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Temporal.pm
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Temporal.pm
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my class DateTime { ... }
my class Date { ... }
my @UNITS = <second minute hour day week month year> X~ '', 's';
my role Dateish {
method IO(|c) { IO::Path.new(self) }
method is-leap-year($y = $.year) {
$y %% 4 and not $y %% 100 or $y %% 400
}
method days-in-month($year = $.year, $month = $.month) {
$month == 2 ?? self.is-leap-year($year) ?? 29 !! 28
!! $month == 4|6|9|11 ?? 30
!! 31
}
method daycount-from-ymd(Int() $y is copy, Int() $m is copy, $d) {
# taken from <http://www.merlyn.demon.co.uk/daycount.htm>
if $m < 3 {
$m += 12;
--$y;
}
-678973 + $d + (153 * $m - 2) div 5
+ 365 * $y + $y div 4
- $y div 100 + $y div 400;
}
method ymd-from-daycount($daycount) {
# taken from <http://www.merlyn.demon.co.uk/daycount.htm>
my int $day = $daycount.Int + 678881;
my int $t = (4 * ($day + 36525)) div 146097 - 1;
my int $year = 100 * $t;
$day = $day - (36524 * $t + ($t div 4));
$t = (4 * ($day + 366)) div 1461 - 1;
$year = $year + $t;
$day = $day - (365 * $t + ($t div 4));
my int $month = (5 * $day + 2) div 153;
$day = $day - ((2 + $month * 153) div 5 - 1);
if ($month > 9) {
$month = $month - 12;
$year = $year + 1;
}
($year, $month + 3, $day)
}
method get-daycount {
self.daycount-from-ymd($.year, $.month, $.day)
}
method day-of-month() { $.day }
method day-of-week($daycount = self.get-daycount) {
($daycount + 2) % 7 + 1
}
method week() { # algorithm from Claus Tøndering
my $a = $.year - ($.month <= 2).floor.Int;
my $b = $a div 4 - $a div 100 + $a div 400;
my $c = ($a - 1) div 4 - ($a - 1) div 100 + ($a - 1) div 400;
my $s = $b - $c;
my $e = $.month <= 2 ?? 0 !! $s + 1;
my $f = $.day + do $.month <= 2
?? 31*($.month - 1) - 1
!! (153*($.month - 3) + 2) div 5 + 58 + $s;
my $g = ($a + $b) % 7;
my $d = ($f + $g - $e) % 7;
my $n = $f + 3 - $d;
$n < 0 ?? ($.year - 1, 53 - ($g - $s) div 5)
!! $n > 364 + $s ?? ($.year + 1, 1)
!! ($.year, $n div 7 + 1);
}
method week-year() {
self.week.[0]
}
method week-number() {
self.week.[1]
}
method weekday-of-month {
($.day - 1) div 7 + 1
}
method day-of-year() {
[+] $.day, map { self.days-in-month($.year, $^m) }, 1 ..^ $.month
}
method check-value($val is copy, $name, $range, :$allow-nonint) {
$val = $allow-nonint ?? +$val !! $val.Int;
$val ~~ $range
or X::OutOfRange.new(
what => $name,
got => $val,
range => $range,
).throw;
}
method check-date {
self.check-value($.month, 'month', 1 .. 12);
self.check-value($.day, "day of $.year/$.month",
1 .. self.days-in-month);
