Author: lue
Date: 2010-04-03 20:18:43 +0200 (Sat, 03 Apr 2010)
New Revision: 30293
Modified:
docs/Perl6/Spec/S32-setting-library/Temporal.pod
Log:
[P6 Spec] completely changed S32::Temporal
Modified: docs/Perl6/Spec/S32-setting-library/Temporal.pod
===================================================================
--- docs/Perl6/Spec/S32-setting-library/Temporal.pod 2010-04-03 13:03:58 UTC
(rev 30292)
+++ docs/Perl6/Spec/S32-setting-library/Temporal.pod 2010-04-03 18:18:43 UTC
(rev 30293)
@@ -17,12 +17,13 @@
Tim Nelson <wayl...@wayland.id.au>
Daniel Ruoso <dan...@ruoso.com>
Dave Rolsky <auta...@urth.org>
+ Matthew (lue) <rnd...@gmail.com>
=head1 VERSION
Created: 19 Mar 2009 extracted from S29-functions.pod and S16-IO.pod
- Last Modified: 18 Feb 2010
+ Last Modified: 2 Apr 2010
Version: 6
The document is a draft.
@@ -31,224 +32,144 @@
repository under /docs/Perl6/Spec/S32-setting-library/Temporal.pod so edit it
there in
the SVN repository if you would like to make changes.
-=head1 Roles
+=head1 Temporal
-=head2 Instant
+Time is just a jumbled iTem.
-The epoch used in Perl 6 to represent time instants is the
-International Atomic Time - TAI - which is independent of calendars,
-timezones as well as leap seconds. Of course Perl can't go beyond the
-machine to get a real TAI value, but it should perform any
-platform-specific transformation to give you the most precise value it
-can for the TAI.
+Temporal is divided into two parts: date and time.
- our Instant sub time()
+=head2 Time
-Returns a TAI epoch value for the current time.
+Time is called upon as such:
-=head2 Duration
-
-Duration objects describe an amount of time, it's the fundamental type
-for time math. The base Duration object is only TAI-seconds aware, but
-if you use its constructor with any other parameters it will delegate
-to Gregorian::Duration in order to make the most common cases easier.
-
-The following attribute is declared:
-
=over
-=item tai
+=item Time.new($timesystem = $*CLOCK, $time = $*NOW)
-Returns the amount of TAI seconds described in this duration. Note
-that usually you shouldn't be doing math with the result of .tai for
-different datetime and duration objects. The result of .tai might also
-be an estimated value for Duration types that depend on an anchor date
-(i.e.: 1 month).
+Creates a new Time object. $timesystem is what clock you wish to use. If
unspecified, whatever is in $*CLOCK is used. $time specifies the $time, it
defaults to what is in $*NOW. What you enter in $time should match the format
that $timesystem is in. $*NOW and $*CLOCK should be specified in the same
format (i.e., if $*CLOCK is 'unixepoch', $*NOW should be something like
127666216.432)
+Possible (string!) values for $timesystem (and therefore $*CLOCK) are:
-=back
-
-=head2 Calendar
-
-Every DateTime needs to follow the rules of a given calendar. The
-default is the Gregorian calendar, but several other calendars exist
-in the real world.
-
-The current default calendar is stored in $*CALENDAR.
-
=over
-=item method calendartime($epoch = time(), *%options)
+=item * 12hour
-=item multi calendartime($epoch = time(), $calendar = $*CALENDAR, *%options)
+=item * 24hour (this and 12hour are essentialy the same system, but for
simplicity they are separate)
-Returns a DateTime object in the current calendar for the given TAI
-epoch time. Each calendar type might accept different options.
+=item * hextime
-Note that simply changing the current calendar is not magically going
-to make any code portable to different calendars. The code using it
-should either use only the methods in the generic Calendar and
-DateTime roles, or special case for the known Calendars.
+=item * unixepoch
-=item method formatter is rw
+=item * tai
-The default formatter object used for DateTime objects in this
-calendar.
