time

¶Millisecond = 1valuesource

¶Second = 1000valuesource

¶Minute = 60000valuesource

¶Hour = 3600000valuesource

¶Now = fn()source

Now returns the wall clock time in milliseconds since the Unix epoch.

¶Unix = fn()source

Unix returns the wall clock time in whole seconds since the Unix epoch.

¶Mono = fn()source

Mono returns a monotonic timestamp in milliseconds. Only differences between two of these have a meaning.

¶Since = fn(t)source

Since returns the milliseconds elapsed since the monotonic timestamp t.

¶Sleep = fn(ms)source

Sleep pauses the current tau routine for ms milliseconds.

¶Measure = fn(f)source

Measure returns the milliseconds taken by f().

¶Daysvaluesource

¶Monthsvaluesource

¶Date = fn(sec)source

Date returns what the wall clock time sec, in seconds since the Unix epoch, stands for: Year, Month (1 to 12), Day, Hour, Minute, Second, the Weekday with Sunday as 0, and the YearDay starting at 1.

The calendar arithmetic is the one Howard Hinnant wrote for chrono: days are counted from the first of March so that the leap day falls at the end of the year, where it does no harm.

¶DateIn = fn(sec, offset)source

DateIn is Date with a zone: offset is the seconds between that zone and UTC, 3600 for Rome in winter and 7200 in summer. The fields read as the clock on that wall reads, while Unix stays the instant it is.

¶LocalOffset = fn(sec)source

LocalOffset is the offset of the local zone at the instant sec, or right now when sec is null.

¶LocalZone = fn(sec)source

LocalZone is the abbreviation of the local zone at that instant: CET, CEST.

¶Local = fn(sec)source

Local returns the date sec stands for where this machine is.

¶NowLocal = fn()source

Now returns the local date of this instant.

¶FromDate = fn(year, month, day, hour, minute, second)source

FromDate returns the seconds since the epoch of the given UTC date, the way back from Date.

¶FromDateIn = fn(year, month, day, hour, minute, second, offset)source

FromDateIn is FromDate in a zone: the date is read as the clock of that zone reads it, and the instant comes back in UTC.

¶Sunday = 0valuesource

¶Monday = 1valuesource

¶Tuesday = 2valuesource

¶Wednesday = 3valuesource

¶Thursday = 4valuesource

¶Friday = 5valuesource

¶Saturday = 6valuesource

¶ISOWeekday = fn(t)source

ISOWeekday numbers the days from Monday as 1 to Sunday as 7.

¶IsWeekend = fn(t)source

IsWeekend reports whether the date falls on a Saturday or a Sunday.

¶StartOfDay = fn(t)source

StartOfDay returns the instant the day of t begins, in its own zone.

¶StartOfWeek = fn(t, first)source

StartOfWeek returns the instant the week holding t begins, with first saying which day that is: Monday in most of Europe, Sunday elsewhere. With no first, Monday.

¶Week = fn(t, first)source

Week returns the number of the week holding t, counting from the first week that starts on a first day, with the days before it in week 0. It is what a calendar on a wall shows.

¶ISOWeek = fn(t)source

ISOWeek returns the ISO 8601 year and week of t: weeks start on Monday and week 1 is the one holding the 4th of January, so the first days of January can belong to the last week of the year before.

¶IsLeap = fn(y)source

IsLeap reports whether the year has a 29th of February.

¶Format = fn(t, layout)source

Format writes t, a date from Date, in the given layout. The verbs are the ones of strftime, the handful that are worth having:

%Y year      %m month     %d day     %j day of the year
%H hour      %M minute    %S second
%b month name, short      %B month name
%a day name, short        %A day name
%z offset from UTC        %% a per cent sign

With no layout the date is written as RFC 3339: 2006-01-02T15:04:05Z.

¶Parse = fn(s)source

Parse reads a date written as RFC 3339, "2006-01-02T15:04:05Z", and returns the seconds since the epoch. The time part may be left out.

¶String = fn(sec)source

String writes the date of the wall clock time sec as RFC 3339.