}
method truncate-parts(Cool:D $unit, %parts? is copy) {
# Helper for DateTime.truncated-to and Date.truncated-to.
X::DateTime::InvalidDeltaUnit.new(:$unit).throw
unless $unit eq any(@UNITS);
if $unit eq 'week' | 'weeks' {
my $dc = self.get-daycount;
my $new-dc = $dc - self.day-of-week($dc) + 1;
%parts<year month day> =
self.ymd-from-daycount($new-dc);
} else { # $unit eq 'month' | 'months' | 'year' | 'years'
%parts<day> = 1;
$unit eq 'year' and %parts<month> = 1;
}
%parts;
}
}
sub default-formatter(DateTime $dt, Bool :$subseconds) {
# ISO 8601 timestamp (well, not strictly ISO 8601 if $subseconds
# is true)
my $o = $dt.offset;
$o %% 60
or warn "Default DateTime formatter: offset $o not divisible by 60.\n";
sprintf '%04d-%02d-%02dT%02d:%02d:%s%s',
$dt.year, $dt.month, $dt.day, $dt.hour, $dt.minute,
$subseconds
?? $dt.second.fmt('%09.6f')
!! $dt.whole-second.fmt('%02d'),
do $o
?? sprintf '%s%02d%02d',
$o < 0 ?? '-' !! '+',
($o.abs / 60 / 60).floor,
($o.abs / 60 % 60).floor
!! 'Z';
}
sub get-local-timezone-offset {
my $utc = DateTime.new(now).posix.Int;
my Mu $fia := nqp::p6decodelocaltime(nqp::unbox_i($utc));
my $second = nqp::p6box_i(nqp::atpos_i($fia, 0));
my $minute = nqp::p6box_i(nqp::atpos_i($fia, 1));
my $hour = nqp::p6box_i(nqp::atpos_i($fia, 2));
my $day = nqp::p6box_i(nqp::atpos_i($fia, 3));
my $month = nqp::p6box_i(nqp::atpos_i($fia, 4));
my $year = nqp::p6box_i(nqp::atpos_i($fia, 5));
my $local = DateTime.new(:$year, :$month, :$day, :$hour, :$minute, :$second);
my $ltime = $local.posix(True).Int;
$ltime - $utc;
}
my class DateTime does Dateish {
has Int $.year;
has Int $.month = 1;
has Int $.day = 1;
has Int $.hour = 0;
has Int $.minute = 0;
has $.second = 0.0;
has $.timezone = 0; # UTC
has &.formatter = &default-formatter;
# Not an optimization but a necessity to ensure that
# $dt.utc.local.utc is equivalent to $dt.utc. Otherwise,
# DST-induced ambiguity could ruin our day.
multi method new() {
fail "Must provide arguments to DateTime.new()";
}
multi method new(Int :$year!, :&formatter=&default-formatter, *%_) {
my $dt = self.bless(:$year, :&formatter, |%_);
$dt.check-date;
$dt.check-time;
$dt;
}
method check-time {
# Asserts the validity of and numifies $!hour, $!minute, and $!second.
self.check-value($!hour, 'hour', 0 ..^ 24);
self.check-value($!minute, 'minute', 0 ..^ 60);
self.check-value($!second, 'second', 0 ..^ 62, :allow-nonint);
if $!second >= 60 {
# Ensure this is an actual leap second.
self.second < 61
or X::OutOfRange.new(
what => 'second',
range => (0..^60),
got => self.second,
comment => 'No second 61 has yet been defined',
).throw;
my $dt = self.utc;
$dt.hour == 23 && $dt.minute == 59
or X::OutOfRange.new(
what => 'second',
range => (0..^60),
got => self.second,
comment => 'a leap second can occur only at hour 23 and minute 59 UTC',
).throw;
my $date = sprintf '%04d-%02d-%02d',
$dt.year, $dt.month, $dt.day;
$date eq any(tai-utc::leap-second-dates)
or X::OutOfRange.new(
what => 'second',
range => (0..^60),
got => self.second,
comment => "There is no leap second on UTC $date",
).throw;
}
}
multi method new(Date:D :$date!, *%_) {
self.new(year => $date.year, month => $date.month,
day => $date.day, |%_)
}
multi method new(Instant:D $i, :$timezone=0, :&formatter=&default-formatter) {
my ($p, $leap-second) = $i.to-posix;
my $dt = self.new: floor($p - $leap-second).Int, :&formatter;
$dt.clone(second => ($dt.second + $p % 1 + $leap-second)
).in-timezone($timezone);
}
multi method new(Int:D $time is copy, :$timezone=0, :&formatter=&default-formatter) {
# Interpret $time as a POSIX time.
my $second = $time % 60; $time = $time div 60;
my $minute = $time % 60; $time = $time div 60;
my $hour = $time % 24; $time = $time div 24;