-
=back
-=head2 Calendar::TimeZoneObservant
+If the time system you want is not up on the list, you are at the mercy of the
implementation (which can, of course, add in rarer time systems) and/or
available libraries and other addons. A shortcut to the time (in the default as
defined by $*CLOCK) is through the $*TIME variable.
-This is a generic role used to identify all calendars that observe the
-time zones. Not all calendars are time-zone observants. One way or
-another, two multi subs will be available that depend on a time-zone
-observant calendar. They will fail if you try to call them with a
-non-tz calendar.
+=item Time.convert($convertto = $*CLOCK)
-This role also implies that the calendartime method might receive a
-time-zone named parameter.
+returns the time converted to the time system specified in $convertto. If you
were to call convert(), then it would default to what's in $*CLOCK
-=over
+=item Time.format($formatto)
-=item method gmtime($epoch = time(), *%options )
+returns the time formatted to the way specified in $formatto. If the time has
no options for formatting (for example hextime can be either 3_A0_9 or .3A09,
but a 24 hour clock is typically only formatted as 15:17), or $formatto is left
blank, it is sent back without processing.
-=item multi gmtime($epoch = time(), $calendar = $*CALENDAR, *%options)
-
-Returns a DateTime object in the GMT timezone, considering $epoch to
-be TAI. Same as:
-
- calendartime($epoch, $calendar, :time-zone('GMT'))
-
-=item method localtime($epoch = time(), *%options )
-
-=item multi localtime($epoch = time(), $calendar = $*CALENDAR, *%options)
-
-Returns a DateTime object in the local timezone taken from the system,
-considering $epoch to be TAI. Same as:
-
- calendartime($epoch, $calendar, :time-zone('local'))
-
=back
-=head2 DateTime
+=head2 Date
-The generic DateTime role specifies the basic operations that should
-be possible independent of the Calendar being used, and are,
-therefore, considerably restricted.
+Date is called in a similar fashion:
-In order to make it easier to deal with the most common scenario, the
-constructor of the bare DateTime type will delegate to
-Gregorian::DateTime.
-
-It defines the following attributes.
-
=over
-=item formatter
+=item Date.new($datesystem = $*CALENDAR, $date = $*TODAY)
-The object that will stringify this specific object.
+Defines a new Date object. $datesystem defines the calendar to use. If not
specified, it defaults to what is in $*CALENDAR. $date specifies the date. If
not specified, then the date used is the one in $*TODAY. Make sure $date is in
the same format as specified in $datesystem. $*CALENDAR and $*TODAY should be
specified in the same calendar (i.e. if $*CALENDAR is 'Gregorian' $*TODAY
should be something like '12-31-10', depending on how things are formatted)
+Possible string values for $datesystem (and therefore $*CALENDAR) are:
-=item calendar
-
-Returns the calendar that governs this datetime.
-
-=back
-
-And the following methods
-
=over
-=item tai
+=item * Gregorian
-Returns the TAI value for this specific datetime, useful for
-inter-calendar comparison and conversion.
+=item * Julian (the predecessor of Gregorian. NOT the astronomical Julian Year)
+=item * Discordian
+
=back
-=head2 TimeZone
+There aren't that many calendar in use today (heck, Discordian is up there
only because you can get it using ddate, a command found on almost every Linux
distribution). If you need something different from what is on the list, you
are at the mercy of the implementation and any available libraries/modules. You
can shortcut to the current date in the default calendar (in $*CALENDAR), by
using the $*DATE variable.
-This is the base for the entire time-zone database with the complete
-information about daylight-saving-time and other variations that can
-happen.
+=item Date.convert($convertto = $*CALENDAR)
-This should be a straight port from perl 5 DateTime::TimeZone module.
+Returns the date in the format specified in $convertto (defaults to what's in
$*CALENDAR)
-=head2 TimeRange
+=item Date.format($formatto)
-This object represents a given period of time, and may exclude either endpoint.
-It might be composed by:
+Formats the date (i.e. 4/2/10 or 2 April 2010 in Gregorian) to what's
specified in $formatto. If unspecified, it returns the date without any
processing.
