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addBusinessDays: Return a PlainDate ISO string with amount working days added to value.addDate: Return a PlainDate ISO string with amount added according to units.addDateTime: Return a PlainDateTime ISO string with units added to value.addTime: Return a PlainTime ISO string with units added to value.clampDate: Restrict value to the range [min, max].closestDateTo: Return the candidate date nearest to target by calendar distance.cycleDate: Return a PlainDate ISO string with field cycled by amount, wrapping at that field’s own min/max instead of carrying into the next larger field.cycleDateTime: Return a PlainDateTime ISO string with field cycled by amount, wrapping at that field’s own min/max instead of carrying into the next larger field.cycleTime: Return a PlainTime ISO string with field cycled by amount, wrapping at that field’s own min/max instead of carrying into the next larger field (hour 23 +1 wraps to 0, it never changes a date — cycleTime has no date component to carry into in the first place).diffDate: Return the difference between two PlainDate values using the provided unit.diffDateAsDuration: Return the difference between two PlainDate values as an ISO 8601 duration string, bridging to the duration namespace (see parseDuration, normalizeDuration).diffDateTime: Return the difference between two PlainDateTime values in the requested unit.diffDateTimeAsDuration: Return the difference between two PlainDateTime values as an ISO 8601 duration string, bridging to the duration namespace (see parseDuration, normalizeDuration).diffTime: Return the difference between two PlainTime values in the requested unit.endOfDate: Return the end of the specified date unit for a given ISO 8601 date string.endOfDateTime: Return the end of the specified date-time unit for a given ISO 8601 datetime string.endOfQuarterForDate: Return the last day of the quarter for a given ISO date.endOfQuarterForDateTime: Return the end of the quarter for a given ISO datetime.endOfTime: Return the end of the specified time unit for a given ISO 8601 time string.getDayOfYear: Return the ordinal day-of-year (1-based) for value.getDaysInMonth: Return the number of days in the month containing value.getDaysInYear: Return the number of days in the calendar year containing value.getLargestDateDurationUnit: Return the largest DateDurationUnit from the provided array.getLargestDateTimeDurationUnit: Return the largest DateTimeDurationUnit from the provided array.getLargestTimeDurationUnit: Return the largest TimeDurationUnit from the provided array.getLocaleDayOfWeek: Return the locale-relative day-of-week index for value.getLocaleEndOfWeek: Return the end of the week containing value, using locale’s first day of week (e.g. en-US: week ends Saturday, fr-FR: week ends Sunday).getLocaleStartOfWeek: Return the start of the week containing value, using locale’s first day of week (e.g. en-US: Sunday, fr-FR: Monday).getLocaleWeekYear: Return the locale-relative week-numbering year value belongs to, from locale’s first day of week and a minimal-days-in-first-week rule.getQuarterForDate: Return the quarter of the year (1-4) for a given ISO date.getQuarterForDateTime: Return the quarter of the year (1-4) for a given ISO datetime.getWeekNumber: Calculate the week number based on configurable week start day.getWeekOfMonth: Return the 1-based row value falls on within its month’s calendar grid, using locale’s first day of week.getWeeksInLocaleWeekYear: Return the number of weeks (52 or 53) in the locale week-numbering year containing value, from locale’s first day of week and a minimal-days-in-first-week rule.getWeeksInMonth: Return the number of calendar-grid rows (4, 5, or 6) value’s month spans, using locale’s first day of week.getWeeksInYear: Return the number of ISO weeks (52 or 53) in the ISO week-numbering year containing value.getWeekYear: Return the ISO 8601 week-numbering year value belongs to.maxDate: Return the latest (maximum) of the given PlainDate values.maxDateTime: Return the latest (maximum) of the given PlainDateTime values.maxTime: Return the latest (maximum) of the given PlainTime values.minDate: Return the earliest (minimum) of the given PlainDate values.minDateTime: Return the earliest (minimum) of the given PlainDateTime values.minTime: Return the earliest (minimum) of the given PlainTime values.nextWeekday: Return a PlainDate ISO string for the next occurrence of dayOfWeek on or after value.previousWeekday: Return a PlainDate ISO string for the previous occurrence of dayOfWeek on or before value.roundDate: Round an ISO 8601 date string to the specified date unit.roundDateTime: Round an ISO 8601 datetime string to the specified date-time unit.roundTime: Round an ISO 8601 time string to the specified time unit.setDate: Return a PlainDate ISO string with the given fields set on value.setDateTime: Return a PlainDateTime ISO string with the given fields set on value.setTime: Return a PlainTime ISO string with the given fields set on value.sortDates: Sort an array of PlainDate values in ascending or descending order.sortDateTimes: Sort an array of PlainDateTime values in ascending or descending order.sortTimes: Sort an array of PlainTime values in ascending or descending order.startOfDate: Return the start of the specified date unit for a given ISO 8601 date string.startOfDateTime: Return the start of the specified date-time unit for a given ISO 8601 datetime string.startOfQuarterForDate: Return the first day of the quarter for a given ISO date.startOfQuarterForDateTime: Return the start of the quarter for a given ISO datetime.startOfTime: Return the start of the specified time unit for a given ISO 8601 time string.subtractBusinessDays: Return a PlainDate ISO string with amount working days subtracted from value.subtractDate: Return a PlainDate ISO string with units subtracted from value.subtractDateTime: Return a PlainDateTime ISO string with units subtracted from value.subtractTime: Return a PlainTime ISO string with units subtracted from value.weekOfYearForDate: Return the ISO week number for a given ISO 8601 date string.weekOfYearForDateTime: Return the ISO week number for a given ISO 8601 datetime string.
