xref: /freebsd/contrib/llvm-project/libcxx/include/chrono (revision 6580f5c38dd5b01aeeaed16b370f1a12423437f0)
1// -*- C++ -*-
2//===----------------------------------------------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP_CHRONO
11#define _LIBCPP_CHRONO
12
13// clang-format off
14
15/*
16    chrono synopsis
17
18#include <compare> // C++20
19
20namespace std
21{
22namespace chrono
23{
24
25template <class ToDuration, class Rep, class Period>
26constexpr
27ToDuration
28duration_cast(const duration<Rep, Period>& fd);
29
30template <class Rep> struct treat_as_floating_point : is_floating_point<Rep> {};
31
32template <class Rep> inline constexpr bool treat_as_floating_point_v
33    = treat_as_floating_point<Rep>::value;                       // C++17
34
35template <class Rep>
36struct duration_values
37{
38public:
39    static constexpr Rep zero(); // noexcept in C++20
40    static constexpr Rep max();  // noexcept in C++20
41    static constexpr Rep min();  // noexcept in C++20
42};
43
44// duration
45
46template <class Rep, class Period = ratio<1>>
47class duration
48{
49    static_assert(!__is_duration<Rep>::value, "A duration representation can not be a duration");
50    static_assert(__is_ratio<Period>::value, "Second template parameter of duration must be a std::ratio");
51    static_assert(Period::num > 0, "duration period must be positive");
52public:
53    typedef Rep rep;
54    typedef typename _Period::type period;
55
56    constexpr duration() = default;
57    template <class Rep2>
58        constexpr explicit duration(const Rep2& r,
59            typename enable_if
60            <
61               is_convertible<Rep2, rep>::value &&
62               (treat_as_floating_point<rep>::value ||
63               !treat_as_floating_point<rep>::value && !treat_as_floating_point<Rep2>::value)
64            >::type* = 0);
65
66    // conversions
67    template <class Rep2, class Period2>
68        constexpr duration(const duration<Rep2, Period2>& d,
69            typename enable_if
70            <
71                treat_as_floating_point<rep>::value ||
72                ratio_divide<Period2, period>::type::den == 1
73            >::type* = 0);
74
75    // observer
76
77    constexpr rep count() const;
78
79    // arithmetic
80
81    constexpr common_type<duration>::type  operator+() const;
82    constexpr common_type<duration>::type  operator-() const;
83    constexpr duration& operator++();    // constexpr in C++17
84    constexpr duration  operator++(int); // constexpr in C++17
85    constexpr duration& operator--();    // constexpr in C++17
86    constexpr duration  operator--(int); // constexpr in C++17
87
88    constexpr duration& operator+=(const duration& d);  // constexpr in C++17
89    constexpr duration& operator-=(const duration& d);  // constexpr in C++17
90
91    duration& operator*=(const rep& rhs);       // constexpr in C++17
92    duration& operator/=(const rep& rhs);       // constexpr in C++17
93    duration& operator%=(const rep& rhs);       // constexpr in C++17
94    duration& operator%=(const duration& rhs);  // constexpr in C++17
95
96    // special values
97
98    static constexpr duration zero(); // noexcept in C++20
99    static constexpr duration min();  // noexcept in C++20
100    static constexpr duration max();  // noexcept in C++20
101};
102
103typedef duration<long long,         nano> nanoseconds;
104typedef duration<long long,        micro> microseconds;
105typedef duration<long long,        milli> milliseconds;
106typedef duration<long long              > seconds;
107typedef duration<     long, ratio<  60> > minutes;
108typedef duration<     long, ratio<3600> > hours;
109
110template <class Clock, class Duration = typename Clock::duration>
111class time_point
112{
113public:
114    typedef Clock                     clock;
115    typedef Duration                  duration;
116    typedef typename duration::rep    rep;
117    typedef typename duration::period period;
118private:
119    duration d_;  // exposition only
120
121public:
122    time_point();  // has value "epoch" // constexpr in C++14
123    explicit time_point(const duration& d);  // same as time_point() + d // constexpr in C++14
124
125    // conversions
126    template <class Duration2>
127       time_point(const time_point<clock, Duration2>& t); // constexpr in C++14
128
129    // observer
130
131    duration time_since_epoch() const; // constexpr in C++14
132
133    // arithmetic
134
135    time_point& operator+=(const duration& d); // constexpr in C++17
136    time_point& operator-=(const duration& d); // constexpr in C++17
137
138    // special values
139
140    static constexpr time_point min();  // noexcept in C++20
141    static constexpr time_point max();  // noexcept in C++20
142};
143
144} // chrono