- $datetime1 .. $datetime2
- $datetime1 ^.. $datetime2
- $datetime1 ..^ $datetime2
+=back
-These may be iterated, but only on seconds. To iterate with some
-other duration, you may use the series operator to produce a series
-of datetimes:
+=head2 Duration
- $datetime1, *+$duration ... $datetime2
+A duration is a certain length of time (i.e. from 12:00 to 14:15, the duration
can be said to be 2:15).
-=head2 Gregorian::Calendar
+=over
-Also known as the "civil" calendar. This is the calendar used in most
-of the world, specially in the western countries.
+=item Duration.new($begin = 0, $end, $format)
-=head2 Gregorian::DateTime
+Specifies a new Duration object. $begin is at the beginning of duration (i.e.
4 seconds), $end is the end of the duration (i.e. 72 seconds), and $format is
in what format $begin and $end are in. $format can be anything that either
$*CLOCK or $*CALENDAR can be.
-The gregorian DateTime declares the following additional attributes.
+=item Duration.convert($convertto)
-=over
+returns the Duration in the format as specified by $convertto. It defaults to
doing nothing.
-=item year
+=item Duration.format($formatto)
-=item month
+Returns the Duration formatted as specified in $formatto. If the time given
cannot be formatted (i.e. 13:47, which has no common alternative format), it
returns the duration as it was entered.
-=item day
+=back
-=item minute
+=head2 Arithmetic
-=item second
+Any sort of arithmetic between Time, Date, and Duration objects require these
objects to give the equivalent of that object's data (13:15 or 3/4/10) in TAI
seconds first. What's returned is a Duration object, because it can be
formatted however you wish using Duration's convert and format.
-=item nanosecond
+=head2 Specifics on formats
-=item time-zone
+Whenever a date/time format is added/removed to/from the spec, please update
this listing. This listing describes how each date/time format stores
information, and available formatting.
-=back
+Formatting options are those used in the unix utility date (search for
Date_(Unix) on wikipedia for the formatting options), mapped to the current
date/time as best as possible.
-The following methods provide additional information
-
=over
-=item week-of-year
+=item Twelve Hour
-=item day-of-week
+The twelve-hour format should store the data as an array, containing the hour,
minute, second, AM/PM, and if the interpreter chooses, parts less than a
second. The only format it can be in is 12:31:07 AM)
-=item week-of-month
+=item Twenty-Four Hour
-=item year-of-week
+The twenty-four-hour format is the same as 12 Hour, except for the the fact
that AM/PM is not needed.
-=back
+=item Hextime
-=head2 Gregorian::Duration
+Hextime should be stored as an array of strings, consisting of the hexhour,
hexminute, and hexsecond (alternatively, it could also be held as a hex hour,
hex maxime, hex minute, and hex second). The time can be formatted either as
.3A02 or 3_A0_2 (if stored as maxime & hexminute, they must combine as one. i.e
in 3_A0_2, A is the maxime, and 0 is the hexminute. If stored as
hex-hour/minute/second, then A0 is the minute.)
-The gregorian Duration declares the following attributes.
+=item Unix Epoch & TAI
-=over
+Both are stored as a # of seconds, and only shown/formatted as such.
-=item year
+=item Gregorian
-=item month
+Gregorian ought to be stored in an array as the day, month, and year, along
with the name of the day. Year can either be a +/- number, or you can add
another element for AD and BC. It can be formatted in any myriad of ways,
including: "Sunday, April 4th, 2010", or "4/2/10".
-=item day
+=item Julian
-=item minute
+Same as Gregorian in terms of storage and formatting. (Just remember that
Julian != Gregorian)
-=item second
+=item Discordian
-=item nanosecond
+Stored in an array as the year, the season, and the day of the season.
Formatting is similar to Gregorian & Julian (see the man page for ddate for a
list of Discordian format options)
=back
-
=head1 Additions
Please post errors and feedback to perl6-language. If you are making
