool
1126operator==(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
1127{
1128    return __duration_eq<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >()(__lhs, __rhs);
1129}
1130
1131// Duration !=
1132
1133template <class _Rep1, class _Period1, class _Rep2, class _Period2>
1134inline _LIBCPP_INLINE_VISIBILITY
1135_LIBCPP_CONSTEXPR
1136bool
1137operator!=(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
1138{
1139    return !(__lhs == __rhs);
1140}
1141
1142// Duration <
1143
1144template <class _LhsDuration, class _RhsDuration>
1145struct __duration_lt
1146{
1147    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
1148    bool operator()(const _LhsDuration& __lhs, const _RhsDuration& __rhs) const
1149        {
1150            typedef typename common_type<_LhsDuration, _RhsDuration>::type _Ct;
1151            return _Ct(__lhs).count() < _Ct(__rhs).count();
1152        }
1153};
1154
1155template <class _LhsDuration>
1156struct __duration_lt<_LhsDuration, _LhsDuration>
1157{
1158    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
1159    bool operator()(const _LhsDuration& __lhs, const _LhsDuration& __rhs) const
1160        {return __lhs.count() < __rhs.count();}
1161};
1162
1163template <class _Rep1, class _Period1, class _Rep2, class _Period2>
1164inline _LIBCPP_INLINE_VISIBILITY
1165_LIBCPP_CONSTEXPR
1166bool
1167operator< (const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
1168{
1169    return __duration_lt<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >()(__lhs, __rhs);
1170}
1171
1172// Duration >
1173
1174template <class _Rep1, class _Period1, class _Rep2, class _Period2>
1175inline _LIBCPP_INLINE_VISIBILITY
1176_LIBCPP_CONSTEXPR
1177bool
1178operator> (const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
1179{
1180    return __rhs < __lhs;
1181}
1182
1183// Duration <=
1184
1185template <class _Rep1, class _Period1, class _Rep2, class _Period2>
1186inline _LIBCPP_INLINE_VISIBILITY
1187_LIBCPP_CONSTEXPR
1188bool
1189operator<=(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
1190{
1191    return !(__rhs < __lhs);
1192}
1193
1194// Duration >=
1195
1196template <class _Rep1, class _Period1, class _Rep2, class _Period2>
1197inline _LIBCPP_INLINE_VISIBILITY
1198_LIBCPP_CONSTEXPR
1199bool
1200operator>=(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
1201{
1202    return !(__lhs < __rhs);
1203}
1204
1205// Duration +
1206
1207template <class _Rep1, class _Period1, class _Rep2, class _Period2>
1208inline _LIBCPP_INLINE_VISIBILITY
1209_LIBCPP_CONSTEXPR
1210typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type
1211operator+(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
1212{
1213    typedef typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type _Cd;
1214    return _Cd(_Cd(__lhs).count() + _Cd(__rhs).count());
1215}
1216
1217// Duration -
1218
1219template <class _Rep1, class _Period1, class _Rep2, class _Period2>
1220inline _LIBCPP_INLINE_VISIBILITY
1221_LIBCPP_CONSTEXPR
1222typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type
1223operator-(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
1224{
1225    typedef typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type _Cd;
1226    return _Cd(_Cd(__lhs).count() - _Cd(__rhs).count());
1227}
1228
1229// Duration *
1230
1231template <class _Rep1, class _Period, class _Rep2>
1232inline _LIBCPP_INLINE_VISIBILITY
1233_LIBCPP_CONSTEXPR
1234typename enable_if
1235<
1236    is_convertible<_Rep2, typename common_type<_Rep1, _Rep2>::type>::value,
1237    duration<typename common_type<_Rep1, _Rep2>::type, _Period>
1238>::type
1239operator*(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
1240{
1241    typedef typename common_type<_Rep1, _Rep2>::type _Cr;
1242    typedef duration<_Cr, _Period> _Cd;
1243    return _Cd(_Cd(__d).count() * static_cast<_Cr>(__s));
1244}
1245
1246template <class _Rep1, class _Period, class _Rep2>
1247inline _LIBCPP_INLINE_VISIBILITY
1248_LIBCPP_CONSTEXPR
1249typename enable_if
1250<
1251    is_convertible<_Rep1, typename common_type<_Rep1, _Rep2>::type>::value,
1252    duration<typename common_type<_Rep1, _Rep2>::type, _Period>
1253>::type
1254operator*(const _Rep1& __s, const duration<_Rep2, _Period>& __d)
1255{
1256    return __d * __s;
1257}
1258
1259// Duration /
1260
1261template <class _Duration, class _Rep, bool = __is_duration<_Rep>::value>
1262struct __duration_divide_result
1263{
1264};
1265
1266template <class _Duration, class _Rep2,
1267    bool = is_convertible<_Rep2,
1268                          typename common_type<typename _Duration::rep, _Rep2>::type>::value>
1269struct __duration_divide_imp
1270{
1271};
1272
1273template <class _Rep1, class _Period, class _Rep2>
1274struct __duration_divide_imp<duration<_Rep1, _Period>, _Rep2, true>
1275{
1276    typedef duration<typename common_type<_Rep1, _Rep2>::type, _Period> type;
1277};
1278
1279template <class _Rep1, class _Period, class _Rep2>
1280struct __duration_divide_result<duration<_Rep1, _Period>, _Rep2, false>
1281    : __duration_divide_imp<duration<_Rep1, _Period>, _Rep2>
1282{
1283};
1284
1285template <class _Rep1, class _Period, class _Rep2>
1286inline _LIBCPP_INLINE_VISIBILITY
1287_LIBCPP_CONSTEXPR
1288typename __duration_divide_result<duration<_Rep1, _Period>, _Rep2>::type
1289operator/(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
1290{
1291    typedef typename common_type<_Rep1, _Rep2>::type _Cr;
1292    typedef duration<_Cr, _Period> _Cd;
1293    return _Cd(_Cd(__d).count() / static_cast<_Cr>(__s));
1294}
1295
1296template <class _Rep1, class _Period1, class _Rep2, class _Period2>
1297inline _LIBCPP_INLINE_VISIBILITY
1298_LIBCPP_CONSTEXPR
1299typename common_type<_Rep1, _Rep2>::type
1300operator/(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
1301{
1302    typedef typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type _Ct;
1303    return _Ct(__lhs).count() / _Ct(__rhs).count();
1304}
1305
1306// Duration %
1307
1308template <class _Rep1, class _Period, class _Rep2>
1309inline _LIBCPP_INLINE_VISIBILITY
1310_LIBCPP_CONSTEXPR
1311typename __duration_divide_result<duration<_Rep1, _Period>, _Rep2>::type
1312operator%(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
1313{
1314    typedef typename common_type<_Rep1, _Rep2>::type _Cr;
1315    typedef duration<_Cr, _Period> _Cd;
1316    return _Cd(_Cd(__d).count() % static_cast<_Cr>(__s));
1317}
1318
1319template <class _Rep1, class _Period1, class _Rep2, class _Period2>
1320inline _LIBCPP_INLINE_VISIBILITY
1321_LIBCPP_CONSTEXPR
1322typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type
1323operator%(const duration<_Rep1, _Period1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
1324{
1325    typedef typename common_type<_Rep1, _Rep2>::type _Cr;
1326    typedef typename common_type<duration<_Rep1, _Period1>, duration<_Rep2, _Period2> >::type _Cd;
1327    return _Cd(static_cast<_Cr>(_Cd(__lhs).count()) % static_cast<_Cr>(_Cd(__rhs).count()));
1328}
1329
1330//////////////////////////////////////////////////////////
1331///////////////////// time_point /////////////////////////
1332//////////////////////////////////////////////////////////
1333
1334template <class _Clock, class _Duration = typename _Clock::duration>
1335class _LIBCPP_TEMPLATE_VIS time_point
1336{
1337    static_assert(__is_duration<_Duration>::value,
1338                  "Second template parameter of time_point must be a std::chrono::duration");
1339public:
1340    typedef _Clock                    clock;
1341    typedef _Duration                 duration;
1342    typedef typename duration::rep    rep;
1343    typedef typename duration::period period;
1344private:
1345    duration __d_;
1346
1347public:
1348    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 time_point() : __d_(duration::zero()) {}
1349    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 explicit time_point(const duration& __d) : __d_(__d) {}
1350
1351    // conversions
1352    template <class _Duration2>