145
146// common_type traits
147template <class Rep1, class Period1, class Rep2, class Period2>
148  struct common_type<chrono::duration<Rep1, Period1>, chrono::duration<Rep2, Period2>>;
149
150template <class Clock, class Duration1, class Duration2>
151  struct common_type<chrono::time_point<Clock, Duration1>, chrono::time_point<Clock, Duration2>>;
152
153namespace chrono {
154
155// duration arithmetic
156template <class Rep1, class Period1, class Rep2, class Period2>
157  constexpr
158  typename common_type<duration<Rep1, Period1>, duration<Rep2, Period2>>::type
159  operator+(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
160template <class Rep1, class Period1, class Rep2, class Period2>
161  constexpr
162  typename common_type<duration<Rep1, Period1>, duration<Rep2, Period2>>::type
163  operator-(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
164template <class Rep1, class Period, class Rep2>
165  constexpr
166  duration<typename common_type<Rep1, Rep2>::type, Period>
167  operator*(const duration<Rep1, Period>& d, const Rep2& s);
168template <class Rep1, class Period, class Rep2>
169  constexpr
170  duration<typename common_type<Rep1, Rep2>::type, Period>
171  operator*(const Rep1& s, const duration<Rep2, Period>& d);
172template <class Rep1, class Period, class Rep2>
173  constexpr
174  duration<typename common_type<Rep1, Rep2>::type, Period>
175  operator/(const duration<Rep1, Period>& d, const Rep2& s);
176template <class Rep1, class Period1, class Rep2, class Period2>
177  constexpr
178  typename common_type<Rep1, Rep2>::type
179  operator/(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
180
181// duration comparisons
182template <class Rep1, class Period1, class Rep2, class Period2>
183   constexpr
184   bool operator==(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
185template <class Rep1, class Period1, class Rep2, class Period2>
186   constexpr
187   bool operator!=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs); // removed in C++20
188template <class Rep1, class Period1, class Rep2, class Period2>
189   constexpr
190   bool operator< (const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
191template <class Rep1, class Period1, class Rep2, class Period2>
192   constexpr
193   bool operator<=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
194template <class Rep1, class Period1, class Rep2, class Period2>
195   constexpr
196   bool operator> (const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
197template <class Rep1, class Period1, class Rep2, class Period2>
198   constexpr
199   bool operator>=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
200template<class Rep1, class Period1, class Rep2, class Period2>
201  requires three_way_comparable<typename CT::rep>
202  constexpr auto operator<=>(const duration<Rep1, Period1>& lhs,
203                             const duration<Rep2, Period2>& rhs);                           // since C++20
204
205// duration_cast
206template <class ToDuration, class Rep, class Period>
207  ToDuration duration_cast(const duration<Rep, Period>& d);
208
209template <class ToDuration, class Rep, class Period>
210    constexpr ToDuration floor(const duration<Rep, Period>& d);    // C++17
211template <class ToDuration, class Rep, class Period>
212    constexpr ToDuration ceil(const duration<Rep, Period>& d);     // C++17
213template <class ToDuration, class Rep, class Period>
214    constexpr ToDuration round(const duration<Rep, Period>& d);    // C++17
215
216// duration I/O
217template<class charT, class traits, class Rep, class Period>       // C++20
218  basic_ostream<charT, traits>&
219    operator<<(basic_ostream<charT, traits>& os,
220               const duration<Rep, Period>& d);
221
222// time_point arithmetic (all constexpr in C++14)
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 Rep1, class Period1, class Clock, class Duration2>
227  time_point<Clock, typename common_type<duration<Rep1, Period1>, Duration2>::type>
228  operator+(const duration<Rep1, Period1>& lhs, const time_point<Clock, Duration2>& rhs);
229template <class Clock, class Duration1, class Rep2, class Period2>
230  time_point<Clock, typename common_type<Duration1, duration<Rep2, Period2>>::type>
231  operator-(const time_point<Clock, Duration1>& lhs, const duration<Rep2, Period2>& rhs);
232template <class Clock, class Duration1, class Duration2>
233  typename common_type<Duration1, Duration2>::type
234  operator-(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
235
236// time_point comparisons (all constexpr in C++14)
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); // removed in C++20
241template <class Clock, class Duration1, class Duration2>
242   bool operator< (const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
