NAME

Date::ICal - Perl extension for ICal date objects.

SYNOPSIS

use Date::ICal;

$ical = Date::ICal->new( ical => '19971024T120000' );
$ical = Date::ICal->new( epoch => time );

$hour = $ical->hour;
$year = $ical->year;

$ical_string = $ical->ical;
$epoch_time = $ical->epoch;

$ical->epoch( time+60 ); # Set the time a minute ahead

DESCRIPTION

Date::ICal talks the ICal date format, and is intended to be a base class for other date/calendar modules that know about ICal time format also.

See http://dates.rcbowen.com/unified.txt for details

METHODS

Date::ICal has the following methods available:

new

A new Date::ICal object can be created with any valid ICal string:

my $ical = Date::ICal->new( ical => '19971024T120000' );

Or with any epoch time:

my $ical = Date::ICal->new( epoch => time );

If you call new without any arguments, you'll get a Date::ICal object that is set to the time right now.

my $ical = Date::ICal->new();

ical

$ical_string = $ical->ical;

$ical->ical( '19981016' );

Retrieves, or sets, the date on the object, using any valid ICal date/time string.

The ICal represenatation is the one authoritative value in the object, and so if it is changed, it must be able to indicate that the other values are no longer valid. Or set the correctly. Or something. Comments welcomed.

epoch

$epoch_time = $ical->epoch;

$ical->epoch( 98687431 );

Sets, or retrieves, the epoch time represented by the object, if it is representable as such. (Dates before 1971 or after 2038 will not have an epoch representation.)

Internals note: The ICal representation of the date is considered the only authoritative one. This means that we may need to reconstruct the epoch time from the ICal representation if we are not sure that they are in synch. We'll need to do clever things to keep track of when the two may not be in synch. And, of course, the same will go for any subclasses of this class.

Other Accessors

second
minute
hour
day
month
year

Generic set/get methods.

$sec = $t->second;

$t->minute(12);

_parse_ical

$self->_parse_ical;

_parse_ical is an internal method (although I suppose you could call it externally if you really wanted to) which repopulates other attributes based on the ical field. This should be called by various methods if an attribute is undefined.

_format_ical

$self->_format_ical;

This is an internal method used to rebuild the ical string when one component, such as the second or month field has been changed.

_epoch_from_ical

$self->_epoch_from_ical;

This is an internal method used to determine the epoch time from the ical value.

add

$date->add( %hash ); # Hash of day, hour, min, etc, values
$date->add( ical => $ical_duration_string );

Adds a duration to a Date::ICal object.

Duration should be passed in as either an ical string, or as a hash of date/time properties.

The result will be normalized. That is, the output time will have meaningful values, rather than being 48:73 pm on the 34th of hexadecember.

add

$self->add( month=>2 );
$self->add( duration =>'P1W' );

_normal

$self->_normal($attrib,$suggestednewvalue);

This attempts to flatten out of range values to what they should be and adjust
adjcent values accordingly.  For instance passing 'month' and 14 to _normal
would result in the year being incremented and the ical month field being set
to two

$self->_month_length();

This utility returns the length of the current ical month.

$self->_alter_period($attrib);

called by add and _normal to do the hard work of flattening the values

add_duration

$self->add_duration('P2W');

Adds a rfc2445 duration to current $self->{ical}

compare

$cmp = $date2 Date::ICal::compare $date2;

@dates = sort {$a Date::ICal::compare $b} @dates;

Compare two Date::ICal objects. Symantics should be compatible with sort.

TODO

- add support for initializing dates

- add timezone support, including moving between timezones

- add arithmetic methods: add, subtract, ...

- add gmtime and localtime methods, perhaps?

AUTHOR

Rich Bowen (DrBacchus) rbowen@rcbowen.com

SEE ALSO

datetime@perl.org mailing list

http://reefknot.org/

http://dates.rcbowen.com/

Time::Local

Net::ICal

cpanm Date::ICal

perl -MCPAN -e shell
install Date::ICal