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Diffstat (limited to 'third_party/abseil_cpp/absl/time/internal/cctz/include/cctz/civil_time.h')
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diff --git a/third_party/abseil_cpp/absl/time/internal/cctz/include/cctz/civil_time.h b/third_party/abseil_cpp/absl/time/internal/cctz/include/cctz/civil_time.h deleted file mode 100644 index d47ff86fe4..0000000000 --- a/third_party/abseil_cpp/absl/time/internal/cctz/include/cctz/civil_time.h +++ /dev/null @@ -1,332 +0,0 @@ -// Copyright 2016 Google Inc. All Rights Reserved. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// https://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -#ifndef ABSL_TIME_INTERNAL_CCTZ_CIVIL_TIME_H_ -#define ABSL_TIME_INTERNAL_CCTZ_CIVIL_TIME_H_ - -#include "absl/base/config.h" -#include "absl/time/internal/cctz/include/cctz/civil_time_detail.h" - -namespace absl { -ABSL_NAMESPACE_BEGIN -namespace time_internal { -namespace cctz { - -// The term "civil time" refers to the legally recognized human-scale time -// that is represented by the six fields YYYY-MM-DD hh:mm:ss. Modern-day civil -// time follows the Gregorian Calendar and is a time-zone-independent concept. -// A "date" is perhaps the most common example of a civil time (represented in -// this library as cctz::civil_day). This library provides six classes and a -// handful of functions that help with rounding, iterating, and arithmetic on -// civil times while avoiding complications like daylight-saving time (DST). -// -// The following six classes form the core of this civil-time library: -// -// * civil_second -// * civil_minute -// * civil_hour -// * civil_day -// * civil_month -// * civil_year -// -// Each class is a simple value type with the same interface for construction -// and the same six accessors for each of the civil fields (year, month, day, -// hour, minute, and second, aka YMDHMS). These classes differ only in their -// alignment, which is indicated by the type name and specifies the field on -// which arithmetic operates. -// -// Each class can be constructed by passing up to six optional integer -// arguments representing the YMDHMS fields (in that order) to the -// constructor. Omitted fields are assigned their minimum valid value. Hours, -// minutes, and seconds will be set to 0, month and day will be set to 1, and -// since there is no minimum valid year, it will be set to 1970. So, a -// default-constructed civil-time object will have YMDHMS fields representing -// "1970-01-01 00:00:00". Fields that are out-of-range are normalized (e.g., -// October 32 -> November 1) so that all civil-time objects represent valid -// values. -// -// Each civil-time class is aligned to the civil-time field indicated in the -// class's name after normalization. Alignment is performed by setting all the -// inferior fields to their minimum valid value (as described above). The -// following are examples of how each of the six types would align the fields -// representing November 22, 2015 at 12:34:56 in the afternoon. (Note: the -// string format used here is not important; it's just a shorthand way of -// showing the six YMDHMS fields.) -// -// civil_second 2015-11-22 12:34:56 -// civil_minute 2015-11-22 12:34:00 -// civil_hour 2015-11-22 12:00:00 -// civil_day 2015-11-22 00:00:00 -// civil_month 2015-11-01 00:00:00 -// civil_year 2015-01-01 00:00:00 -// -// Each civil-time type performs arithmetic on the field to which it is -// aligned. This means that adding 1 to a civil_day increments the day field -// (normalizing as necessary), and subtracting 7 from a civil_month operates -// on the month field (normalizing as necessary). All arithmetic produces a -// valid civil time. Difference requires two similarly aligned civil-time -// objects and returns the scalar answer in units of the objects' alignment. -// For example, the difference between two civil_hour objects will give an -// answer in units of civil hours. -// -// In addition to the six civil-time types just described, there are -// a handful of helper functions and algorithms for performing common -// calculations. These are described below. -// -// Note: In C++14 and later, this library is usable in a constexpr context. -// -// CONSTRUCTION: -// -// Each of the civil-time types can be constructed in two ways: by directly -// passing to the constructor up to six (optional) integers representing the -// YMDHMS fields, or by copying the YMDHMS fields from a