243template <class Clock, class Duration1, class Duration2>
244   bool operator<=(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
245template <class Clock, class Duration1, class Duration2>
246   bool operator> (const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
247template <class Clock, class Duration1, class Duration2>
248   bool operator>=(const time_point<Clock, Duration1>& lhs, const time_point<Clock, Duration2>& rhs);
249template<class Clock, class Duration1,
250         three_way_comparable_with<Duration1> Duration2>
251  constexpr auto operator<=>(const time_point<Clock, Duration1>& lhs,
252                             const time_point<Clock, Duration2>& rhs);                                // since C++20
253
254// time_point_cast (constexpr in C++14)
255
256template <class ToDuration, class Clock, class Duration>
257  time_point<Clock, ToDuration> time_point_cast(const time_point<Clock, Duration>& t);
258
259template <class ToDuration, class Clock, class Duration>
260    constexpr time_point<Clock, ToDuration>
261    floor(const time_point<Clock, Duration>& tp);                  // C++17
262
263template <class ToDuration, class Clock, class Duration>
264    constexpr time_point<Clock, ToDuration>
265    ceil(const time_point<Clock, Duration>& tp);                   // C++17
266
267template <class ToDuration, class Clock, class Duration>
268    constexpr time_point<Clock, ToDuration>
269    round(const time_point<Clock, Duration>& tp);                  // C++17
270
271template <class Rep, class Period>
272    constexpr duration<Rep, Period> abs(duration<Rep, Period> d);  // C++17
273
274// Clocks
275
276class system_clock
277{
278public:
279    typedef microseconds                     duration;
280    typedef duration::rep                    rep;
281    typedef duration::period                 period;
282    typedef chrono::time_point<system_clock> time_point;
283    static const bool is_steady =            false; // constexpr in C++14
284
285    static time_point now() noexcept;
286    static time_t     to_time_t  (const time_point& __t) noexcept;
287    static time_point from_time_t(time_t __t) noexcept;
288};
289
290template <class Duration>
291  using sys_time  = time_point<system_clock, Duration>; // C++20
292using sys_seconds = sys_time<seconds>;                  // C++20
293using sys_days    = sys_time<days>;                     // C++20
294
295template<class charT, class traits, class Duration>     // C++20
296  basic_ostream<charT, traits>&
297    operator<<(basic_ostream<charT, traits>& os, const sys_time<Duration>& tp);
298
299template<class charT, class traits>                    // C++20
300  basic_ostream<charT, traits>&
301    operator<<(basic_ostream<charT, traits>& os, const sys_days& dp);
302
303class file_clock                                        // C++20
304{
305public:
306    typedef see-below                      rep;
307    typedef nano                           period;
308    typedef chrono::duration<rep, period>  duration;
309    typedef chrono::time_point<file_clock> time_point;
310    static constexpr bool is_steady =      false;
311
312    static time_point now() noexcept;
313
314    template<class Duration>
315    static sys_time<see-below> to_sys(const file_time<Duration>&);
316
317    template<class Duration>
318    static file_time<see-below> from_sys(const sys_time<Duration>&);
319};
320
321template<class Duration>
322  using file_time = time_point<file_clock, Duration>;   // C++20
323
324template<class charT, class traits, class Duration>     // C++20
325  basic_ostream<charT, traits>&
326    operator<<(basic_ostream<charT, traits>& os, const file_time<Duration>& tp);
327
328class steady_clock
329{
330public:
331    typedef nanoseconds                                   duration;
332    typedef duration::rep                                 rep;
333    typedef duration::period                              period;
334    typedef chrono::time_point<steady_clock, duration>    time_point;
335    static const bool is_steady =                         true; // constexpr in C++14
336
337    static time_point now() noexcept;
338};
339
340typedef steady_clock high_resolution_clock;
341
342// 25.7.8, local time           // C++20
343struct local_t {};
344template<class Duration>
345  using local_time  = time_point<local_t, Duration>;
346using local_seconds = local_time<seconds>;
347using local_days    = local_time<days>;
348
349template<class charT, class traits, class Duration>     // C++20
350  basic_ostream<charT, traits>&
351    operator<<(basic_ostream<charT, traits>& os, const local_time<Duration>& tp);
352
353// 25.8.2, class last_spec    // C++20
354struct last_spec;
355
356// 25.8.3, class day          // C++20
357
358class day;
