std.time.calendar

Monday, 1.

Tuesday, 2.

Wednesday, 3.

Thursday, 4.

Friday, 5.

Saturday, 6.

Sunday, 7.

The date, which panics when it isn't one, like 2026-02-30.

The date that many days after 1970-01-01, or before it for a count below 0. One whose year isn't an Int panics.

The value to start from, like 0 for a number, "" for a String, or an empty collection.

The earliest Date there is.

The latest Date there is.

Today, where the zone is, or the OS's zone.

Today, in the OS's zone.

Whether the year, month, and day are a date.

Whether the year has a Feb 29.

How many days the month has in the year, or 0 for a month that isn't from 1 to 12.

The date ISO 8601 writes, like "2026-10-23", with a sign before a year past 4 digits, or Null.

The date the text writes as the pattern says (see format.fb), or Null. A pattern without the year, or without the month and day or the day of the year, panics.

Its year.

From 1, January's, to 12.

Of the month, from 1.

Its day of the week.

From 1, Jan 1's, to 365, or 366 in a leap year.

Its days since 1970-01-01, below 0 before it.

Whether its year is a leap year.

How many days its month has.

That many days later, or earlier for a count below 0.

That many months later, or earlier, on the same day, or the month's last when it's shorter: Jan 31 plus a month is Feb 28, or 29 in a leap year.

That many years later, or earlier, on the same day, or Feb 28 for Feb 29 in a year that has none.

How many days it is to the other date, below 0 when it's earlier.

The first and last days of its week, from Monday to Sunday, of its month, and of its year. The first Date's week starts before it, and the last's ends after it, so theirs panic.

The last day of its week, a Sunday.

The first day of its month.

The last day of its month.

The first day of its year.

The last day of its year.

It at that time of day.

Its first moment where the zone is: midnight, or when its clocks reach the day, where they skip midnight.

As ISO 8601 writes it, like "2026-10-23".

As the pattern says (see format.fb): Format("EEE d MMM yyyy") is "Fri 23 Oct 2026". A pattern letter of a time or a zone panics.

Whether a comes before b.

The time, which panics when it isn't one: hours from 0 to 23, minutes and seconds from 0 to 59, and nanoseconds from 0 to 999999999.

The time that many nanoseconds after midnight, which panics when it's not on the day.

The time at the start of a day: 00:00.

The time in the middle of a day: 12:00.

The value to start from, like 0 for a number, "" for a String, or an empty collection.

The earliest time of day: 00:00.

The latest time of day: a nanosecond before midnight.

Now, where the zone is, or the OS's zone.

Now, in the OS's zone.

Whether hour, minute, second, and nanosecond are a time of day.

The time ISO 8601 writes, like "12:30", "12:30:15", or "12:30:15.25", or Null.

The time the text writes as the pattern says (see format.fb), or Null. A pattern without the hour panics.

From 0 to 23.

From 0 to 59.

From 0 to 59.

Of the second, from 0 to 999999999.

How many seconds of the day have gone by, from 0 to 86399.

How many nanoseconds of the day have gone by.

a on the clock b later, around midnight as a clock goes: 23:00 plus 2 hours is 01:00.

a on the clock b earlier, around midnight as a clock goes: 01:00 minus 2 hours is 23:00.

How long it is from b to a on the same day, below 0 when a is earlier.

Whether a comes before b.

As ISO 8601 writes it, with seconds, and a fraction only when there is one, like "12:30:00" and "12:30:00.25".

As the pattern says (see format.fb): Format("h:mm a") is "1:30 PM". A pattern letter of a date or a zone panics.

The time of day time on date.

The date and time, which panics when either isn't one.

The value to start from, like 0 for a number, "" for a String, or an empty collection.

The earliest LocalDateTime there is.

The latest LocalDateTime there is.

Now, where the zone is, or the OS's zone.

Now, in the OS's zone.

The date and time ISO 8601 writes, like "2026-10-23T12:30:00", with "T", "t", or a space between them, or Null.

The date and time the text writes as the pattern says (see format.fb), or Null. A pattern without the year, or without the month and day or the day of the year, panics; the time's parts it doesn't have are 0.

Its date.

Its time of day.

Its date's year.

Its date's month, from 1 to 12.

Its date's day of the month, from 1.

Its hour, from 0 to 23.

Its minute, from 0 to 59.

Its second, from 0 to 59.

Its nanosecond of the second.

Its date's day of the week.

Its date's day of the year, from 1.

The same time count days later, or earlier, as Date's AddDays goes.

The same time count months later, or earlier, as Date's AddMonths goes.

The same time count years later, or earlier, as Date's AddYears goes.

Midnight on its day.

It where the zone is. When the zone's clocks show it twice, as they're turned back, or never, as they skip it, the disambiguation says which moment it is (see zone.fb).

b after a, on a clock that's never turned: 23:00 plus 2 hours is 01:00 the next day.

b before a, on a clock that's never turned: 01:00 minus 2 hours is 23:00 the day before.

How long it is from b to a, on a clock that's never turned, which panics past the longest Duration.

Whether a comes before b.

As ISO 8601 writes it, like "2026-10-23T12:30:00".

As the pattern says (see format.fb): Format("yyyy-MM-dd HH:mm") is "2026-10-23 12:30". A pattern letter of a zone panics.