1353    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
1354    time_point(const time_point<clock, _Duration2>& t,
1355        typename enable_if
1356        <
1357            is_convertible<_Duration2, duration>::value
1358        >::type* = 0)
1359            : __d_(t.time_since_epoch()) {}
1360
1361    // observer
1362
1363    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11 duration time_since_epoch() const {return __d_;}
1364
1365    // arithmetic
1366
1367    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 time_point& operator+=(const duration& __d) {__d_ += __d; return *this;}
1368    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 time_point& operator-=(const duration& __d) {__d_ -= __d; return *this;}
1369
1370    // special values
1371
1372    _LIBCPP_INLINE_VISIBILITY static _LIBCPP_CONSTEXPR time_point min() {return time_point(duration::min());}
1373    _LIBCPP_INLINE_VISIBILITY static _LIBCPP_CONSTEXPR time_point max() {return time_point(duration::max());}
1374};
1375
1376} // chrono
1377
1378template <class _Clock, class _Duration1, class _Duration2>
1379struct _LIBCPP_TEMPLATE_VIS common_type<chrono::time_point<_Clock, _Duration1>,
1380                                         chrono::time_point<_Clock, _Duration2> >
1381{
1382    typedef chrono::time_point<_Clock, typename common_type<_Duration1, _Duration2>::type> type;
1383};
1384
1385namespace chrono {
1386
1387template <class _ToDuration, class _Clock, class _Duration>
1388inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
1389time_point<_Clock, _ToDuration>
1390time_point_cast(const time_point<_Clock, _Duration>& __t)
1391{
1392    return time_point<_Clock, _ToDuration>(_VSTD::chrono::duration_cast<_ToDuration>(__t.time_since_epoch()));
1393}
1394
1395#if _LIBCPP_STD_VER > 14
1396template <class _ToDuration, class _Clock, class _Duration>
1397inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
1398typename enable_if
1399<
1400    __is_duration<_ToDuration>::value,
1401    time_point<_Clock, _ToDuration>
1402>::type
1403floor(const time_point<_Clock, _Duration>& __t)
1404{
1405    return time_point<_Clock, _ToDuration>{floor<_ToDuration>(__t.time_since_epoch())};
1406}
1407
1408template <class _ToDuration, class _Clock, class _Duration>
1409inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
1410typename enable_if
1411<
1412    __is_duration<_ToDuration>::value,
1413    time_point<_Clock, _ToDuration>
1414>::type
1415ceil(const time_point<_Clock, _Duration>& __t)
1416{
1417    return time_point<_Clock, _ToDuration>{ceil<_ToDuration>(__t.time_since_epoch())};
1418}
1419
1420template <class _ToDuration, class _Clock, class _Duration>
1421inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
1422typename enable_if
1423<
1424    __is_duration<_ToDuration>::value,
1425    time_point<_Clock, _ToDuration>
1426>::type
1427round(const time_point<_Clock, _Duration>& __t)
1428{
1429    return time_point<_Clock, _ToDuration>{round<_ToDuration>(__t.time_since_epoch())};
1430}
1431
1432template <class _Rep, class _Period>
1433inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
1434typename enable_if
1435<
1436    numeric_limits<_Rep>::is_signed,
1437    duration<_Rep, _Period>
1438>::type
1439abs(duration<_Rep, _Period> __d)
1440{
1441    return __d >= __d.zero() ? __d : -__d;
1442}
1443#endif
1444
1445// time_point ==
1446
1447template <class _Clock, class _Duration1, class _Duration2>
1448inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
1449bool
1450operator==(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs)
1451{
1452    return __lhs.time_since_epoch() == __rhs.time_since_epoch();
1453}
1454
1455// time_point !=
1456
1457template <class _Clock, class _Duration1, class _Duration2>
1458inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
1459bool
1460operator!=(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs)
1461{
1462    return !(__lhs == __rhs);
1463}
1464
1465// time_point <
1466
1467template <class _Clock, class _Duration1, class _Duration2>
1468inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
1469bool
1470operator<(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs)
1471{
1472    return __lhs.time_since_epoch() < __rhs.time_since_epoch();
1473}
1474
1475// time_point >
1476
1477template <class _Clock, class _Duration1, class _Duration2>
1478inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
1479bool
1480operator>(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs)
1481{
1482    return __rhs < __lhs;
1483}
1484
1485// time_point <=
1486
1487template <class _Clock, class _Duration1, class _Duration2>
1488inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
1489bool
1490operator<=(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs)
1491{
1492    return !(__rhs < __lhs);
1493}
1494
1495// time_point >=
1496
1497template <class _Clock, class _Duration1, class _Duration2>
1498inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
1499bool
1500operator>=(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs)
1501{
1502    return !(__lhs < __rhs);
1503}
1504
1505// time_point operator+(time_point x, duration y);
1506
1507template <class _Clock, class _Duration1, class _Rep2, class _Period2>
1508inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
1509time_point<_Clock, typename common_type<_Duration1, duration<_Rep2, _Period2> >::type>
1510operator+(const time_point<_Clock, _Duration1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
1511{
1512    typedef time_point<_Clock, typename common_type<_Duration1, duration<_Rep2, _Period2> >::type> _Tr;
1513    return _Tr (__lhs.time_since_epoch() + __rhs);
1514}
1515
1516// time_point operator+(duration x, time_point y);
1517
1518template <class _Rep1, class _Period1, class _Clock, class _Duration2>
1519inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
1520time_point<_Clock, typename common_type<duration<_Rep1, _Period1>, _Duration2>::type>
1521operator+(const duration<_Rep1, _Period1>& __lhs, const time_point<_Clock, _Duration2>& __rhs)
1522{
1523    return __rhs + __lhs;
1524}
1525
1526// time_point operator-(time_point x, duration y);
1527
1528template <class _Clock, class _Duration1, class _Rep2, class _Period2>
1529inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
1530time_point<_Clock, typename common_type<_Duration1, duration<_Rep2, _Period2> >::type>
1531operator-(const time_point<_Clock, _Duration1>& __lhs, const duration<_Rep2, _Period2>& __rhs)
1532{
1533    typedef time_point<_Clock, typename common_type<_Duration1, duration<_Rep2, _Period2> >::type> _Ret;
1534    return _Ret(__lhs.time_since_epoch() -__rhs);
1535}
1536
1537// duration operator-(time_point x, time_point y);
1538
1539template <class _Clock, class _Duration1, class _Duration2>
1540inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
1541typename common_type<_Duration1, _Duration2>::type
1542operator-(const time_point<_Clock, _Duration1>& __lhs, const time_point<_Clock, _Duration2>& __rhs)
1543{
1544    return __lhs.time_since_epoch() - __rhs.time_since_epoch();
1545}
1546
1547//////////////////////////////////////////////////////////
1548/////////////////////// clocks ///////////////////////////
1549//////////////////////////////////////////////////////////
1550
1551class _LIBCPP_TYPE_VIS system_clock
1552{
1553public:
1554    typedef microseconds                     duration;
1555    typedef duration::rep                    rep;
1556    typedef duration::period                 period;
1557    typedef chrono::time_point<system_clock> time_point;
1558    static _LIBCPP_CONSTEXPR_AFTER_CXX11 const bool is_steady = false;
1559
1560    static time_point now() _NOEXCEPT;
1561    static time_t     to_time_t  (const time_point& __t) _NOEXCEPT;
1562    static time_point from_time_t(time_t __t) _NOEXCEPT;
1563};
1564
1565#ifndef _LIBCPP_HAS_NO_MONOTONIC_CLOCK
1566class _LIBCPP_TYPE_VIS steady_clock
1567{
1568public:
1569    typedef nanoseconds                                   duration;
1570    typedef duration::rep                                 rep;