359constexpr bool operator==(const day& x, const day& y) noexcept;
360constexpr strong_ordering operator<=>(const day& x, const day& y) noexcept;
361constexpr day  operator+(const day&  x, const days& y) noexcept;
362constexpr day  operator+(const days& x, const day&  y) noexcept;
363constexpr day  operator-(const day&  x, const days& y) noexcept;
364constexpr days operator-(const day&  x, const day&  y) noexcept;
365template<class charT, class traits>
366  basic_ostream<charT, traits>&
367    operator<<(basic_ostream<charT, traits>& os, const day& d);
368
369// 25.8.4, class month    // C++20
370class month;
371constexpr bool operator==(const month& x, const month& y) noexcept;
372constexpr strong_ordering operator<=>(const month& x, const month& y) noexcept;
373
374constexpr month  operator+(const month&  x, const months& y) noexcept;
375constexpr month  operator+(const months& x,  const month& y) noexcept;
376constexpr month  operator-(const month&  x, const months& y) noexcept;
377constexpr months operator-(const month&  x,  const month& y) noexcept;
378template<class charT, class traits>
379  basic_ostream<charT, traits>&
380    operator<<(basic_ostream<charT, traits>& os, const month& m);
381
382// 25.8.5, class year    // C++20
383class year;
384constexpr bool operator==(const year& x, const year& y) noexcept;
385constexpr strong_ordering operator<=>(const year& x, const year& y) noexcept;
386
387constexpr year  operator+(const year&  x, const years& y) noexcept;
388constexpr year  operator+(const years& x, const year&  y) noexcept;
389constexpr year  operator-(const year&  x, const years& y) noexcept;
390constexpr years operator-(const year&  x, const year&  y) noexcept;
391template<class charT, class traits>
392  basic_ostream<charT, traits>&
393    operator<<(basic_ostream<charT, traits>& os, const year& y);
394
395// 25.8.6, class weekday    // C++20
396class weekday;
397
398constexpr bool operator==(const weekday& x, const weekday& y) noexcept;
399constexpr weekday operator+(const weekday& x, const days&    y) noexcept;
400constexpr weekday operator+(const days&    x, const weekday& y) noexcept;
401constexpr weekday operator-(const weekday& x, const days&    y) noexcept;
402constexpr days    operator-(const weekday& x, const weekday& y) noexcept;
403template<class charT, class traits>
404  basic_ostream<charT, traits>&
405    operator<<(basic_ostream<charT, traits>& os, const weekday& wd);
406
407// 25.8.7, class weekday_indexed    // C++20
408
409class weekday_indexed;
410constexpr bool operator==(const weekday_indexed& x, const weekday_indexed& y) noexcept;
411
412template<class charT, class traits>
413  basic_ostream<charT, traits>&
414    operator<<(basic_ostream<charT, traits>& os, const weekday_indexed& wdi);
415
416// 25.8.8, class weekday_last    // C++20
417class weekday_last;
418
419constexpr bool operator==(const weekday_last& x, const weekday_last& y) noexcept;
420
421template<class charT, class traits>
422  basic_ostream<charT, traits>&
423    operator<<(basic_ostream<charT, traits>& os, const weekday_last& wdl);
424
425// 25.8.9, class month_day    // C++20
426class month_day;
427
428constexpr bool operator==(const month_day& x, const month_day& y) noexcept;
429constexpr strong_ordering operator<=>(const month_day& x, const month_day& y) noexcept;
430
431template<class charT, class traits>
432  basic_ostream<charT, traits>&
433    operator<<(basic_ostream<charT, traits>& os, const month_day& md);
434
435// 25.8.10, class month_day_last    // C++20
436class month_day_last;
437
438constexpr bool operator==(const month_day_last& x, const month_day_last& y) noexcept;
439constexpr strong_ordering operator<=>(const month_day_last& x, const month_day_last& y) noexcept;
440
441template<class charT, class traits>
442  basic_ostream<charT, traits>&
443    operator<<(basic_ostream<charT, traits>& os, const month_day_last& mdl);
444
445// 25.8.11, class month_weekday    // C++20
446class month_weekday;
447
448constexpr bool operator==(const month_weekday& x, const month_weekday& y) noexcept;
449
450template<class charT, class traits>
451  basic_ostream<charT, traits>&
452    operator<<(basic_ostream<charT, traits>& os, const month_weekday& mwd);
453
454// 25.8.12, class month_weekday_last    // C++20
455class month_weekday_last;
456
457constexpr bool operator==(const month_weekday_last& x, const month_weekday_last& y) noexcept;
458
459template<class charT, class traits>
460  basic_ostream<charT, traits>&
461    operator<<(basic_ostream<charT, traits>& os, const month_weekday_last& mwdl);
462
463
464// 25.8.13, class year_month    // C++20
465class year_month;
466
467constexpr bool operator==(const year_month& x, const year_month& y) noexcept;
468constexpr strong_ordering operator<=>(const year_month& x, const year_month& y) noexcept;