# Day month and leap year arithmetic, based on Gregorian day #.
# 2000-01-01 noon UTC == 2451558.0 Julian == 2451545.0 Gregorian
$time += 2440588; # because 2000-01-01 == Unix epoch day 10957
my $a = $time + 32044; # date algorithm from Claus Tøndering
my $b = (4 * $a + 3) div 146097; # 146097 = days in 400 years
my $c = $a - (146097 * $b) div 4;
my $d = (4 * $c + 3) div 1461; # 1461 = days in 4 years
my $e = $c - ($d * 1461) div 4;
my $m = (5 * $e + 2) div 153; # 153 = days in Mar-Jul Aug-Dec
my $day = $e - (153 * $m + 2) div 5 + 1;
my $month = $m + 3 - 12 * ($m div 10);
my $year = $b * 100 + $d - 4800 + $m div 10;
self.bless(:$year, :$month, :$day,
:$hour, :$minute, :$second,
:&formatter).in-timezone($timezone);
}
multi method new(Str $format, :$timezone is copy = 0, :&formatter=&default-formatter) {
$format ~~ /^ (\d**4) '-' (\d\d) '-' (\d\d) T (\d\d) ':' (\d\d) ':' (\d\d) (Z || (<[\-\+]>) (\d\d) (':'? (\d\d))? )? $/
or X::Temporal::InvalidFormat.new(
invalid-str => $format,
target => 'DateTime',
format => 'an ISO 8601 timestamp (yyyy-mm-ddThh:mm:ssZ or yyyy-mm-ddThh:mm:ss+0100)',
).throw;
my $year = (+$0).Int;
my $month = (+$1).Int;
my $day = (+$2).Int;
my $hour = (+$3).Int;
my $minute = (+$4).Int;
my $second = +$5;
if $6 {
$timezone
and X::DateTime::TimezoneClash.new.throw;
if $6 eq 'Z' {
$timezone = 0;
} else {
$timezone = (($6[1]*60 + ($6[2][0] // 0)) * 60).Int;
# RAKUDO: .Int is needed to avoid to avoid the nasty '-0'.
$6[0] eq '-' and $timezone = -$timezone;
}
}
self.new(:$year, :$month, :$day, :$hour, :$minute,
:$second, :$timezone, :&formatter);
}
method now(:$timezone=$*TZ, :&formatter=&default-formatter) returns DateTime:D {
self.new(now, :$timezone, :&formatter)
}
method clone(*%_) {
my %args = :$!year, :$!month, :$!day, :$!hour, :$!minute,
:$!second, :$!timezone, :&!formatter, %_;
self.new(|%args);
}
method clone-without-validating(*%_) { # A premature optimization.
my %args = :$!year, :$!month, :$!day, :$!hour, :$!minute,
:$!second, :$!timezone, :&!formatter, %_;
self.bless(|%args);
}
method Instant() {
Instant.from-posix: self.posix + $.second % 1, $.second >= 60;
}
method posix($ignore-timezone?) {
$ignore-timezone or self.offset == 0
or return self.utc.posix;
# algorithm from Claus Tøndering
my $a = (14 - $.month.Int) div 12;
my $y = $.year.Int + 4800 - $a;
my $m = $.month.Int + 12 * $a - 3;
my $jd = $.day + (153 * $m + 2) div 5 + 365 * $y
+ $y div 4 - $y div 100 + $y div 400 - 32045;
($jd - 2440588) * 24 * 60 * 60
+ 60*(60*$.hour + $.minute) + self.whole-second;
}
method offset {
$!timezone.Int;
}
method offset-in-minutes {
$!timezone.Int / 60;
}
method offset-in-hours {
$!timezone.Int / 60 / 60;
}
method later(*%unit) {
die "More than one time unit supplied"
if %unit.keys > 1;
die "No time unit supplied"
unless %unit.keys;
my ($unit, $amount) = %unit.kv;
X::DateTime::InvalidDeltaUnit.new(:$unit).throw
unless $unit eq any(@UNITS);
my ($hour, $minute) = $!hour, $!minute;
my $date;
given $unit {
when 'second' | 'seconds' {
return self.new(self.Instant + $amount);
}
when 'minute' | 'minutes' { $minute += $amount; proceed }
$hour += floor($minute / 60);
$minute %= 60;
when 'hour' | 'hours' { $hour += $amount; proceed }
my $day-delta += floor($hour / 24);
$hour %= 24;
when 'day' | 'days' { $day-delta += $amount; proceed }
when 'week' | 'weeks' { $day-delta += 7 * $amount; proceed }
when 'month' | 'months' {
my ($month, $year) = $!month, $!year;
$month += $amount;
$year += floor(($month - 1) / 12);
$month = ($month - 1) % 12 + 1;
$date = Date.new(:$year, :$month, :$!day);
succeed;
}
when 'year' | 'years' {
my $year = $!year + $amount;
$date = Date.new(:$year, :$!month, :$!day);
succeed;
}
my $daycount = Date.new(self).daycount;
$daycount += $day-delta;
$date = Date.new-from-daycount($daycount);
}
my $second = $!second;
if $second > 59 && $date ne any(tai-utc::leap-second-dates) {
$second -= 60;
$minute++;
if $minute > 59 {
$minute -= 60;
$hour++;
if $hour > 23 {
$hour -= 24;
$date++;
}
}
}
self.new(:$date, :$hour, :$minute, :$second);
}
method earlier(*%unit) {
self.later(| -<< %unit);
}
method truncated-to(Cool $unit) {
my %parts;
given $unit {
%parts<second> = self.whole-second;
when 'second' {}
%parts<second> = 0;
when 'minute' {}
%parts<minute> = 0;
when 'hour' {}
%parts<hour> = 0;