1571    typedef duration::period                              period;
1572    typedef chrono::time_point<steady_clock, duration>    time_point;
1573    static _LIBCPP_CONSTEXPR_AFTER_CXX11 const bool is_steady = true;
1574
1575    static time_point now() _NOEXCEPT;
1576};
1577
1578typedef steady_clock high_resolution_clock;
1579#else
1580typedef system_clock high_resolution_clock;
1581#endif
1582
1583#if _LIBCPP_STD_VER > 17
1584
1585struct _LIBCPP_TYPE_VIS last_spec { explicit last_spec() = default; };
1586
1587
1588class _LIBCPP_TYPE_VIS day {
1589private:
1590    unsigned char __d;
1591public:
1592    day() = default;
1593    explicit inline constexpr day(unsigned __val) noexcept : __d(static_cast<unsigned char>(__val)) {}
1594    inline constexpr day& operator++()    noexcept { ++__d; return *this; }
1595    inline constexpr day  operator++(int) noexcept { day __tmp = *this; ++(*this); return __tmp; }
1596    inline constexpr day& operator--()    noexcept { --__d; return *this; }
1597    inline constexpr day  operator--(int) noexcept { day __tmp = *this; --(*this); return __tmp; }
1598           constexpr day& operator+=(const days& __dd) noexcept;
1599           constexpr day& operator-=(const days& __dd) noexcept;
1600    explicit inline constexpr operator unsigned() const noexcept { return __d; }
1601    inline constexpr bool ok() const noexcept { return __d >= 1 && __d <= 31; }
1602  };
1603
1604
1605inline constexpr
1606bool operator==(const day& __lhs, const day& __rhs) noexcept
1607{ return static_cast<unsigned>(__lhs) == static_cast<unsigned>(__rhs); }
1608
1609inline constexpr
1610bool operator!=(const day& __lhs, const day& __rhs) noexcept
1611{ return !(__lhs == __rhs); }
1612
1613inline constexpr
1614bool operator< (const day& __lhs, const day& __rhs) noexcept
1615{ return static_cast<unsigned>(__lhs) <  static_cast<unsigned>(__rhs); }
1616
1617inline constexpr
1618bool operator> (const day& __lhs, const day& __rhs) noexcept
1619{ return __rhs < __lhs; }
1620
1621inline constexpr
1622bool operator<=(const day& __lhs, const day& __rhs) noexcept
1623{ return !(__rhs < __lhs);}
1624
1625inline constexpr
1626bool operator>=(const day& __lhs, const day& __rhs) noexcept
1627{ return !(__lhs < __rhs); }
1628
1629inline constexpr
1630day operator+ (const day& __lhs, const days& __rhs) noexcept
1631{ return day(static_cast<unsigned>(__lhs) + __rhs.count()); }
1632
1633inline constexpr
1634day operator+ (const days& __lhs, const day& __rhs) noexcept
1635{ return __rhs + __lhs; }
1636
1637inline constexpr
1638day operator- (const day& __lhs, const days& __rhs) noexcept
1639{ return __lhs + -__rhs; }
1640
1641inline constexpr
1642days operator-(const day& __lhs, const day& __rhs) noexcept
1643{ return days(static_cast<int>(static_cast<unsigned>(__lhs)) -
1644              static_cast<int>(static_cast<unsigned>(__rhs))); }
1645
1646inline constexpr day& day::operator+=(const days& __dd) noexcept
1647{ *this = *this + __dd; return *this; }
1648
1649inline constexpr day& day::operator-=(const days& __dd) noexcept
1650{ *this = *this - __dd; return *this; }
1651
1652
1653class _LIBCPP_TYPE_VIS month {
1654private:
1655    unsigned char __m;
1656public:
1657    month() = default;
1658    explicit inline constexpr month(unsigned __val) noexcept : __m(static_cast<unsigned char>(__val)) {}
1659    inline constexpr month& operator++()    noexcept { ++__m; return *this; }
1660    inline constexpr month  operator++(int) noexcept { month __tmp = *this; ++(*this); return __tmp; }
1661    inline constexpr month& operator--()    noexcept { --__m; return *this; }
1662    inline constexpr month  operator--(int) noexcept { month __tmp = *this; --(*this); return __tmp; }
1663           constexpr month& operator+=(const months& __m1) noexcept;
1664           constexpr month& operator-=(const months& __m1) noexcept;
1665    explicit inline constexpr operator unsigned() const noexcept { return __m; }
1666    inline constexpr bool ok() const noexcept { return __m >= 1 && __m <= 12; }
1667};
1668
1669
1670inline constexpr
1671bool operator==(const month& __lhs, const month& __rhs) noexcept
1672{ return static_cast<unsigned>(__lhs) == static_cast<unsigned>(__rhs); }
1673
1674inline constexpr
1675bool operator!=(const month& __lhs, const month& __rhs) noexcept
1676{ return !(__lhs == __rhs); }
1677
1678inline constexpr
1679bool operator< (const month& __lhs, const month& __rhs) noexcept
1680{ return static_cast<unsigned>(__lhs)  < static_cast<unsigned>(__rhs); }
1681
1682inline constexpr
1683bool operator> (const month& __lhs, const month& __rhs) noexcept
1684{ return __rhs < __lhs; }
1685
1686inline constexpr
1687bool operator<=(const month& __lhs, const month& __rhs) noexcept
1688{ return !(__rhs < __lhs); }
1689
1690inline constexpr
1691bool operator>=(const month& __lhs, const month& __rhs) noexcept
1692{ return !(__lhs < __rhs); }
1693
1694inline constexpr
1695month operator+ (const month& __lhs, const months& __rhs) noexcept
1696{
1697    auto const __mu = static_cast<long long>(static_cast<unsigned>(__lhs)) + (__rhs.count() - 1);
1698    auto const __yr = (__mu >= 0 ? __mu : __mu - 11) / 12;
1699    return month{static_cast<unsigned>(__mu - __yr * 12 + 1)};
1700}
1701
1702inline constexpr
1703month operator+ (const months& __lhs, const month& __rhs) noexcept
1704{ return __rhs + __lhs; }
1705
1706inline constexpr
1707month operator- (const month& __lhs, const months& __rhs) noexcept
1708{ return __lhs + -__rhs; }
1709
1710inline constexpr
1711months operator-(const month& __lhs, const month& __rhs) noexcept
1712{
1713    auto const __dm = static_cast<unsigned>(__lhs) - static_cast<unsigned>(__rhs);
1714    return months(__dm <= 11 ? __dm : __dm + 12);
1715}
1716
1717inline constexpr month& month::operator+=(const months& __dm) noexcept
1718{ *this = *this + __dm; return *this; }
1719
1720inline constexpr month& month::operator-=(const months& __dm) noexcept
1721{ *this = *this - __dm; return *this; }
1722
1723
1724class _LIBCPP_TYPE_VIS year {
1725private:
1726    short __y;
1727public:
1728    year() = default;
1729    explicit inline constexpr year(int __val) noexcept : __y(static_cast<short>(__val)) {}
1730
1731    inline constexpr year& operator++()    noexcept { ++__y; return *this; };
1732    inline constexpr year  operator++(int) noexcept { year __tmp = *this; ++(*this); return __tmp; };
1733    inline constexpr year& operator--()    noexcept { --__y; return *this; };
1734    inline constexpr year  operator--(int) noexcept { year __tmp = *this; --(*this); return __tmp; };
1735           constexpr year& operator+=(const years& __dy) noexcept;
1736           constexpr year& operator-=(const years& __dy) noexcept;
1737    inline constexpr year operator+() const noexcept { return *this; }
1738    inline constexpr year operator-() const noexcept { return year{-__y}; };
1739
1740    inline constexpr bool is_leap() const noexcept { return __y % 4 == 0 && (__y % 100 != 0 || __y % 400 == 0); }
1741    explicit inline constexpr operator int() const noexcept { return __y; }
1742           constexpr bool ok() const noexcept;
1743    static inline constexpr year min() noexcept { return year{-32767}; }
1744    static inline constexpr year max() noexcept { return year{ 32767}; }
1745};
1746
1747
1748inline constexpr
1749bool operator==(const year& __lhs, const year& __rhs) noexcept
1750{ return static_cast<int>(__lhs) == static_cast<int>(__rhs); }
1751
1752inline constexpr
1753bool operator!=(const year& __lhs, const year& __rhs) noexcept
1754{ return !(__lhs == __rhs); }
1755
1756inline constexpr
1757bool operator< (const year& __lhs, const year& __rhs) noexcept
1758{ return static_cast<int>(__lhs)  < static_cast<int>(__rhs); }
1759
1760inline constexpr
1761bool operator> (const year& __lhs, const year& __rhs) noexcept
1762{ return __rhs < __lhs; }
1763
1764inline constexpr
1765bool operator<=(const year& __lhs, const year& __rhs) noexcept
1766{ return !(__rhs < __lhs); }
1767
1768inline constexpr