469
470constexpr year_month operator+(const year_month& ym, const months& dm) noexcept;
471constexpr year_month operator+(const months& dm, const year_month& ym) noexcept;
472constexpr year_month operator-(const year_month& ym, const months& dm) noexcept;
473constexpr months operator-(const year_month& x, const year_month& y) noexcept;
474constexpr year_month operator+(const year_month& ym, const years& dy) noexcept;
475constexpr year_month operator+(const years& dy, const year_month& ym) noexcept;
476constexpr year_month operator-(const year_month& ym, const years& dy) noexcept;
477
478template<class charT, class traits>
479  basic_ostream<charT, traits>&
480    operator<<(basic_ostream<charT, traits>& os, const year_month& ym);
481
482// 25.8.14, class year_month_day class    // C++20
483year_month_day;
484
485constexpr bool operator==(const year_month_day& x, const year_month_day& y) noexcept;
486constexpr strong_ordering operator<=>(const year_month_day& x, const year_month_day& y) noexcept;
487
488constexpr year_month_day operator+(const year_month_day& ymd, const months& dm) noexcept;
489constexpr year_month_day operator+(const months& dm, const year_month_day& ymd) noexcept;
490constexpr year_month_day operator+(const year_month_day& ymd, const years& dy) noexcept;
491constexpr year_month_day operator+(const years& dy, const year_month_day& ymd) noexcept;
492constexpr year_month_day operator-(const year_month_day& ymd, const months& dm) noexcept;
493constexpr year_month_day operator-(const year_month_day& ymd, const years& dy) noexcept;
494
495template<class charT, class traits>
496  basic_ostream<charT, traits>&
497    operator<<(basic_ostream<charT, traits>& os, const year_month_day& ymd);
498
499// 25.8.15, class year_month_day_last    // C++20
500class year_month_day_last;
501
502constexpr bool operator==(const year_month_day_last& x, const year_month_day_last& y) noexcept;
503constexpr strong_ordering operator<=>(const year_month_day_last_day& x, const year_month_day_last_day& y) noexcept;
504
505constexpr year_month_day_last
506  operator+(const year_month_day_last& ymdl, const months& dm) noexcept;
507constexpr year_month_day_last
508  operator+(const months& dm, const year_month_day_last& ymdl) noexcept;
509constexpr year_month_day_last
510  operator+(const year_month_day_last& ymdl, const years& dy) noexcept;
511constexpr year_month_day_last
512  operator+(const years& dy, const year_month_day_last& ymdl) noexcept;
513constexpr year_month_day_last
514  operator-(const year_month_day_last& ymdl, const months& dm) noexcept;
515constexpr year_month_day_last
516  operator-(const year_month_day_last& ymdl, const years& dy) noexcept;
517
518template<class charT, class traits>
519  basic_ostream<charT, traits>&
520    operator<<(basic_ostream<charT, traits>& os, const year_month_day_last& ymdl);
521
522// 25.8.16, class year_month_weekday    // C++20
523class year_month_weekday;
524
525constexpr bool operator==(const year_month_weekday& x,
526                          const year_month_weekday& y) noexcept;
527
528constexpr year_month_weekday
529  operator+(const year_month_weekday& ymwd, const months& dm) noexcept;
530constexpr year_month_weekday
531  operator+(const months& dm, const year_month_weekday& ymwd) noexcept;
532constexpr year_month_weekday
533  operator+(const year_month_weekday& ymwd, const years& dy) noexcept;
534constexpr year_month_weekday
535  operator+(const years& dy, const year_month_weekday& ymwd) noexcept;
536constexpr year_month_weekday
537  operator-(const year_month_weekday& ymwd, const months& dm) noexcept;
538constexpr year_month_weekday
539  operator-(const year_month_weekday& ymwd, const years& dy) noexcept;
540
541template<class charT, class traits>
542  basic_ostream<charT, traits>&
543    operator<<(basic_ostream<charT, traits>& os, const year_month_weekday& ymwd);
544
545// 25.8.17, class year_month_weekday_last    // C++20
546class year_month_weekday_last;
547
548constexpr bool operator==(const year_month_weekday_last& x,
549                          const year_month_weekday_last& y) noexcept;
550constexpr year_month_weekday_last
551  operator+(const year_month_weekday_last& ymwdl, const months& dm) noexcept;
552constexpr year_month_weekday_last
553  operator+(const months& dm, const year_month_weekday_last& ymwdl) noexcept;
554constexpr year_month_weekday_last
555  operator+(const year_month_weekday_last& ymwdl, const years& dy) noexcept;
556constexpr year_month_weekday_last
557  operator+(const years& dy, const year_month_weekday_last& ymwdl) noexcept;
558constexpr year_month_weekday_last
559  operator-(const year_month_weekday_last& ymwdl, const months& dm) noexcept;
560constexpr year_month_weekday_last
561  operator-(const year_month_weekday_last& ymwdl, const years& dy) noexcept;
