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use warnings;
use strict;
package Data::ICal::Entry::TimeZone::Standard;
use base qw/Data::ICal::Entry/;
=head1 NAME
Data::ICal::Entry::TimeZone::Standard - Represents a Standard Time base offset from UTC for parent TimeZone
=head1 SYNOPSIS
=head1 DESCRIPTION
A time zone is unambiguously defined by the set of time
measurement rules determined by the governing body for a given
geographic area. These rules describe at a minimum the base offset
from UTC for the time zone, often referred to as the Standard Time
offset. Many locations adjust their Standard Time forward or backward
by one hour, in order to accommodate seasonal changes in number of
daylight hours, often referred to as Daylight Saving Time. Some
locations adjust their time by a fraction of an hour. Standard Time
is also known as Winter Time. Daylight Saving Time is also known as
Advanced Time, Summer Time, or Legal Time in certain countries. The
following table shows the changes in time zone rules in effect for
New York City starting from 1967. Each line represents a description
or rule for a particular observance.
Effective Observance Rule
Date (Date/Time) Offset Abbreviation
1967-* last Sun in Oct, 02:00 -0500 EST
1967-1973 last Sun in Apr, 02:00 -0400 EDT
1974-1974 Jan 6, 02:00 -0400 EDT
1975-1975 Feb 23, 02:00 -0400 EDT
1976-1986 last Sun in Apr, 02:00 -0400 EDT
1987-* first Sun in Apr, 02:00 -0400 EDT
Note: The specification of a global time zone registry is not
addressed by this document and is left for future study.
However, implementers may find the Olson time zone database [TZ]
a useful reference. It is an informal, public-domain collection
of time zone information, which is currently being maintained by
volunteer Internet participants, and is used in several
operating systems. This database contains current and historical
time zone information for a wide variety of locations around the
globe; it provides a time zone identifier for every unique time
zone rule set in actual use since 1970, with historical data
going back to the introduction of standard time.
=head1 METHODS
=cut
=head2 ical_entry_type
Returns C<STANDARD>, its iCalendar entry name.
=cut
sub ical_entry_type {'STANDARD'}
=head2 mandatory_unique_properties
According to the iCalendar standard, the following properties must be specified
exactly one time in a standard time declaration:
dtstart tzoffsetto tzoffsetfrom
=cut
sub mandatory_unique_properties {
qw(
dtstart
tzoffsetto
tzoffsetfrom
);
}
=head2 optional_repeatable_properties
According to the iCalendar standard, the following properties may be specified
any number of times for a standard time declaration:
comment rdate rrule tzname
=cut
sub optional_repeatable_properties {
qw(
comment
rdate
rrule
tzname
);
}
=head1 AUTHOR
Jesse Vincent C<< <jesse@bestpractical.com> >> with David Glasser and Simon Wistow
=head1 LICENCE AND COPYRIGHT
Copyright (c) 2005, Best Practical Solutions, LLC. All rights reserved.
This module is free software; you can redistribute it and/or
modify it under the same terms as Perl itself. See L<perlartistic>.
=head1 DISCLAIMER OF WARRANTY
BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER
EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE
ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH
YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL
NECESSARY SERVICING, REPAIR, OR CORRECTION.
IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
REDISTRIBUTE THE SOFTWARE AS PERMITTED BY THE ABOVE LICENCE, BE
LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL,
OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE
THE SOFTWARE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
FAILURE OF THE SOFTWARE TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF
SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
SUCH DAMAGES.
=cut
1;
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