1769bool operator>=(const year& __lhs, const year& __rhs) noexcept
1770{ return !(__lhs < __rhs); }
1771
1772inline constexpr
1773year operator+ (const year& __lhs, const years& __rhs) noexcept
1774{ return year(static_cast<int>(__lhs) + __rhs.count()); }
1775
1776inline constexpr
1777year operator+ (const years& __lhs, const year& __rhs) noexcept
1778{ return __rhs + __lhs; }
1779
1780inline constexpr
1781year operator- (const year& __lhs, const years& __rhs) noexcept
1782{ return __lhs + -__rhs; }
1783
1784inline constexpr
1785years operator-(const year& __lhs, const year& __rhs) noexcept
1786{ return years{static_cast<int>(__lhs) - static_cast<int>(__rhs)}; }
1787
1788
1789inline constexpr year& year::operator+=(const years& __dy) noexcept
1790{ *this = *this + __dy; return *this; }
1791
1792inline constexpr year& year::operator-=(const years& __dy) noexcept
1793{ *this = *this - __dy; return *this; }
1794
1795inline constexpr bool year::ok() const noexcept
1796{ return static_cast<int>(min()) <= __y && __y <= static_cast<int>(max()); }
1797
1798class _LIBCPP_TYPE_VIS weekday_indexed;
1799class _LIBCPP_TYPE_VIS weekday_last;
1800
1801class _LIBCPP_TYPE_VIS weekday {
1802private:
1803    unsigned char __wd;
1804public:
1805  weekday() = default;
1806  explicit inline constexpr weekday(unsigned __val) noexcept: __wd(static_cast<unsigned char>(__val)) {}
1807//   inline constexpr weekday(const sys_days& dp) noexcept;
1808//   explicit constexpr weekday(const local_days& dp) noexcept;
1809  inline constexpr weekday& operator++()    noexcept { __wd = (__wd == 6 ? 0 : __wd + 1); return *this; }
1810  inline constexpr weekday  operator++(int) noexcept { weekday __tmp = *this; ++(*this); return __tmp; }
1811  inline constexpr weekday& operator--()    noexcept { __wd = (__wd == 0 ? 6 : __wd - 1); return *this; }
1812  inline constexpr weekday  operator--(int) noexcept { weekday __tmp = *this; --(*this); return __tmp; }
1813         constexpr weekday& operator+=(const days& __dd) noexcept;
1814         constexpr weekday& operator-=(const days& __dd) noexcept;
1815  explicit inline constexpr operator unsigned() const noexcept { return __wd; }
1816  inline constexpr bool ok() const noexcept { return __wd <= 6; }
1817  constexpr weekday_indexed operator[](unsigned __index) const noexcept;
1818  constexpr weekday_last    operator[](last_spec) const noexcept;
1819};
1820
1821inline constexpr
1822bool operator==(const weekday& __lhs, const weekday& __rhs) noexcept
1823{ return static_cast<unsigned>(__lhs) == static_cast<unsigned>(__rhs); }
1824
1825inline constexpr
1826bool operator!=(const weekday& __lhs, const weekday& __rhs) noexcept
1827{ return !(__lhs == __rhs); }
1828
1829inline constexpr
1830bool operator< (const weekday& __lhs, const weekday& __rhs) noexcept
1831{ return static_cast<unsigned>(__lhs) <  static_cast<unsigned>(__rhs); }
1832
1833inline constexpr
1834bool operator> (const weekday& __lhs, const weekday& __rhs) noexcept
1835{ return __rhs < __lhs; }
1836
1837inline constexpr
1838bool operator<=(const weekday& __lhs, const weekday& __rhs) noexcept
1839{ return !(__rhs < __lhs);}
1840
1841inline constexpr
1842bool operator>=(const weekday& __lhs, const weekday& __rhs) noexcept
1843{ return !(__lhs < __rhs); }
1844
1845constexpr weekday operator+(const weekday& __lhs, const days& __rhs) noexcept
1846{
1847    auto const __mu = static_cast<long long>(static_cast<unsigned>(__lhs)) + __rhs.count();
1848    auto const __yr = (__mu >= 0 ? __mu : __mu - 6) / 7;
1849    return weekday{static_cast<unsigned>(__mu - __yr * 7)};
1850}
1851
1852constexpr weekday operator+(const days& __lhs, const weekday& __rhs) noexcept
1853{ return __rhs + __lhs; }
1854
1855constexpr weekday operator-(const weekday& __lhs, const days& __rhs) noexcept
1856{ return __lhs + -__rhs; }
1857
1858constexpr days operator-(const weekday& __lhs, const weekday& __rhs) noexcept
1859{
1860    const int __wdu = static_cast<unsigned>(__lhs) - static_cast<unsigned>(__rhs);
1861    const int __wk = (__wdu >= 0 ? __wdu : __wdu-6) / 7;
1862    return days{__wdu - __wk * 7};
1863}
1864
1865inline constexpr weekday& weekday::operator+=(const days& __dd) noexcept
1866{ *this = *this + __dd; return *this; }
1867
1868inline constexpr weekday& weekday::operator-=(const days& __dd) noexcept
1869{ *this = *this - __dd; return *this; }
1870
1871
1872class _LIBCPP_TYPE_VIS weekday_indexed {
1873private:
1874    _VSTD::chrono::weekday __wd;
1875    unsigned char          __idx;
1876public:
1877    weekday_indexed() = default;
1878    inline constexpr weekday_indexed(const _VSTD::chrono::weekday& __wdval, unsigned __idxval) noexcept
1879        : __wd{__wdval}, __idx(__idxval) {}
1880    inline constexpr _VSTD::chrono::weekday weekday() const noexcept { return __wd; }
1881    inline constexpr unsigned                 index() const noexcept { return __idx; }
1882    inline constexpr bool ok() const noexcept { return __wd.ok() && __idx >= 1 && __idx <= 5; }
1883};
1884
1885inline constexpr
1886bool operator==(const weekday_indexed& __lhs, const weekday_indexed& __rhs) noexcept
1887{ return __lhs.weekday() == __rhs.weekday() && __lhs.index() == __rhs.index(); }
1888
1889inline constexpr
1890bool operator!=(const weekday_indexed& __lhs, const weekday_indexed& __rhs) noexcept
1891{ return !(__lhs == __rhs); }
1892
1893
1894class _LIBCPP_TYPE_VIS weekday_last {
1895private:
1896    _VSTD::chrono::weekday __wd;
1897public:
1898    explicit constexpr weekday_last(const _VSTD::chrono::weekday& __val) noexcept
1899        : __wd{__val} {}
1900    constexpr _VSTD::chrono::weekday weekday() const noexcept { return __wd; }
1901    constexpr bool ok() const noexcept { return __wd.ok(); }
1902};
1903
1904inline constexpr
1905bool operator==(const weekday_last& __lhs, const weekday_last& __rhs) noexcept
1906{ return __lhs.weekday() == __rhs.weekday(); }
1907
1908inline constexpr
1909bool operator!=(const weekday_last& __lhs, const weekday_last& __rhs) noexcept
1910{ return !(__lhs == __rhs); }
1911
1912inline constexpr
1913weekday_indexed weekday::operator[](unsigned __index) const noexcept { return weekday_indexed{*this, __index}; }
1914
1915inline constexpr
1916weekday_last    weekday::operator[](last_spec) const noexcept { return weekday_last{*this}; }
1917
1918
1919inline constexpr last_spec last{};
1920inline constexpr weekday   Sunday{0};
1921inline constexpr weekday   Monday{1};
1922inline constexpr weekday   Tuesday{2};
1923inline constexpr weekday   Wednesday{3};
1924inline constexpr weekday   Thursday{4};
1925inline constexpr weekday   Friday{5};
1926inline constexpr weekday   Saturday{6};
1927
1928inline constexpr month January{1};
1929inline constexpr month February{2};
1930inline constexpr month March{3};
1931inline constexpr month April{4};
1932inline constexpr month May{5};
1933inline constexpr month June{6};
1934inline constexpr month July{7};
1935inline constexpr month August{8};
1936inline constexpr month September{9};
1937inline constexpr month October{10};
1938inline constexpr month November{11};
1939inline constexpr month December{12};
1940
1941
1942class _LIBCPP_TYPE_VIS month_day {
1943private:
1944   chrono::month __m;
1945   chrono::day   __d;
1946public:
1947    month_day() = default;
1948    constexpr month_day(const chrono::month& __mval, const chrono::day& __dval) noexcept
1949        : __m{__mval}, __d{__dval} {}
1950    inline constexpr chrono::month month() const noexcept { return __m; }
1951    inline constexpr chrono::day   day()   const noexcept { return __d; }
1952    constexpr bool ok() const noexcept;
1953};
1954
1955inline constexpr
1956bool month_day::ok() const noexcept
1957{
1958    if (!__m.ok()) return false;
1959    const unsigned __dval = static_cast<unsigned>(__d);
1960    if (__dval < 1 || __dval > 31) return false;
1961    if (__dval <= 29) return true;
1962//  Now we've got either 30 or 31
1963    const unsigned __mval = static_cast<unsigned>(__m);
1964    if (__mval == 2) return false;