562
563template<class charT, class traits>
564  basic_ostream<charT, traits>&
565    operator<<(basic_ostream<charT, traits>& os, const year_month_weekday_last& ymwdl);
566
567// 25.8.18, civil calendar conventional syntax operators    // C++20
568constexpr year_month
569  operator/(const year& y, const month& m) noexcept;
570constexpr year_month
571  operator/(const year& y, int m) noexcept;
572constexpr month_day
573  operator/(const month& m, const day& d) noexcept;
574constexpr month_day
575  operator/(const month& m, int d) noexcept;
576constexpr month_day
577  operator/(int m, const day& d) noexcept;
578constexpr month_day
579  operator/(const day& d, const month& m) noexcept;
580constexpr month_day
581  operator/(const day& d, int m) noexcept;
582constexpr month_day_last
583  operator/(const month& m, last_spec) noexcept;
584constexpr month_day_last
585  operator/(int m, last_spec) noexcept;
586constexpr month_day_last
587  operator/(last_spec, const month& m) noexcept;
588constexpr month_day_last
589  operator/(last_spec, int m) noexcept;
590constexpr month_weekday
591  operator/(const month& m, const weekday_indexed& wdi) noexcept;
592constexpr month_weekday
593  operator/(int m, const weekday_indexed& wdi) noexcept;
594constexpr month_weekday
595  operator/(const weekday_indexed& wdi, const month& m) noexcept;
596constexpr month_weekday
597  operator/(const weekday_indexed& wdi, int m) noexcept;
598constexpr month_weekday_last
599  operator/(const month& m, const weekday_last& wdl) noexcept;
600constexpr month_weekday_last
601  operator/(int m, const weekday_last& wdl) noexcept;
602constexpr month_weekday_last
603  operator/(const weekday_last& wdl, const month& m) noexcept;
604constexpr month_weekday_last
605  operator/(const weekday_last& wdl, int m) noexcept;
606constexpr year_month_day
607  operator/(const year_month& ym, const day& d) noexcept;
608constexpr year_month_day
609  operator/(const year_month& ym, int d) noexcept;
610constexpr year_month_day
611  operator/(const year& y, const month_day& md) noexcept;
612constexpr year_month_day
613  operator/(int y, const month_day& md) noexcept;
614constexpr year_month_day
615  operator/(const month_day& md, const year& y) noexcept;
616constexpr year_month_day
617  operator/(const month_day& md, int y) noexcept;
618constexpr year_month_day_last
619  operator/(const year_month& ym, last_spec) noexcept;
620constexpr year_month_day_last
621  operator/(const year& y, const month_day_last& mdl) noexcept;
622constexpr year_month_day_last
623  operator/(int y, const month_day_last& mdl) noexcept;
624constexpr year_month_day_last
625  operator/(const month_day_last& mdl, const year& y) noexcept;
626constexpr year_month_day_last
627  operator/(const month_day_last& mdl, int y) noexcept;
628constexpr year_month_weekday
629  operator/(const year_month& ym, const weekday_indexed& wdi) noexcept;
630constexpr year_month_weekday
631  operator/(const year& y, const month_weekday& mwd) noexcept;
632constexpr year_month_weekday
633  operator/(int y, const month_weekday& mwd) noexcept;
634constexpr year_month_weekday
635  operator/(const month_weekday& mwd, const year& y) noexcept;
636constexpr year_month_weekday
637  operator/(const month_weekday& mwd, int y) noexcept;
638constexpr year_month_weekday_last
639  operator/(const year_month& ym, const weekday_last& wdl) noexcept;
640constexpr year_month_weekday_last
641  operator/(const year& y, const month_weekday_last& mwdl) noexcept;
642constexpr year_month_weekday_last
643  operator/(int y, const month_weekday_last& mwdl) noexcept;
644constexpr year_month_weekday_last
645  operator/(const month_weekday_last& mwdl, const year& y) noexcept;
646constexpr year_month_weekday_last
647  operator/(const month_weekday_last& mwdl, int y) noexcept;
648
649// 26.9, class template hh_mm_ss
650template <class Duration>
651class hh_mm_ss
652{
653    bool            is_neg; // exposition only
654    chrono::hours   h;      // exposition only
655    chrono::minutes m;      // exposition only
656    chrono::seconds s;      // exposition only
657    precision       ss;     // exposition only
658
659public:
660    static unsigned constexpr fractional_width = see below;
661    using precision                            = see below;
662
663    constexpr hh_mm_ss() noexcept : hh_mm_ss{Duration::zero()} {}
664    constexpr explicit hh_mm_ss(Duration d) noexcept;
665
666    constexpr bool is_negative() const noexcept;
667    constexpr chrono::hours hours() const noexcept;
668    constexpr chrono::minutes minutes() const noexcept;
669    constexpr chrono::seconds seconds() const noexcept;
670    constexpr precision subseconds() const noexcept;
671
672    constexpr explicit operator  precision()   const noexcept;