chopDate: Return the PlainTime portion extracted from an ISO PlainDateTime string.chopMilliseconds: Return a string with millisecond precision removed from a PlainDateTime or PlainTime value.chopSeconds: Return an ISO string with second precision removed from a PlainDateTime or PlainTime value.chopTime: Return the PlainDate portion extracted from an ISO PlainDateTime string.
areDatesEqual: Compare two ISO date-like strings for equality, ignoring time components.areDatesEqualBy: Compare two ISO date strings for equality at a given calendar unit.areDateTimesEqual: Return true if two PlainDateTime ISO strings represent the same instant of local date/time components.areDateTimesEqualBy: Compare two ISO datetime strings for equality at a given unit.areTimesEqual: Return true if two PlainTime ISO strings represent the same time components.isAfterDate: Return true if the first ISO PlainDate string represents a date after the second.isAfterDateTime: Return true when value1 is strictly after value2 for PlainDateTime values.isAfterTime: Return true when value1 is strictly after value2 for PlainTime values.isBeforeDate: Return true when value1 is strictly before value2 for PlainDate values.isBeforeDateTime: Return true when value1 is strictly before value2 for PlainDateTime values.isBeforeTime: Return true when value1 is strictly before value2 for PlainTime values.isBetweenDate: Return true when date is between start and end (inclusive by default).isBetweenDateTime: Return true when dateTime is between start and end (inclusive by default).isBetweenTime: Return true when time is between start and end (inclusive by default).isBusinessDay: Return true when value is a working day in calendar.isFuture: Return true when value is strictly after today, per the system clock and system timeZone.isPast: Return true when value is strictly before today, per the system clock and system timeZone.isRelativeDay: Return true when value falls offsetDays days from today, per the system clock and system timeZone.isThisUnit: Return true when value falls in the same unit as today, per the system clock and system timeZone.isWeekend: Return true when value falls on a weekend day for locale.
convertDateToCalendar: Express a PlainDate in a calendar system: the RFC 9557 string Temporal.PlainDate#toString() writes for that date in that calendar.
formatCalendar: Format a plain date-time as a relative day label plus time-of-day, e.g. “Tomorrow at 2:30 PM”.formatDate: Return a localized string for a PlainDate ISO input using Intl options.formatDateRange: Format a plain date range using the Temporal Intl.DateTimeFormat formatRange API.formatDateTime: Return a localized string for a PlainDateTime ISO input using Intl options.formatDateTimeRange: Format a plain datetime range using the Temporal Intl.DateTimeFormat formatRange API.formatDateTimeToParts: Return the locale-formatted parts of a PlainDateTime.formatDateToParts: Return the locale-formatted parts of a PlainDate.formatRelativeDate: Format the relative time between a plain date and a reference date.formatRelativeDateTime: Format the relative time between a plain date-time and a reference date-time.formatRelativeTime: Format the relative time between a plain time and a reference time.formatSqlDateTime: Format a plain ISO 8601 datetime string as a SQL timestamp literal without a time zone — the YYYY-MM-DD HH:MM:SS[.fff] form of standard SQL TIMESTAMP and MySQL/SQLite DATETIME columns.formatTime: Return a localized string for a PlainTime ISO input using Intl options.