when 'day' {}
# Fall through to Dateish.
%parts = self.truncate-parts($unit, %parts);
}
self.clone-without-validating(|%parts);
}
method whole-second() {
floor($.second).Int
}
method in-timezone($timezone) {
$timezone eqv $!timezone and return self;
my $old-offset = self.offset;
my $new-offset = $timezone.Int;
my %parts;
# Is the logic for handling leap seconds right?
# I don't know, but it passes the tests!
my $a = ($!second >= 60 ?? 59 !! $!second)
+ $new-offset - $old-offset;
%parts<second> = $!second >= 60 ?? $!second !! ($a % 60).Int;
my $b = $!minute + floor $a / 60;
%parts<minute> = ($b % 60).Int;
my $c = $!hour + floor $b / 60;
%parts<hour> = ($c % 24).Int;
# Let Dateish handle any further rollover.
floor $c / 24 and %parts<year month day> =
self.ymd-from-daycount\
(self.get-daycount + floor $c / 24);
self.clone-without-validating:
:$timezone, |%parts;
}
method utc() {
self.in-timezone(0)
}
method local() {
self.in-timezone($*TZ)
}
method Date() {
Date.new(:$.year, :$.month, :$.day);
}
method Str() {
&!formatter(self)
}
multi method perl(DateTime:D:) {
sprintf '%s.new(%s)', self.^name, join ', ', map { "{.key} => {.value}" }, do
:$.year, :$.month, :$.day, :$.hour, :$.minute,
second => $.second.perl,
(timezone => $.timezone.perl
unless $.timezone === 0),
(formatter => $.formatter.perl
unless &.formatter eqv &default-formatter)
}
multi method gist(DateTime:D:) {
self.Str;
}
}
my class Date does Dateish {
has Int $.year;
has Int $.month = 1;
has Int $.day = 1;
has Int $.daycount;
method !set-daycount($dc) { $!daycount = $dc }
method get-daycount { $!daycount }
multi method new(:$year!, :$month = 1, :$day = 1) {
my $d = self.bless(:$year, :$month, :$day);
$d.check-date;
$d!set-daycount(self.daycount-from-ymd($year,$month,$day));
$d;
}
multi method new($year, $month, $day) {
self.new(:$year, :$month, :$day);
}
multi method new(Str $date) {
$date ~~ /^ \d\d\d\d '-' \d\d '-' \d\d $/
or X::Temporal::InvalidFormat.new(
invalid-str => $date,
format => 'yyyy-mm-dd',
).throw;
self.new(|$date.split('-').map({.Int}));
}
multi method new() {
my $n = self.today;
if $n.month == 12 && $n.day >= 24 {
self.new($n.year + 1, 12, 24);
} else {
self.new($n.year, 12, 24);
}
}
multi method new(Dateish $d) {
self.bless(
:year($d.year), :month($d.month), :day($d.day),
:daycount(self.daycount-from-ymd($d.year,$d.month,$d.day))
);
}
multi method new(Instant $i) {
my $dt = DateTime.new($i);
self.new($dt);
}
multi method WHICH(Date:D:) {
nqp::box_s(
nqp::concat(
nqp::concat(nqp::unbox_s(self.^name), '|'),
nqp::unbox_i($!daycount)
),
ObjAt
);
}
method new-from-daycount($daycount) {
my ($year, $month, $day) = self.ymd-from-daycount($daycount);
self.bless(:$daycount, :$year, :$month, :$day);
}
method today() {
self.new(DateTime.now);
}
method truncated-to(Cool $unit) {
self.clone(|self.truncate-parts($unit));
}
method later(*%unit) {
die "More than one time unit supplied"
if %unit.keys > 1;
my ($unit, $amount) = %unit.kv;
X::DateTime::InvalidDeltaUnit.new(:$unit).throw
unless $unit eq any(@UNITS);
my $date;
given $unit {
X::DateTime::InvalidDeltaUnit.new(:$unit).throw
when 'second' | 'seconds' | 'minute' | 'minutes' | 'hour' | 'hours';
my $day-delta;
when 'day' | 'days' { $day-delta = $amount; proceed }