673    constexpr          precision to_duration() const noexcept;
674};
675
676template<class charT, class traits, class Duration>
677  basic_ostream<charT, traits>&
678    operator<<(basic_ostream<charT, traits>& os, const hh_mm_ss<Duration>& hms); // C++20
679
680// 26.10, 12/24 hour functions
681constexpr bool is_am(hours const& h) noexcept;
682constexpr bool is_pm(hours const& h) noexcept;
683constexpr hours make12(const hours& h) noexcept;
684constexpr hours make24(const hours& h, bool is_pm) noexcept;
685
686// [time.zone.db], time zone database
687struct tzdb {                                                                    // C++20
688  string                 version;
689};
690
691class tzdb_list {                                                                // C++20
692public:
693  tzdb_list(const tzdb_list&) = delete;
694  tzdb_list& operator=(const tzdb_list&) = delete;
695
696  // unspecified additional constructors
697
698  class const_iterator;
699
700  const tzdb& front() const noexcept;
701
702  const_iterator erase_after(const_iterator p);
703
704  const_iterator begin() const noexcept;
705  const_iterator end()   const noexcept;
706
707  const_iterator cbegin() const noexcept;
708  const_iterator cend()   const noexcept;
709};
710
711// [time.zone.db.access], time zone database access
712const tzdb& get_tzdb();                                                          // C++20
713tzdb_list& get_tzdb_list();                                                      // C++20
714
715// [time.zone.db.remote], remote time zone database support
716const tzdb& reload_tzdb();                                                       // C++20
717string remote_version();                                                         // C++20
718
719// 25.10.5, class time_zone    // C++20
720enum class choose {earliest, latest};
721class time_zone;
722bool operator==(const time_zone& x, const time_zone& y) noexcept;
723bool operator!=(const time_zone& x, const time_zone& y) noexcept;
724bool operator<(const time_zone& x, const time_zone& y) noexcept;
725bool operator>(const time_zone& x, const time_zone& y) noexcept;
726bool operator<=(const time_zone& x, const time_zone& y) noexcept;
727bool operator>=(const time_zone& x, const time_zone& y) noexcept;
728}  // chrono
729
730namespace std {
731  template<class Duration, class charT>
732    struct formatter<chrono::sys_time<Duration>, charT>;                          // C++20
733  template<class Duration, class charT>
734    struct formatter<chrono::filetime<Duration>, charT>;                          // C++20
735  template<class Duration, class charT>
736    struct formatter<chrono::local_time<Duration>, charT>;                        // C++20
737  template<class Rep, class Period, class charT>
738    struct formatter<chrono::duration<Rep, Period>, charT>;                       // C++20
739  template<class charT> struct formatter<chrono::day, charT>;                     // C++20
740  template<class charT> struct formatter<chrono::month, charT>;                   // C++20
741  template<class charT> struct formatter<chrono::year, charT>;                    // C++20
742  template<class charT> struct formatter<chrono::weekday, charT>;                 // C++20
743  template<class charT> struct formatter<chrono::weekday_indexed, charT>;         // C++20
744  template<class charT> struct formatter<chrono::weekday_last, charT>;            // C++20
745  template<class charT> struct formatter<chrono::month_day, charT>;               // C++20
746  template<class charT> struct formatter<chrono::month_day_last, charT>;          // C++20
747  template<class charT> struct formatter<chrono::month_weekday, charT>;           // C++20
748  template<class charT> struct formatter<chrono::month_weekday_last, charT>;      // C++20
749  template<class charT> struct formatter<chrono::year_month, charT>;              // C++20
750  template<class charT> struct formatter<chrono::year_month_day, charT>;          // C++20
751  template<class charT> struct formatter<chrono::year_month_day_last, charT>;     // C++20
752  template<class charT> struct formatter<chrono::year_month_weekday, charT>;      // C++20
753  template<class charT> struct formatter<chrono::year_month_weekday_last, charT>; // C++20
754  template<class Rep, class Period, class charT>
755    struct formatter<chrono::hh_mm_ss<duration<Rep, Period>>, charT>;             // C++20
756} // namespace std
757
758namespace chrono {
759// calendrical constants
760inline constexpr last_spec                              last{};       // C++20
761inline constexpr chrono::weekday                        Sunday{0};    // C++20
762inline constexpr chrono::weekday                        Monday{1};    // C++20
763inline constexpr chrono::weekday                        Tuesday{2};   // C++20