1965    if (__mval == 4 || __mval == 6 || __mval == 9 || __mval == 11)
1966        return __dval == 30;
1967    return true;
1968}
1969
1970inline constexpr
1971bool operator==(const month_day& __lhs, const month_day& __rhs) noexcept
1972{ return __lhs.month() == __rhs.month() && __lhs.day() == __rhs.day(); }
1973
1974inline constexpr
1975bool operator!=(const month_day& __lhs, const month_day& __rhs) noexcept
1976{ return !(__lhs == __rhs); }
1977
1978inline constexpr
1979month_day operator/(const month& __lhs, const day& __rhs) noexcept
1980{ return month_day{__lhs, __rhs}; }
1981
1982constexpr
1983month_day operator/(const day& __lhs, const month& __rhs) noexcept
1984{ return __rhs / __lhs; }
1985
1986inline constexpr
1987month_day operator/(const month& __lhs, int __rhs) noexcept
1988{ return __lhs / day(__rhs); }
1989
1990constexpr
1991month_day operator/(int __lhs, const day& __rhs) noexcept
1992{ return month(__lhs) / __rhs; }
1993
1994constexpr
1995month_day operator/(const day& __lhs, int __rhs) noexcept
1996{ return month(__rhs) / __lhs; }
1997
1998
1999inline constexpr
2000bool operator< (const month_day& __lhs, const month_day& __rhs) noexcept
2001{ return __lhs.month() != __rhs.month() ? __lhs.month() < __rhs.month() : __lhs.day() < __rhs.day(); }
2002
2003inline constexpr
2004bool operator> (const month_day& __lhs, const month_day& __rhs) noexcept
2005{ return __rhs < __lhs; }
2006
2007inline constexpr
2008bool operator<=(const month_day& __lhs, const month_day& __rhs) noexcept
2009{ return !(__rhs < __lhs);}
2010
2011inline constexpr
2012bool operator>=(const month_day& __lhs, const month_day& __rhs) noexcept
2013{ return !(__lhs < __rhs); }
2014
2015
2016
2017class _LIBCPP_TYPE_VIS month_day_last {
2018private:
2019    chrono::month __m;
2020public:
2021    explicit constexpr month_day_last(const chrono::month& __val) noexcept
2022        : __m{__val} {}
2023    inline constexpr chrono::month month() const noexcept { return __m; }
2024    inline constexpr bool ok() const noexcept { return __m.ok(); }
2025};
2026
2027inline constexpr
2028bool operator==(const month_day_last& __lhs, const month_day_last& __rhs) noexcept
2029{ return __lhs.month() == __rhs.month(); }
2030
2031inline constexpr
2032bool operator!=(const month_day_last& __lhs, const month_day_last& __rhs) noexcept
2033{ return !(__lhs == __rhs); }
2034
2035inline constexpr
2036bool operator< (const month_day_last& __lhs, const month_day_last& __rhs) noexcept
2037{ return __lhs.month() < __rhs.month(); }
2038
2039inline constexpr
2040bool operator> (const month_day_last& __lhs, const month_day_last& __rhs) noexcept
2041{ return __rhs < __lhs; }
2042
2043inline constexpr
2044bool operator<=(const month_day_last& __lhs, const month_day_last& __rhs) noexcept
2045{ return !(__rhs < __lhs);}
2046
2047inline constexpr
2048bool operator>=(const month_day_last& __lhs, const month_day_last& __rhs) noexcept
2049{ return !(__lhs < __rhs); }
2050
2051inline constexpr
2052month_day_last operator/(const month& __lhs, last_spec) noexcept
2053{ return month_day_last{__lhs}; }
2054
2055inline constexpr
2056month_day_last operator/(last_spec, const month& __rhs) noexcept
2057{ return month_day_last{__rhs}; }
2058
2059inline constexpr
2060month_day_last operator/(int __lhs, last_spec) noexcept
2061{ return month_day_last{month(__lhs)}; }
2062
2063inline constexpr
2064month_day_last operator/(last_spec, int __rhs) noexcept
2065{ return month_day_last{month(__rhs)}; }
2066
2067
2068class _LIBCPP_TYPE_VIS month_weekday {
2069private:
2070    chrono::month __m;
2071    chrono::weekday_indexed __wdi;
2072public:
2073    month_weekday() = default;
2074    constexpr month_weekday(const chrono::month& __mval, const chrono::weekday_indexed& __wdival) noexcept
2075        : __m{__mval}, __wdi{__wdival} {}
2076    inline constexpr chrono::month                     month() const noexcept { return __m; }
2077    inline constexpr chrono::weekday_indexed weekday_indexed() const noexcept { return __wdi; }
2078    inline constexpr bool                                 ok() const noexcept { return __m.ok() && __wdi.ok(); }
2079};
2080
2081inline constexpr
2082bool operator==(const month_weekday& __lhs, const month_weekday& __rhs) noexcept
2083{ return __lhs.month() == __rhs.month() && __lhs.weekday_indexed() == __rhs.weekday_indexed(); }
2084
2085inline constexpr
2086bool operator!=(const month_weekday& __lhs, const month_weekday& __rhs) noexcept
2087{ return !(__lhs == __rhs); }
2088
2089inline constexpr
2090month_weekday operator/(const month& __lhs, const weekday_indexed& __rhs) noexcept
2091{ return month_weekday{__lhs, __rhs}; }
2092
2093inline constexpr
2094month_weekday operator/(int __lhs, const weekday_indexed& __rhs) noexcept
2095{ return month_weekday{month(__lhs), __rhs}; }
2096
2097inline constexpr
2098month_weekday operator/(const weekday_indexed& __lhs, const month& __rhs) noexcept
2099{ return month_weekday{__rhs, __lhs}; }
2100
2101inline constexpr
2102month_weekday operator/(const weekday_indexed& __lhs, int __rhs) noexcept
2103{ return month_weekday{month(__rhs), __lhs}; }
2104
2105
2106class _LIBCPP_TYPE_VIS month_weekday_last {
2107    chrono::month        __m;
2108    chrono::weekday_last __wdl;
2109  public:
2110    constexpr month_weekday_last(const chrono::month& __mval, const chrono::weekday_last& __wdlval) noexcept
2111        : __m{__mval}, __wdl{__wdlval} {}
2112    inline constexpr chrono::month               month() const noexcept { return __m; }
2113    inline constexpr chrono::weekday_last weekday_last() const noexcept { return __wdl; }
2114    inline constexpr bool                           ok() const noexcept { return __m.ok() && __wdl.ok(); }
2115};
2116
2117inline constexpr
2118bool operator==(const month_weekday_last& __lhs, const month_weekday_last& __rhs) noexcept
2119{ return __lhs.month() == __rhs.month() && __lhs.weekday_last() == __rhs.weekday_last(); }
2120
2121inline constexpr
2122bool operator!=(const month_weekday_last& __lhs, const month_weekday_last& __rhs) noexcept
2123{ return !(__lhs == __rhs); }
2124
2125
2126inline constexpr
2127month_weekday_last operator/(const month& __lhs, const weekday_last& __rhs) noexcept
2128{ return month_weekday_last{__lhs, __rhs}; }
2129
2130inline constexpr
2131month_weekday_last operator/(int __lhs, const weekday_last& __rhs) noexcept
2132{ return month_weekday_last{month(__lhs), __rhs}; }
2133
2134inline constexpr
2135month_weekday_last operator/(const weekday_last& __lhs, const month& __rhs) noexcept
2136{ return month_weekday_last{__rhs, __lhs}; }
2137
2138inline constexpr
2139month_weekday_last operator/(const weekday_last& __lhs, int __rhs) noexcept
2140{ return month_weekday_last{month(__rhs), __lhs}; }
2141
2142
2143class _LIBCPP_TYPE_VIS year_month {
2144    chrono::year  __y;
2145    chrono::month __m;
2146public:
2147    year_month() = default;
2148    constexpr year_month(const chrono::year& __yval, const chrono::month& __mval) noexcept
2149        : __y{__yval}, __m{__mval} {}
2150    inline constexpr chrono::year  year()  const noexcept { return __y; }
2151    inline constexpr chrono::month month() const noexcept { return __m; }
2152    inline constexpr year_month& operator+=(const months& __dm) noexcept { this->__m += __dm; return *this; }
2153    inline constexpr year_month& operator-=(const months& __dm) noexcept { this->__m -= __dm; return *this; }
2154    inline constexpr year_month& operator+=(const years& __dy)  noexcept { this->__y += __dy; return *this; }
2155    inline constexpr year_month& operator-=(const years& __dy)  noexcept { this->__y -= __dy; return *this; }
2156    inline constexpr bool ok() const noexcept { return __y.ok() && __m.ok(); }
2157};
2158
2159inline constexpr
2160year_month operator/(const year& __y, const month& __m) noexcept { return year_month{__y, __m}; }
2161
2162inline constexpr
2163year_month operator/(const year& __y, int __m) noexcept { return year_month{__y, month(__m)}; }
2164
2165inline constexpr
