A Date
is an immutable object identifying a day in the Gregorian calendar.
Date
objects support addition and subtraction of integers, where an integer is interpreted as the number of days. You can compare Date
objects with the numeric comparison operators ==, <, <=, >, >=, !=
. Their stringification in YYYY-MM-DD
format means that comparing them with the string operators eq, lt, le
etc. also gives the right result.
Date.today
creates an object the current day according to the system clock.
my = Date.new(2015, 12, 24); # Christmas Eve!say ; # OUTPUT: «2015-12-24»say .year; # OUTPUT: «2015»say .month; # OUTPUT: «12»say .day; # OUTPUT: «24»say .day-of-week; # OUTPUT: «4» (Thursday)say .later(days => 20); # OUTPUT: «2016-01-13»my = Date.new('2015-12-31'); # New Year's Evesay - ; # OUTPUT: «7», 7 days between New Years/Christmas Evesay + 1; # OUTPUT: «2016-01-01»
Note since version 6.d, .raku can be called on Date
. It will also reject synthetic numerics such as 7̈ .
Methods§
method new§
multi method new(, , , : --> Date)multi method new(:!, : = 1, : = 1 --> Date)multi method new(Str --> Date)multi method new(Instant --> Date)multi method new(DateTime --> Date)
Creates a new Date
object, either from a triple of (year, month, day) that can be coerced to integers, or from a string of the form YYYY-MM-DD
(ISO 8601), or from an Instant or DateTime object. Optionally accepts a formatter as a named parameter.
my = Date.new(2042, 1, 1);= Date.new(year => 2042, month => 1, day => 1);= Date.new("2042-01-01");= Date.new(Instant.from-posix: 1482155532);= Date.new(DateTime.now);
Since Rakudo 2022.03, the "day" argument can also be a callable, with *
representing the last day in a month, and the possibility of getting to the day counting from the last one:
say Date.new(2042, 2, *); # OUTPUT: «2042-02-28»say Date.new(2044, 2, *); # OUTPUT: «2044-02-29»
method new-from-daycount§
method new-from-daycount(,: --> Date)
Creates a new Date
object given $daycount
which is the number of days from epoch Nov. 17, 1858, i.e. the Modified Julian Day. Optionally accepts a formatter as a named parameter.
say Date.new-from-daycount(49987); # OUTPUT: «1995-09-27»
method daycount§
method daycount(Date: --> Int)
Returns the number of days from epoch Nov. 17, 1858, i.e. the Modified Julian Day.
method last-date-in-month§
method last-date-in-month(Date: --> Date)
Returns the last date in the month of the Date
object. Otherwise, returns the invocant if the day value is already the last day of the month.
say Date.new('2015-11-24').last-date-in-month; # OUTPUT: «2015-11-30»
This should allow for much easier ranges like
.. .last-date-in-month
for all remaining dates in the month.
method first-date-in-month§
method first-date-in-month(Date: --> Date)
Returns the first date in the month of the Date
object. Otherwise, returns the invocant if the day value is already the first day of the month.
say Date.new('2015-11-24').first-date-in-month; # OUTPUT: «2015-11-01»
method clone§
method clone(Date: :, :, :, :)
Creates a new Date
object based on the invocant, but with the given arguments overriding the values from the invocant.
say Date.new('2015-11-24').clone(month => 12); # OUTPUT: «2015-12-24»
method today§
method today(: --> Date)
Returns a Date
object for the current day. Optionally accepts a formatter named parameter.
say Date.today;
method truncated-to§
method truncated-to(Date: Cool )
Returns a Date
truncated to the first day of its year, month or week. For example
my = Date.new('2012-12-24');say .truncated-to('year'); # OUTPUT: «2012-01-01»say .truncated-to('month'); # OUTPUT: «2012-12-01»say .truncated-to('week'); # OUTPUT: «2012-12-24», because it's Monday already
method succ§
method succ(Date: --> Date)
Returns a Date
of the following day. "succ" is short for "successor".
say Date.new("2016-02-28").succ; # OUTPUT: «2016-02-29»
method pred§
method pred(Date: --> Date)
Returns a Date
of the previous day. "pred" is short for "predecessor".
say Date.new("2016-01-01").pred; # OUTPUT: «2015-12-31»
method Str§
multi method Str(Date: --> Str)
Returns a string representation of the invocant, as specified by the formatter. If no formatter was specified, an (ISO 8601) date will be returned.
say Date.new('2015-12-24').Str; # OUTPUT: «2015-12-24»my = ;say Date.new('2015-12-24', formatter => ).Str; # OUTPUT: «12/24/2015»
method gist§
multi method gist(Date: --> Str)
Returns the date in YYYY-MM-DD
format (ISO 8601)
say Date.new('2015-12-24').gist; # OUTPUT: «2015-12-24»
method Date§
method Date(--> Date)
Returns the invocant.
say Date.new('2015-12-24').Date; # OUTPUT: «2015-12-24»say Date.Date; # OUTPUT: «(Date)»
method DateTime§
multi method DateTime(Date: --> DateTime)multi method DateTime(Date: --> DateTime)
Converts the invocant to DateTime
say Date.new('2015-12-24').DateTime; # OUTPUT: «2015-12-24T00:00:00Z»say Date.DateTime; # OUTPUT: «(DateTime)»
method Int§
multi method Int(Date: --> Int)
Converts the invocant to Int
. The same value can be obtained with the daycount
method.