764inline constexpr chrono::weekday                        Wednesday{3}; // C++20
765inline constexpr chrono::weekday                        Thursday{4};  // C++20
766inline constexpr chrono::weekday                        Friday{5};    // C++20
767inline constexpr chrono::weekday                        Saturday{6};  // C++20
768
769inline constexpr chrono::month                          January{1};   // C++20
770inline constexpr chrono::month                          February{2};  // C++20
771inline constexpr chrono::month                          March{3};     // C++20
772inline constexpr chrono::month                          April{4};     // C++20
773inline constexpr chrono::month                          May{5};       // C++20
774inline constexpr chrono::month                          June{6};      // C++20
775inline constexpr chrono::month                          July{7};      // C++20
776inline constexpr chrono::month                          August{8};    // C++20
777inline constexpr chrono::month                          September{9}; // C++20
778inline constexpr chrono::month                          October{10};  // C++20
779inline constexpr chrono::month                          November{11}; // C++20
780inline constexpr chrono::month                          December{12}; // C++20
781}  // chrono
782
783inline namespace literals {
784  inline namespace chrono_literals {
785constexpr chrono::hours                                 operator ""h(unsigned long long); // C++14
786constexpr chrono::duration<unspecified , ratio<3600,1>> operator ""h(long double); // C++14
787constexpr chrono::minutes                               operator ""min(unsigned long long); // C++14
788constexpr chrono::duration<unspecified , ratio<60,1>>   operator ""min(long double); // C++14
789constexpr chrono::seconds                               operator ""s(unsigned long long); // C++14
790constexpr chrono::duration<unspecified >                operator ""s(long double); // C++14
791constexpr chrono::milliseconds                          operator ""ms(unsigned long long); // C++14
792constexpr chrono::duration<unspecified , milli>         operator ""ms(long double); // C++14
793constexpr chrono::microseconds                          operator ""us(unsigned long long); // C++14
794constexpr chrono::duration<unspecified , micro>         operator ""us(long double); // C++14
795constexpr chrono::nanoseconds                           operator ""ns(unsigned long long); // C++14
796constexpr chrono::duration<unspecified , nano>          operator ""ns(long double); // C++14
797constexpr chrono::day                                   operator ""d(unsigned long long d) noexcept; // C++20
798constexpr chrono::year                                  operator ""y(unsigned long long y) noexcept; // C++20
799}  // chrono_literals
800}  // literals
801
802}  // std
803*/
804
805// clang-format on
806
807#include <__assert> // all public C++ headers provide the assertion handler
808#include <__chrono/calendar.h>
809#include <__chrono/convert_to_timespec.h>
810#include <__chrono/convert_to_tm.h>
811#include <__chrono/day.h>
812#include <__chrono/duration.h>
813#include <__chrono/file_clock.h>
814#include <__chrono/hh_mm_ss.h>
815#include <__chrono/high_resolution_clock.h>
816#include <__chrono/literals.h>
817#include <__chrono/month.h>
818#include <__chrono/month_weekday.h>
819#include <__chrono/monthday.h>
820#include <__chrono/steady_clock.h>
821#include <__chrono/system_clock.h>
822#include <__chrono/time_point.h>
823#include <__chrono/weekday.h>
824#include <__chrono/year.h>
825#include <__chrono/year_month.h>
826#include <__chrono/year_month_day.h>
827#include <__chrono/year_month_weekday.h>
828#include <__config>
829#include <version>
830
831// standard-mandated includes
832
833// [time.syn]
834#include <compare>
835
836#if !defined(_LIBCPP_HAS_NO_LOCALIZATION) && _LIBCPP_STD_VER >= 20
837#  include <__chrono/formatter.h>
838#  include <__chrono/ostream.h>
839#  include <__chrono/parser_std_format_spec.h>
840#  include <__chrono/statically_widen.h>
841#endif
842
843#if !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM) &&                              \
844    !defined(_LIBCPP_HAS_NO_LOCALIZATION)
845#  include <__chrono/tzdb.h>
846#  include <__chrono/tzdb_list.h>
847#endif
848
849#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
850#  pragma GCC system_header
851#endif
852
853#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
854#  include <bit>
855#  include <concepts>
856#  include <cstring>
857#  include <forward_list>
858#  include <string>
859#endif
860
861#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER == 20
862#  include <charconv>
863#endif
864
865#endif // _LIBCPP_CHRONO
866