2166bool operator==(const year_month& __lhs, const year_month& __rhs) noexcept
2167{ return __lhs.year() == __rhs.year() && __lhs.month() == __rhs.month(); }
2168
2169inline constexpr
2170bool operator!=(const year_month& __lhs, const year_month& __rhs) noexcept
2171{ return !(__lhs == __rhs); }
2172
2173inline constexpr
2174bool operator< (const year_month& __lhs, const year_month& __rhs) noexcept
2175{ return __lhs.year() != __rhs.year() ? __lhs.year() < __rhs.year() : __lhs.month() < __rhs.month(); }
2176
2177inline constexpr
2178bool operator> (const year_month& __lhs, const year_month& __rhs) noexcept
2179{ return __rhs < __lhs; }
2180
2181inline constexpr
2182bool operator<=(const year_month& __lhs, const year_month& __rhs) noexcept
2183{ return !(__rhs < __lhs);}
2184
2185inline constexpr
2186bool operator>=(const year_month& __lhs, const year_month& __rhs) noexcept
2187{ return !(__lhs < __rhs); }
2188
2189constexpr year_month operator+(const year_month& __lhs, const months& __rhs) noexcept
2190{
2191    int __dmi = static_cast<int>(static_cast<unsigned>(__lhs.month())) - 1 + __rhs.count();
2192    const int __dy = (__dmi >= 0 ? __dmi : __dmi-11) / 12;
2193    __dmi = __dmi - __dy * 12 + 1;
2194    return (__lhs.year() + years(__dy)) / month(static_cast<unsigned>(__dmi));
2195}
2196
2197constexpr year_month operator+(const months& __lhs, const year_month& __rhs) noexcept
2198{ return __rhs + __lhs; }
2199
2200constexpr year_month operator+(const year_month& __lhs, const years& __rhs) noexcept
2201{ return (__lhs.year() + __rhs) / __lhs.month(); }
2202
2203constexpr year_month operator+(const years& __lhs, const year_month& __rhs) noexcept
2204{ return __rhs + __lhs; }
2205
2206constexpr months     operator-(const year_month& __lhs, const year_month& __rhs) noexcept
2207{ return (__lhs.year() - __rhs.year()) + months(static_cast<unsigned>(__lhs.month()) - static_cast<unsigned>(__rhs.month())); }
2208
2209constexpr year_month operator-(const year_month& __lhs, const months& __rhs) noexcept
2210{ return __lhs + -__rhs; }
2211
2212constexpr year_month operator-(const year_month& __lhs, const years& __rhs) noexcept
2213{ return __lhs + -__rhs; }
2214
2215
2216class _LIBCPP_TYPE_VIS year_month_day {
2217private:
2218    chrono::year  __y;
2219    chrono::month __m;
2220    chrono::day   __d;
2221public:
2222     year_month_day() = default;
2223     inline constexpr year_month_day(
2224            const chrono::year& __yval, const chrono::month& __mval, const chrono::day& __dval) noexcept
2225            : __y{__yval}, __m{__mval}, __d{__dval} {}
2226//   inline constexpr year_month_day(const year_month_day_last& __ymdl) noexcept;
2227//   inline constexpr year_month_day(const sys_days& dp) noexcept;
2228//   inline explicit constexpr year_month_day(const local_days& dp) noexcept;
2229            constexpr year_month_day& operator+=(const months& __dm) noexcept;
2230            constexpr year_month_day& operator-=(const months& __dm) noexcept;
2231            constexpr year_month_day& operator+=(const years& __dy)  noexcept;
2232            constexpr year_month_day& operator-=(const years& __dy)  noexcept;
2233     inline constexpr chrono::year  year()  const noexcept { return __y; }
2234     inline constexpr chrono::month month() const noexcept { return __m; }
2235     inline constexpr chrono::day   day()   const noexcept  { return __d; }
2236//   inline constexpr operator            sys_days() const noexcept;
2237//   inline explicit constexpr operator local_days() const noexcept;
2238
2239//   TODO: This is not quite correct; requires the calendar bits to do right
2240//   d_ is in the range [1d, (y_/m_/last).day()],
2241     inline constexpr bool ok() const noexcept { return __y.ok() && __m.ok() && __d.ok(); }
2242};
2243
2244inline constexpr
2245bool operator==(const year_month_day& __lhs, const year_month_day& __rhs) noexcept
2246{ return __lhs.year() == __rhs.year() && __lhs.month() == __rhs.month() && __lhs.day() == __rhs.day(); }
2247
2248inline constexpr
2249bool operator!=(const year_month_day& __lhs, const year_month_day& __rhs) noexcept
2250{ return !(__lhs == __rhs); }
2251
2252inline constexpr
2253bool operator< (const year_month_day& __lhs, const year_month_day& __rhs) noexcept
2254{
2255    if (__lhs.year() < __rhs.year()) return true;
2256    if (__lhs.year() > __rhs.year()) return false;
2257    if (__lhs.month() < __rhs.month()) return true;
2258    if (__lhs.month() > __rhs.month()) return false;
2259    return __lhs.day() < __rhs.day();
2260}
2261
2262inline constexpr
2263bool operator> (const year_month_day& __lhs, const year_month_day& __rhs) noexcept
2264{ return __rhs < __lhs; }
2265
2266inline constexpr
2267bool operator<=(const year_month_day& __lhs, const year_month_day& __rhs) noexcept
2268{ return !(__rhs < __lhs);}
2269
2270inline constexpr
2271bool operator>=(const year_month_day& __lhs, const year_month_day& __rhs) noexcept
2272{ return !(__lhs < __rhs); }
2273
2274inline constexpr
2275year_month_day operator/(const year_month& __lhs, const day& __rhs) noexcept
2276{ return year_month_day{__lhs.year(), __lhs.month(), __rhs}; }
2277
2278inline constexpr
2279year_month_day operator/(const year_month& __lhs, int __rhs) noexcept
2280{ return __lhs / day(__rhs); }
2281
2282inline constexpr
2283year_month_day operator/(const year& __lhs, const month_day& __rhs) noexcept
2284{ return __lhs / __rhs.month() / __rhs.day(); }
2285
2286inline constexpr
2287year_month_day operator/(int __lhs, const month_day& __rhs) noexcept
2288{ return year(__lhs) / __rhs; }
2289
2290inline constexpr
2291year_month_day operator/(const month_day& __lhs, const year& __rhs) noexcept
2292{ return __rhs / __lhs; }
2293
2294inline constexpr
2295year_month_day operator/(const month_day& __lhs, int __rhs) noexcept
2296{ return year(__rhs) / __lhs; }
2297
2298
2299inline constexpr
2300year_month_day operator+(const year_month_day& __lhs, const months& __rhs) noexcept
2301{ return (__lhs.year()/__lhs.month() + __rhs)/__lhs.day(); }
2302
2303inline constexpr
2304year_month_day operator+(const months& __lhs, const year_month_day& __rhs) noexcept
2305{ return __rhs + __lhs; }
2306
2307inline constexpr
2308year_month_day operator-(const year_month_day& __lhs, const months& __rhs) noexcept
2309{ return __lhs + -__rhs; }
2310
2311inline constexpr
2312year_month_day operator+(const year_month_day& __lhs, const years& __rhs) noexcept
2313{ return (__lhs.year() + __rhs) / __lhs.month() / __lhs.day(); }
2314
2315inline constexpr
2316year_month_day operator+(const years& __lhs, const year_month_day& __rhs) noexcept
2317{ return __rhs + __lhs; }
2318
2319inline constexpr
2320year_month_day operator-(const year_month_day& __lhs, const years& __rhs) noexcept
2321{ return __lhs + -__rhs; }
2322
2323inline constexpr year_month_day& year_month_day::operator+=(const months& __dm) noexcept { *this = *this + __dm; return *this; }
2324inline constexpr year_month_day& year_month_day::operator-=(const months& __dm) noexcept { *this = *this - __dm; return *this; }
2325inline constexpr year_month_day& year_month_day::operator+=(const years& __dy)  noexcept { *this = *this + __dy; return *this; }
2326inline constexpr year_month_day& year_month_day::operator-=(const years& __dy)  noexcept { *this = *this - __dy; return *this; }
2327
2328class _LIBCPP_TYPE_VIS year_month_day_last {
2329private:
2330    chrono::year           __y;
2331    chrono::month_day_last __mdl;
2332public:
2333     constexpr year_month_day_last(const year& __yval, const month_day_last& __mdlval) noexcept
2334        : __y{__yval}, __mdl{__mdlval} {}
2335
2336     constexpr year_month_day_last& operator+=(const months& __m) noexcept;
2337     constexpr year_month_day_last& operator-=(const months& __m) noexcept;
2338     constexpr year_month_day_last& operator+=(const years& __y)  noexcept;
2339     constexpr year_month_day_last& operator-=(const years& __y)  noexcept;
2340
2341     constexpr chrono::year           year()           const noexcept { return __y; }