getDay: Return the current day of month using the system timeZone.getDayOfWeek: Return the current ISO day of the week as a number in the system timeZone.getHour: Return the current hour using the system timeZone.getMicrosecond: Return the current microsecond using the system timeZone.getMillisecond: Return the current millisecond using the system timeZone.getMinute: Return the current minute using the system timeZone.getMonth: Return the current month using the system timeZone.getNanosecond: Return the current nanosecond using the system timeZone.getNow: Return the current local PlainDateTime as an ISO string using the system timeZone.getNowUnit: Return the requested current unit value using the system timeZone.getSecond: Return the current second using the system timeZone.getToday: Return the current PlainDate as an ISO string in the system timeZone.getWeekOfYear: Get the ISO week number of the current date.getYear: Return the current year as a zero-padded string in the system timeZone.
intervalAbutsDate: Return true when two half-open date intervals [aStart, aEnd) and [bStart, bEnd) are exactly adjacent — one ends where the other starts, so they share nothing and leave no gap.intervalAbutsDateTime: Return true when two half-open datetime intervals [aStart, aEnd) and [bStart, bEnd) are exactly adjacent — one ends where the other starts, so they share nothing and leave no gap.intervalAbutsTime: Return true when two half-open time intervals [aStart, aEnd) and [bStart, bEnd) are exactly adjacent — one ends where the other starts, so they share nothing and leave no gap.intervalContainsDate: Return true when pointOrStart lies in the half-open interval [intervalStart, intervalEnd) (3-arg), or when the inner interval [innerStart, innerEnd) lies within it (4-arg).intervalContainsDateTime: Return true when pointOrStart lies in the half-open interval [intervalStart, intervalEnd) (3-arg), or when the inner interval [innerStart, innerEnd) lies within it (4-arg).intervalContainsTime: Return true when pointOrStart lies in the half-open interval [intervalStart, intervalEnd) (3-arg), or when the inner interval [innerStart, innerEnd) lies within it (4-arg).intervalCountDate: Count how many unit boundaries a date interval crosses.intervalCountDateTime: Count how many unit boundaries a date-time interval crosses.intervalCountTime: Count how many unit boundaries a time interval crosses.intervalDifferenceDate: Return the portion(s) of interval A not covered by interval B.intervalDifferenceDateTime: Return the portion(s) of interval A not covered by interval B.intervalDifferenceTime: Return the portion(s) of interval A not covered by interval B.intervalDivideEquallyDate: Split a date interval into n equal-length sub-intervals.intervalDivideEquallyDateTime: Split a datetime interval into n equal-length sub-intervals.intervalDivideEquallyTime: Split a time interval into n equal-length sub-intervals.intervalEngulfsDate: Return true when the half-open interval B [bStart, bEnd) lies within the half-open interval A [aStart, aEnd) — every day of B is also in A.intervalEngulfsDateTime: Return true when the half-open interval B [bStart, bEnd) lies within the half-open interval A [aStart, aEnd) — every moment of B is also in A.intervalEngulfsTime: Return true when the half-open interval B [bStart, bEnd) lies within the half-open interval A [aStart, aEnd) — every clock time of B is also in A.intervalFromDurationDate: Construct a date interval from a single point plus an ISO 8601 duration, anchored at either end.intervalFromDurationDateTime: Construct a datetime interval from a single point plus an ISO 8601 duration, anchored at either end.intervalFromDurationTime: Construct a time interval from a single point plus an ISO 8601 duration, anchored at either end.intervalIntersectionDate: Return the overlapping span of two date intervals, or null when they do not overlap.intervalIntersectionDateTime: Return the overlapping span of two datetime intervals, or null when they do not overlap.intervalIntersectionTime: Return the overlapping span of two time intervals, or null when they do not overlap.intervalLengthDate: Return the exact length of a date interval in unit, as a real (possibly fractional) number.intervalLengthDateTime: Return the exact length of a datetime interval in unit, as a real (possibly fractional) number.intervalLengthTime: Return the exact length of a time interval in unit, as a real (possibly fractional) number.intervalOverlappingDaysDate: Return how many distinct calendar dates two date intervals share.intervalOverlappingDaysDateTime: Return how many distinct calendar dates two datetime intervals share.intervalsOverlapDate: Return true when the half-open date intervals [aStart, aEnd) and [bStart, bEnd) share at least one day.intervalsOverlapDateTime: Return true when the half-open datetime intervals [aStart, aEnd) and [bStart, bEnd) share at least one moment.intervalsOverlapTime: Return true when the half-open time intervals [aStart, aEnd) and [bStart, bEnd) share at least one clock time.intervalSplitAtDate: Split a date interval at arbitrary points, producing consecutive sub-intervals.intervalSplitAtDateTime: Split a datetime interval at arbitrary points, producing consecutive sub-intervals.intervalSplitAtTime: Split a time interval at arbitrary points, producing consecutive sub-intervals.intervalUnionDate: Return the combined span of two date intervals, or null when they are disjoint.intervalUnionDateTime: Return the combined span of two datetime intervals, or null when they are disjoint.intervalUnionTime: Return the combined span of two time intervals, or null when they are disjoint.intervalXorAllDate: Return the symmetric difference across a list of date intervals — the set of dates covered by an odd number of the input intervals.intervalXorAllDateTime: Return the symmetric difference across a list of datetime intervals — the set of instants covered by an odd number of the input intervals.intervalXorAllTime: Return the symmetric difference across a list of time intervals — the set of clock times covered by an odd number of the input intervals.intervalXorDate: Return the symmetric difference of two date intervals — time covered by exactly one interval.intervalXorDateTime: Return the symmetric difference of two datetime intervals — time covered by exactly one interval.intervalXorTime: Return the symmetric difference of two time intervals — time covered by exactly one interval.isValidDateInterval: Return true if start and end form a valid date interval — both parseable as ISO PlainDate strings and start <= end.isValidDateTimeInterval: Return true if start and end form a valid datetime interval — both parseable as ISO PlainDateTime strings and start <= end.isValidTimeInterval: Return true if start and end form a valid time interval — both parseable as ISO PlainTime strings and start <= end.mergeIntervalsDate: Collapse a list of date intervals into the minimum set of non-overlapping intervals.mergeIntervalsDateTime: Collapse a list of datetime intervals into the minimum set of non-overlapping intervals.mergeIntervalsTime: Collapse a list of time intervals into the minimum set of non-overlapping intervals.splitIntervalByUnitDate: Split a date interval into sub-intervals of amount × unit.splitIntervalByUnitDateTime: Split a date-time interval into sub-intervals of amount × unit.splitIntervalByUnitTime: Split a time interval into sub-intervals of amount × unit.
getLocaleEraNames: Return a locale’s Gregorian era names as [BCE-label, CE-label].getLocaleMeridiems: Return a locale’s AM/PM (day-period) labels as [AM-label, PM-label].getLocaleMonthNames: Return the 12 Gregorian calendar-month names for a locale, in calendar order (January first, December last — not alphabetical).getLocaleWeekdayNames: Return the 7 weekday names for a locale, ordered starting from the locale’s first day of the week.
mapDatesInRange: Return an array of ISO PlainDate strings between startDate and endDate inclusive.mapDaysInMonth: Return an array of ISO PlainDate strings for every day in the given year-month.
isLeapSecond: Return true if the provided ISO 8601 date-time or time string has a second-60 field.isLeapYear: Return true when the given PlainDate falls in a leap year.isValidCalendarDate: Return true if value is a valid GMT PlainDate string: a bare ISO date (“2024-10-03”) or an RFC 9557 calendar-annotated date (“2024-10-03[u-ca=hebrew]”), as Temporal.PlainDate#toString() and convertDateToCalendar write it.isValidDate: Return true if value is a valid ISO PlainDate string.isValidDateCycleField: Return true when field is a valid DateCycleField.isValidDateDurationUnit: Return true when unit is a valid DateDurationUnit.isValidDateRange: Return whether value1 is before value2.isValidDateTime: Return true when value is a valid PlainDateTime string.isValidDateTimeCycleField: Return true when field is a valid DateTimeCycleField (a valid DateCycleField or TimeCycleField).isValidDateTimeDurationUnit: Return true when unit is a valid DateTimeDurationUnit.isValidDateTimeRange: Return true if value1 and value2 form a valid datetime range — both parseable as ISO PlainDateTime strings and value1 before value2.isValidDateTimeUnit: Return true when unit is a valid DateTimeUnit.isValidDateUnit: Return true when unit is a valid DateUnit.isValidIsoDateLike: Return true when the input is a valid PlainDate or PlainDateTime ISO string.isValidSqlDateTime: Return true when value is a real SQL timestamp literal without a time zone: the YYYY-MM-DD HH:MM:SS[.fff] value of a standard SQL TIMESTAMP or a MySQL/SQLite DATETIME column.isValidTime: Return true when value is a valid ISO PlainTime string.isValidTimeCycleField: Return true when field is a valid TimeCycleField.isValidTimeDurationUnit: Return true when unit is a valid TimeDurationUnit.isValidTimeRange: Return true if value1 and value2 form a valid time range — both parseable as ISO PlainTime strings and value1 before value2.isValidTimeUnit: Return true when unit is a valid TimeUnit.