differently aligned -// civil-time type. -// -// civil_day default_value; // 1970-01-01 00:00:00 -// -// civil_day a(2015, 2, 3); // 2015-02-03 00:00:00 -// civil_day b(2015, 2, 3, 4, 5, 6); // 2015-02-03 00:00:00 -// civil_day c(2015); // 2015-01-01 00:00:00 -// -// civil_second ss(2015, 2, 3, 4, 5, 6); // 2015-02-03 04:05:06 -// civil_minute mm(ss); // 2015-02-03 04:05:00 -// civil_hour hh(mm); // 2015-02-03 04:00:00 -// civil_day d(hh); // 2015-02-03 00:00:00 -// civil_month m(d); // 2015-02-01 00:00:00 -// civil_year y(m); // 2015-01-01 00:00:00 -// -// m = civil_month(y); // 2015-01-01 00:00:00 -// d = civil_day(m); // 2015-01-01 00:00:00 -// hh = civil_hour(d); // 2015-01-01 00:00:00 -// mm = civil_minute(hh); // 2015-01-01 00:00:00 -// ss = civil_second(mm); // 2015-01-01 00:00:00 -// -// ALIGNMENT CONVERSION: -// -// The alignment of a civil-time object cannot change, but the object may be -// used to construct a new object with a different alignment. This is referred -// to as "realigning". When realigning to a type with the same or more -// precision (e.g., civil_day -> civil_second), the conversion may be -// performed implicitly since no information is lost. However, if information -// could be discarded (e.g., civil_second -> civil_day), the conversion must -// be explicit at the call site. -// -// void fun(const civil_day& day); -// -// civil_second cs; -// fun(cs); // Won't compile because data may be discarded -// fun(civil_day(cs)); // OK: explicit conversion -// -// civil_day cd; -// fun(cd); // OK: no conversion needed -// -// civil_month cm; -// fun(cm); // OK: implicit conversion to civil_day -// -// NORMALIZATION: -// -// Integer arguments passed to the constructor may be out-of-range, in which -// case they are normalized to produce a valid civil-time object. This enables -// natural arithmetic on constructor arguments without worrying about the -// field's range. Normalization guarantees that there are no invalid -// civil-time objects. -// -// civil_day d(2016, 10, 32); // Out-of-range day; normalized to 2016-11-01 -// -// Note: If normalization is undesired, you can signal an error by comparing -// the constructor arguments to the normalized values returned by the YMDHMS -// properties. -// -// PROPERTIES: -// -// All civil-time types have accessors for all six of the civil-time fields: -// year, month, day, hour, minute, and second. Recall that fields inferior to -// the type's alignment will be set to their minimum valid value. -// -// civil_day d(2015, 6, 28); -// // d.year() == 2015 -// // d.month() == 6 -// // d.day() == 28 -// // d.hour() == 0 -// // d.minute() == 0 -// // d.second() == 0 -// -// COMPARISON: -// -// Comparison always considers all six YMDHMS fields, regardless of the type's -// alignment. Comparison between differently aligned civil-time types is -// allowed. -// -// civil_day feb_3(2015, 2, 3); // 2015-02-03 00:00:00 -// civil_day mar_4(2015, 3, 4); // 2015-03-04 00:00:00 -// // feb_3 < mar_4 -// // civil_year(feb_3) == civil_year(mar_4) -// -// civil_second feb_3_noon(2015, 2, 3, 12, 0, 0); // 2015-02-03 12:00:00 -// // feb_3 < feb_3_noon -// // feb_3 == civil_day(feb_3_noon) -// -// // Iterates all the days of February 2015. -// for (civil_day d(2015, 2, 1); d < civil_month(2015, 3); ++d) { -// // ... -// } -// -// STREAMING: -// -// Each civil-time type may be sent to an output stream using operator<<(). -// The output format follows the pattern "YYYY-MM-DDThh:mm:ss" where fields -// inferior to the type's alignment are omitted. -// -// civil_second cs(2015, 2, 3, 4, 5, 6); -// std::cout << cs << "\n"; // Outputs: 2015-02-03T04:05:06 -// -// civil_day cd(cs); -// std::cout << cd << "\n"; // Outputs: 2015-02-03 -// -// civil_year cy(cs); -// std::cout << cy << "\n"; // Outputs: 2015 -// -// ARITHMETIC: -// -// Civil-time types support natural arithmetic operators such as addition, -// subtraction, and difference. Arithmetic operates on the civil-time field -// indicated in the type's name. Difference requires arguments with the same -// alignment and returns the answer in units of the alignment. -// -// civil_day a(2015, 2, 3); -// ++a; // 2015-02-04 00:00:00 -// --a; // 2015-02-03 00:00:00 -// civil_day b = a + 1; // 2015-02-04 00:00:00 -// civil_day c = 1 + b; // 2015-02-05 00:00:00 -// int n = c - a; // n = 2 (civil days) -// int m = c - civil_month(c); // Won't compile: different types. -// -// EXAMPLE: Adding a month to January 31. -// -// One of the classic