2342     constexpr chrono::month          month()          const noexcept { return __mdl.month(); }
2343     constexpr chrono::month_day_last month_day_last() const noexcept { return __mdl; }
2344//   constexpr chrono::day            day()            const noexcept;
2345//   constexpr          operator sys_days()   const noexcept;
2346//   explicit constexpr operator local_days() const noexcept;
2347     constexpr bool ok() const noexcept { return __y.ok() && __mdl.ok(); }
2348};
2349
2350inline constexpr
2351bool operator==(const year_month_day_last& __lhs, const year_month_day_last& __rhs) noexcept
2352{ return __lhs.year() == __rhs.year() && __lhs.month_day_last() == __rhs.month_day_last(); }
2353
2354inline constexpr
2355bool operator!=(const year_month_day_last& __lhs, const year_month_day_last& __rhs) noexcept
2356{ return !(__lhs == __rhs); }
2357
2358inline constexpr
2359bool operator< (const year_month_day_last& __lhs, const year_month_day_last& __rhs) noexcept
2360{
2361    if (__lhs.year() < __rhs.year()) return true;
2362    if (__lhs.year() > __rhs.year()) return false;
2363    return __lhs.month_day_last() < __rhs.month_day_last();
2364}
2365
2366inline constexpr
2367bool operator> (const year_month_day_last& __lhs, const year_month_day_last& __rhs) noexcept
2368{ return __rhs < __lhs; }
2369
2370inline constexpr
2371bool operator<=(const year_month_day_last& __lhs, const year_month_day_last& __rhs) noexcept
2372{ return !(__rhs < __lhs);}
2373
2374inline constexpr
2375bool operator>=(const year_month_day_last& __lhs, const year_month_day_last& __rhs) noexcept
2376{ return !(__lhs < __rhs); }
2377
2378inline constexpr year_month_day_last operator/(const year_month& __lhs, last_spec) noexcept
2379{ return year_month_day_last{__lhs.year(), month_day_last{__lhs.month()}}; }
2380
2381inline constexpr year_month_day_last operator/(const year& __lhs, const month_day_last& __rhs) noexcept
2382{ return year_month_day_last{__lhs, __rhs}; }
2383
2384inline constexpr year_month_day_last operator/(int __lhs, const month_day_last& __rhs) noexcept
2385{ return year_month_day_last{year{__lhs}, __rhs}; }
2386
2387inline constexpr year_month_day_last operator/(const month_day_last& __lhs, const year& __rhs) noexcept
2388{ return __rhs / __lhs; }
2389
2390inline constexpr year_month_day_last operator/(const month_day_last& __lhs, int __rhs) noexcept
2391{ return year{__rhs} / __lhs; }
2392
2393
2394inline constexpr
2395year_month_day_last operator+(const year_month_day_last& __lhs, const months& __rhs) noexcept
2396{ return (__lhs.year() / __lhs.month() + __rhs) / last; }
2397
2398inline constexpr
2399year_month_day_last operator+(const months& __lhs, const year_month_day_last& __rhs) noexcept
2400{ return __rhs + __lhs; }
2401
2402inline constexpr
2403year_month_day_last operator-(const year_month_day_last& __lhs, const months& __rhs) noexcept
2404{ return __lhs + (-__rhs); }
2405
2406inline constexpr
2407year_month_day_last operator+(const year_month_day_last& __lhs, const years& __rhs) noexcept
2408{ return year_month_day_last{__lhs.year() + __rhs, __lhs.month_day_last()}; }
2409
2410inline constexpr
2411year_month_day_last operator+(const years& __lhs, const year_month_day_last& __rhs) noexcept
2412{ return __rhs + __lhs; }
2413
2414inline constexpr
2415year_month_day_last operator-(const year_month_day_last& __lhs, const years& __rhs) noexcept
2416{ return __lhs + (-__rhs); }
2417
2418inline constexpr year_month_day_last& year_month_day_last::operator+=(const months& __dm) noexcept { *this = *this + __dm; return *this; }
2419inline constexpr year_month_day_last& year_month_day_last::operator-=(const months& __dm) noexcept { *this = *this - __dm; return *this; }
2420inline constexpr year_month_day_last& year_month_day_last::operator+=(const years& __dy)  noexcept { *this = *this + __dy; return *this; }
2421inline constexpr year_month_day_last& year_month_day_last::operator-=(const years& __dy)  noexcept { *this = *this - __dy; return *this; }
2422
2423class _LIBCPP_TYPE_VIS year_month_weekday {
2424    chrono::year            __y;
2425    chrono::month           __m;
2426    chrono::weekday_indexed __wdi;
2427public:
2428    year_month_weekday() = default;
2429    constexpr year_month_weekday(const chrono::year& __yval, const chrono::month& __mval,
2430                               const chrono::weekday_indexed& __wdival) noexcept
2431        : __y{__yval}, __m{__mval}, __wdi{__wdival} {}
2432//  constexpr year_month_weekday(const sys_days& dp) noexcept;
2433//  explicit constexpr year_month_weekday(const local_days& dp) noexcept;
2434    constexpr year_month_weekday& operator+=(const months& m) noexcept;
2435    constexpr year_month_weekday& operator-=(const months& m) noexcept;
2436    constexpr year_month_weekday& operator+=(const years& y)  noexcept;
2437    constexpr year_month_weekday& operator-=(const years& y)  noexcept;
2438
2439    inline constexpr chrono::year                       year() const noexcept { return __y; }
2440    inline constexpr chrono::month                     month() const noexcept { return __m; }
2441    inline constexpr chrono::weekday                 weekday() const noexcept { return __wdi.weekday(); }
2442    inline constexpr unsigned                          index() const noexcept { return __wdi.index(); }
2443    inline constexpr chrono::weekday_indexed weekday_indexed() const noexcept { return __wdi; }
2444
2445//  constexpr          operator sys_days()   const noexcept;
2446//  explicit constexpr operator local_days() const noexcept;
2447    inline constexpr bool ok() const noexcept
2448    {
2449        if (!__y.ok() || !__m.ok() || !__wdi.ok()) return false;
2450    //  TODO: make sure it's a valid date
2451        return true;
2452    }
2453};
2454
2455inline constexpr
2456bool operator==(const year_month_weekday& __lhs, const year_month_weekday& __rhs) noexcept
2457{ return __lhs.year() == __rhs.year() && __lhs.month() == __rhs.month() && __lhs.weekday_indexed() == __rhs.weekday_indexed(); }
2458
2459inline constexpr
2460bool operator!=(const year_month_weekday& __lhs, const year_month_weekday& __rhs) noexcept
2461{ return !(__lhs == __rhs); }
2462
2463inline constexpr
2464year_month_weekday operator/(const year_month& __lhs, const weekday_indexed& __rhs) noexcept
2465{ return year_month_weekday{__lhs.year(), __lhs.month(), __rhs}; }
2466
2467inline constexpr
2468year_month_weekday operator/(const year& __lhs, const month_weekday& __rhs) noexcept
2469{ return year_month_weekday{__lhs, __rhs.month(), __rhs.weekday_indexed()}; }
2470
2471inline constexpr
2472year_month_weekday operator/(int __lhs, const month_weekday& __rhs) noexcept
2473{ return year(__lhs) / __rhs; }
2474
2475inline constexpr
2476year_month_weekday operator/(const month_weekday& __lhs, const year& __rhs) noexcept
2477{ return __rhs / __lhs; }
2478
2479inline constexpr
2480year_month_weekday operator/(const month_weekday& __lhs, int __rhs) noexcept
2481{ return year(__rhs) / __lhs; }
2482
2483
2484inline constexpr
2485year_month_weekday operator+(const year_month_weekday& __lhs, const months& __rhs) noexcept
2486{ return (__lhs.year() / __lhs.month() + __rhs) / __lhs.weekday_indexed(); }
2487
2488inline constexpr
2489year_month_weekday operator+(const months& __lhs, const year_month_weekday& __rhs) noexcept
2490{ return __rhs + __lhs; }
2491
2492inline constexpr
2493year_month_weekday operator-(const year_month_weekday& __lhs, const months& __rhs) noexcept
2494{ return __lhs + (-__rhs); }
2495
2496inline constexpr
2497year_month_weekday operator+(const year_month_weekday& __lhs, const years& __rhs) noexcept
2498{ return year_month_weekday{__lhs.year() + __rhs, __lhs.month(), __lhs.weekday_indexed()}; }
2499
2500inline constexpr
2501year_month_weekday operator+(const years& __lhs, const year_month_weekday& __rhs) noexcept
2502{ return __rhs + __lhs; }
2503
2504inline constexpr
2505year_month_weekday operator-(const year_month_weekday& __lhs, const years& __rhs) noexcept
2506{ return __lhs + (-__rhs); }