Available as of release 2023.02 of the Rakudo compiler.
method Real§
multi method Real(Date: --> Int)
Converts the invocant to Int
. The same value can be obtained with the daycount
method.
Available as of release 2023.02 of the Rakudo compiler.
method Numeric§
multi method Numeric(Date: --> Int)
Converts the invocant to Int
. The same value can be obtained with the daycount
method. This allows Date
objects to be used directly in arithmetic operations.
Available as of release 2023.02 of the Rakudo compiler.
Functions§
sub sleep§
sub sleep( = Inf --> Nil)
Attempt to sleep for the given number of $seconds
. Returns Nil
on completion. Accepts Int
, Num
, Rat
, or Duration
types as an argument since all of these also do Real
.
sleep 5; # Intsleep 5.2; # Numsleep (5/2); # Ratsleep (now - now + 5); # Duration
It is thus possible to sleep for a non-integer amount of time. For instance, the following code shows that sleep (5/2)
sleeps for 2.5 seconds and sleep 5.2
sleeps for 5.2 seconds:
my = now;sleep (5/2);my = now;say -; # OUTPUT: «2.502411561»= now;sleep 5.2;= now;say -; # OUTPUT: «5.20156987»
sub sleep-timer§
sub sleep-timer(Real() = Inf --> Duration)
This function is implemented like sleep
, but unlike the former it does return a Duration
instance with the number of seconds the system did not sleep.
In particular, the returned Duration
will handle the number of seconds remaining when the process has been awakened by some external event (e.g., Virtual Machine or Operating System events). Under normal condition, when sleep is not interrupted, the returned Duration
has a value of 0
, meaning no extra seconds remained to sleep. Therefore, in normal situations:
say sleep-timer 3.14; # OUTPUT: «0»
The same result applies to edge cases, when a negative or zero time to sleep is passed as argument:
say sleep-timer -2; # OUTPUT: 0say sleep-timer 0; # OUTPUT: 0
See also sleep-until.
sub sleep-until§
sub sleep-until(Instant --> Bool)
Works similar to sleep
but checks the current time and keeps sleeping until the required instant in the future has been reached. It uses internally the sleep-timer
method in a loop to ensure that, if accidentally woken up early, it will wait again for the specified amount of time remaining to reach the specified instant. goes back to sleep
Returns True
if the Instant
in the future has been achieved (either by mean of sleeping or because it is right now), False
in the case an Instant
in the past has been specified.
To sleep until 10 seconds into the future, one could write something like this:
say sleep-until now+10; # OUTPUT: «True»
Trying to sleep until a time in the past doesn't work:
my = now - 5;say sleep-until ; # OUTPUT: «False»
However if we put the instant sufficiently far in the future, the sleep should run:
my = now + 30;# assuming the two commands are run within 30 seconds of one another...say sleep-until ; # OUTPUT: «True»
To specify an exact instant in the future, first create a DateTime
at the appropriate point in time, and cast to an Instant
.
my = DateTime.new(year => 2023,month => 9,day => 1,hour => 22,minute => 5);say sleep-until .Instant; # OUTPUT: «True» (eventually...)
This could be used as a primitive kind of alarm clock. For instance, say you need to get up at 7am on the 4th of September 2015, but for some reason your usual alarm clock is broken and you only have your laptop. You can specify the time to get up (being careful about time zones, since DateTime.new
uses UTC by default) as an Instant
and pass this to sleep-until
, after which you can play an mp3 file to wake you up instead of your normal alarm clock. This scenario looks roughly like this:
# DateTime.new uses UTC by default, so get time zone from current timemy = DateTime.now.timezone;my = DateTime.new(year => 2015,month => 9,day => 4,hour => 7,minute => 0,timezone =>).Instant;sleep-until ;;
sub infix:<->§
multi infix:<-> (Date, Int --> Date)multi infix:<-> (Date, Date --> Int)
Takes a date to subtract from and either an Int
, representing the number of days to subtract, or another Date
object. Returns a new Date
object or the number of days between the two dates, respectively.
say Date.new('2016-12-25') - Date.new('2016-12-24'); # OUTPUT: «1»say Date.new('2015-12-25') - Date.new('2016-11-21'); # OUTPUT: «-332»say Date.new('2016-11-21') - 332; # OUTPUT: «2015-12-25»
sub infix:<+>§
multi infix:<+> (Date, Int --> Date)multi infix:<+> (Int, Date --> Date)
Takes an Int
and adds that many days to the given Date
object.
say Date.new('2015-12-25') + 332; # OUTPUT: «2016-11-21»say 1 + Date.new('2015-12-25'); # OUTPUT: «2015-12-26»