questions that arises when considering a civil-time -// library (or a date library or a date/time library) is this: "What happens -// when you add a month to January 31?" This is an interesting question -// because there could be a number of possible answers: -// -// 1. March 3 (or 2 if a leap year). This may make sense if the operation -// wants the equivalent of February 31. -// 2. February 28 (or 29 if a leap year). This may make sense if the operation -// wants the last day of January to go to the last day of February. -// 3. Error. The caller may get some error, an exception, an invalid date -// object, or maybe false is returned. This may make sense because there is -// no single unambiguously correct answer to the question. -// -// Practically speaking, any answer that is not what the programmer intended -// is the wrong answer. -// -// This civil-time library avoids the problem by making it impossible to ask -// ambiguous questions. All civil-time objects are aligned to a particular -// civil-field boundary (such as aligned to a year, month, day, hour, minute, -// or second), and arithmetic operates on the field to which the object is -// aligned. This means that in order to "add a month" the object must first be -// aligned to a month boundary, which is equivalent to the first day of that -// month. -// -// Of course, there are ways to compute an answer the question at hand using -// this civil-time library, but they require the programmer to be explicit -// about the answer they expect. To illustrate, let's see how to compute all -// three of the above possible answers to the question of "Jan 31 plus 1 -// month": -// -// const civil_day d(2015, 1, 31); -// -// // Answer 1: -// // Add 1 to the month field in the constructor, and rely on normalization. -// const auto ans_normalized = civil_day(d.year(), d.month() + 1, d.day()); -// // ans_normalized == 2015-03-03 (aka Feb 31) -// -// // Answer 2: -// // Add 1 to month field, capping to the end of next month. -// const auto next_month = civil_month(d) + 1; -// const auto last_day_of_next_month = civil_day(next_month + 1) - 1; -// const auto ans_capped = std::min(ans_normalized, last_day_of_next_month); -// // ans_capped == 2015-02-28 -// -// // Answer 3: -// // Signal an error if the normalized answer is not in next month. -// if (civil_month(ans_normalized) != next_month) { -// // error, month overflow -// } -// -using civil_year = detail::civil_year; -using civil_month = detail::civil_month; -using civil_day = detail::civil_day; -using civil_hour = detail::civil_hour; -using civil_minute = detail::civil_minute; -using civil_second = detail::civil_second; - -// An enum class with members monday, tuesday, wednesday, thursday, friday, -// saturday, and sunday. These enum values may be sent to an output stream -// using operator<<(). The result is the full weekday name in English with a -// leading capital letter. -// -// weekday wd = weekday::thursday; -// std::cout << wd << "\n"; // Outputs: Thursday -// -using detail::weekday; - -// Returns the weekday for the given civil-time value. -// -// civil_day a(2015, 8, 13); -// weekday wd = get_weekday(a); // wd == weekday::thursday -// -using detail::get_weekday; - -// Returns the civil_day that strictly follows or precedes the given -// civil_day, and that falls on the given weekday. -// -// For example, given: -// -// August 2015 -// Su Mo Tu We Th Fr Sa -// 1 -// 2 3 4 5 6 7 8 -// 9 10 11 12 13 14 15 -// 16 17 18 19 20 21 22 -// 23 24 25 26 27 28 29 -// 30 31 -// -// civil_day a(2015, 8, 13); // get_weekday(a) == weekday::thursday -// civil_day b = next_weekday(a, weekday::thursday); // b = 2015-08-20 -// civil_day c = prev_weekday(a, weekday::thursday); // c = 2015-08-06 -// -// civil_day d = ... -// // Gets the following Thursday if d is not already Thursday -// civil_day thurs1 = next_weekday(d - 1, weekday::thursday); -// // Gets the previous Thursday if d is not already Thursday -// civil_day thurs2 = prev_weekday(d + 1, weekday::thursday); -// -using detail::next_weekday; -using detail::prev_weekday; - -// Returns the day-of-year for the given civil-time value. -// -// civil_day a(2015, 1, 1); -// int yd_jan_1 = get_yearday(a); // yd_jan_1 = 1 -// civil_day b(2015, 12, 31); -// int yd_dec_31 = get_yearday(b); // yd_dec_31 = 365 -// -using detail::get_yearday; - -} // namespace cctz -} // namespace time_internal -ABSL_NAMESPACE_END -} // namespace absl - -#endif // ABSL_TIME_INTERNAL_CCTZ_CIVIL_TIME_H_ |