2507
2508
2509inline constexpr year_month_weekday& year_month_weekday::operator+=(const months& __dm) noexcept { *this = *this + __dm; return *this; }
2510inline constexpr year_month_weekday& year_month_weekday::operator-=(const months& __dm) noexcept { *this = *this - __dm; return *this; }
2511inline constexpr year_month_weekday& year_month_weekday::operator+=(const years& __dy)  noexcept { *this = *this + __dy; return *this; }
2512inline constexpr year_month_weekday& year_month_weekday::operator-=(const years& __dy)  noexcept { *this = *this - __dy; return *this; }
2513
2514class _LIBCPP_TYPE_VIS year_month_weekday_last {
2515private:
2516    chrono::year         __y;
2517    chrono::month        __m;
2518    chrono::weekday_last __wdl;
2519public:
2520    constexpr year_month_weekday_last(const chrono::year& __yval, const chrono::month& __mval,
2521                                      const chrono::weekday_last& __wdlval) noexcept
2522                : __y{__yval}, __m{__mval}, __wdl{__wdlval} {}
2523    constexpr year_month_weekday_last& operator+=(const months& __dm) noexcept;
2524    constexpr year_month_weekday_last& operator-=(const months& __dm) noexcept;
2525    constexpr year_month_weekday_last& operator+=(const years& __dy)  noexcept;
2526    constexpr year_month_weekday_last& operator-=(const years& __dy)  noexcept;
2527
2528    inline constexpr chrono::year                 year() const noexcept { return __y; }
2529    inline constexpr chrono::month               month() const noexcept { return __m; }
2530    inline constexpr chrono::weekday           weekday() const noexcept { return __wdl.weekday(); }
2531    inline constexpr chrono::weekday_last weekday_last() const noexcept { return __wdl; }
2532//  constexpr          operator sys_days()   const noexcept;
2533//  explicit constexpr operator local_days() const noexcept;
2534    inline constexpr bool ok() const noexcept { return __y.ok() && __m.ok() && __wdl.ok(); }
2535};
2536
2537inline constexpr
2538bool operator==(const year_month_weekday_last& __lhs, const year_month_weekday_last& __rhs) noexcept
2539{ return __lhs.year() == __rhs.year() && __lhs.month() == __rhs.month() && __lhs.weekday_last() == __rhs.weekday_last(); }
2540
2541inline constexpr
2542bool operator!=(const year_month_weekday_last& __lhs, const year_month_weekday_last& __rhs) noexcept
2543{ return !(__lhs == __rhs); }
2544
2545
2546inline constexpr
2547year_month_weekday_last operator/(const year_month& __lhs, const weekday_last& __rhs) noexcept
2548{ return year_month_weekday_last{__lhs.year(), __lhs.month(), __rhs}; }
2549
2550inline constexpr
2551year_month_weekday_last operator/(const year& __lhs, const month_weekday_last& __rhs) noexcept
2552{ return year_month_weekday_last{__lhs, __rhs.month(), __rhs.weekday_last()}; }
2553
2554inline constexpr
2555year_month_weekday_last operator/(int __lhs, const month_weekday_last& __rhs) noexcept
2556{ return year(__lhs) / __rhs; }
2557
2558inline constexpr
2559year_month_weekday_last operator/(const month_weekday_last& __lhs, const year& __rhs) noexcept
2560{ return __rhs / __lhs; }
2561
2562inline constexpr
2563year_month_weekday_last operator/(const month_weekday_last& __lhs, int __rhs) noexcept
2564{ return year(__rhs) / __lhs; }
2565
2566
2567inline constexpr
2568year_month_weekday_last operator+(const year_month_weekday_last& __lhs, const months& __rhs) noexcept
2569{ return (__lhs.year() / __lhs.month() + __rhs) / __lhs.weekday_last(); }
2570
2571inline constexpr
2572year_month_weekday_last operator+(const months& __lhs, const year_month_weekday_last& __rhs) noexcept
2573{ return __rhs + __lhs; }
2574
2575inline constexpr
2576year_month_weekday_last operator-(const year_month_weekday_last& __lhs, const months& __rhs) noexcept
2577{ return __lhs + (-__rhs); }
2578
2579inline constexpr
2580year_month_weekday_last operator+(const year_month_weekday_last& __lhs, const years& __rhs) noexcept
2581{ return year_month_weekday_last{__lhs.year() + __rhs, __lhs.month(), __lhs.weekday_last()}; }
2582
2583inline constexpr
2584year_month_weekday_last operator+(const years& __lhs, const year_month_weekday_last& __rhs) noexcept
2585{ return __rhs + __lhs; }
2586
2587inline constexpr
2588year_month_weekday_last operator-(const year_month_weekday_last& __lhs, const years& __rhs) noexcept
2589{ return __lhs + (-__rhs); }
2590
2591inline constexpr year_month_weekday_last& year_month_weekday_last::operator+=(const months& __dm) noexcept { *this = *this + __dm; return *this; }
2592inline constexpr year_month_weekday_last& year_month_weekday_last::operator-=(const months& __dm) noexcept { *this = *this - __dm; return *this; }
2593inline constexpr year_month_weekday_last& year_month_weekday_last::operator+=(const years& __dy)  noexcept { *this = *this + __dy; return *this; }
2594inline constexpr year_month_weekday_last& year_month_weekday_last::operator-=(const years& __dy)  noexcept { *this = *this - __dy; return *this; }
2595
2596#endif // _LIBCPP_STD_VER > 17
2597} // chrono
2598
2599#if _LIBCPP_STD_VER > 11
2600// Suffixes for duration literals [time.duration.literals]
2601inline namespace literals
2602{
2603  inline namespace chrono_literals
2604  {
2605
2606    constexpr chrono::hours operator""h(unsigned long long __h)
2607    {
2608        return chrono::hours(static_cast<chrono::hours::rep>(__h));
2609    }
2610
2611    constexpr chrono::duration<long double, ratio<3600,1>> operator""h(long double __h)
2612    {
2613        return chrono::duration<long double, ratio<3600,1>>(__h);
2614    }
2615
2616
2617    constexpr chrono::minutes operator""min(unsigned long long __m)
2618    {
2619        return chrono::minutes(static_cast<chrono::minutes::rep>(__m));
2620    }
2621
2622    constexpr chrono::duration<long double, ratio<60,1>> operator""min(long double __m)
2623    {
2624        return chrono::duration<long double, ratio<60,1>> (__m);
2625    }
2626
2627
2628    constexpr chrono::seconds operator""s(unsigned long long __s)
2629    {
2630        return chrono::seconds(static_cast<chrono::seconds::rep>(__s));
2631    }
2632
2633    constexpr chrono::duration<long double> operator""s(long double __s)
2634    {
2635        return chrono::duration<long double> (__s);
2636    }
2637
2638
2639    constexpr chrono::milliseconds operator""ms(unsigned long long __ms)
2640    {
2641        return chrono::milliseconds(static_cast<chrono::milliseconds::rep>(__ms));
2642    }
2643
2644    constexpr chrono::duration<long double, milli> operator""ms(long double __ms)
2645    {
2646        return chrono::duration<long double, milli>(__ms);
2647    }
2648
2649
2650    constexpr chrono::microseconds operator""us(unsigned long long __us)
2651    {
2652        return chrono::microseconds(static_cast<chrono::microseconds::rep>(__us));
2653    }
2654
2655    constexpr chrono::duration<long double, micro> operator""us(long double __us)
2656    {
2657        return chrono::duration<long double, micro> (__us);
2658    }
2659
2660
2661    constexpr chrono::nanoseconds operator""ns(unsigned long long __ns)
2662    {
2663        return chrono::nanoseconds(static_cast<chrono::nanoseconds::rep>(__ns));
2664    }
2665
2666    constexpr chrono::duration<long double, nano> operator""ns(long double __ns)
2667    {
2668        return chrono::duration<long double, nano> (__ns);
2669    }
2670
2671#if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_CXX20_CHRONO_LITERALS)
2672    constexpr chrono::day operator ""d(unsigned long long __d) noexcept
2673    {
2674        return chrono::day(static_cast<unsigned>(__d));
2675    }
2676
2677    constexpr chrono::year operator ""y(unsigned long long __y) noexcept
2678    {
2679        return chrono::year(static_cast<int>(__y));
2680    }
2681#endif
2682}}
2683
2684namespace chrono { // hoist the literals into namespace std::chrono
2685   using namespace literals::chrono_literals;
2686}
2687
2688#endif
2689
2690_LIBCPP_END_NAMESPACE_STD
2691
2692_LIBCPP_POP_MACROS
2693
2694#endif  // _LIBCPP_CHRONO
2695