when 'week' | 'weeks' { $day-delta = 7 * $amount; proceed }
when 'month' | 'months' {
my ($month, $year) = $!month, $!year;
$month += $amount;
$year += floor(($month - 1) / 12);
$month = ($month - 1) % 12 + 1;
$date = self.new(:$year, :$month, :$!day);
succeed;
}
when 'year' | 'years' {
my $year = $!year + $amount;
$date = self.new(:$year, :$!month, :$!day);
succeed;
}
$date = self.new-from-daycount(self.daycount + $day-delta);
}
$date;
}
method earlier(*%unit) {
self.later(| -<< %unit);
}
method clone(*%_) {
my %args = :$!year, :$!month, :$!day, %_;
self.new(|%args);
}
method succ() {
self.new-from-daycount($!daycount + 1);
}
method pred() {
self.new-from-daycount($!daycount - 1);
}
multi method gist(Date:D:) {
sprintf '%04d-%02d-%02d', $.year, $.month, $.day;
}
multi method Str(Date:D:) {
sprintf '%04d-%02d-%02d', $.year, $.month, $.day;
}
multi method perl(Date:D:) {
self.^name ~ ".new($.year.perl(), $.month.perl(), $.day.perl())";
}
multi method ACCEPTS(Date:D: DateTime:D $dt) {
return $dt.year == $.year && $dt.month == $.month && $dt.day == $.day;
}
}
multi sub infix:<+>(Date:D $d, Int:D $x) {
Date.new-from-daycount($d.daycount + $x)
}
multi sub infix:<+>(Int:D $x, Date:D $d) {
Date.new-from-daycount($d.daycount + $x)
}
multi sub infix:<->(Date:D $d, Int:D $x) {
Date.new-from-daycount($d.daycount - $x)
}
multi sub infix:<->(Date:D $a, Date:D $b) {
$a.daycount - $b.daycount;
}
multi sub infix:<cmp>(Date:D $a, Date:D $b) {
$a.daycount cmp $b.daycount
}
multi sub infix:«<=>»(Date:D $a, Date:D $b) {
$a.daycount <=> $b.daycount
}
multi sub infix:<==>(Date:D $a, Date:D $b) {
$a.daycount == $b.daycount
}
multi sub infix:«<=»(Date:D $a, Date:D $b) {
$a.daycount <= $b.daycount
}
multi sub infix:«<»(Date:D $a, Date:D $b) {
$a.daycount < $b.daycount
}
multi sub infix:«>=»(Date:D $a, Date:D $b) {
$a.daycount >= $b.daycount
}
multi sub infix:«>»(Date:D $a, Date:D $b) {
$a.daycount > $b.daycount
}
multi sub INITIALIZE_DYNAMIC('$*TZ') {
PROCESS::<$TZ> = get-local-timezone-offset();
}
sub sleep($seconds = Inf --> Nil) {
if $seconds == Inf || nqp::istype($seconds,Whatever) {
nqp::sleep(1e16) while True;
}
elsif $seconds > 0 {
nqp::sleep($seconds.Num);
}
Nil;
}
sub sleep-timer (Real $seconds = Inf --> Duration) {
if $seconds <= 0 {
Duration.new(0);
}
else {
my $time1 = now;
nqp::sleep($seconds.Num);
Duration.new( ( $seconds - (now - $time1) ) max 0 );
}
}
sub sleep-till (Instant $till --> Bool) {
my $seconds = $till - now;
return False if $seconds < 0;
1 while $seconds = sleep-timer($seconds);
True;
}
# =begin pod
#
# =head1 SEE ALSO
# Perl 6 spec <S32-Temporal|http://design.perl6.org/S32/Temporal.html>.
# The Perl 5 DateTime Project home page L<http://datetime.perl.org>.
# Perl 5 perldoc L<doc:DateTime> and L<doc:Time::Local>.
#
# The best yet seen explanation of calendars, by Claus Tøndering
# L<Calendar FAQ|http://www.tondering.dk/claus/calendar.html>.
# Similar algorithms at L<http://www.hermetic.ch/cal_stud/jdn.htm>
# and L<http://www.merlyn.demon.co.uk/daycount.htm>.
#
# <ISO 8601|http://en.wikipedia.org/wiki/ISO_8601>
# <Time zones|http://en.wikipedia.org/wiki/List_of_time_zones>
#
# As per the recommendation, the strftime() method has bee moved into a
# loadable module called DateTime::strftime.
#
# =end pod
# vim: ft=perl6 expandtab sw=4