1Data::ICal::Entry::TimeUZsoenre:C:oDnatyrliibguhtte(d3D)Paetral::DIoCcaulm:e:nEtnattriyo:n:TimeZone::Daylight(3)
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NAME

6       Data::ICal::Entry::TimeZone::Daylight - Represents a Daylight Time base
7       offset from UTC for parent TimeZone
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DESCRIPTION

10       A time zone is unambiguously defined by the set of time measurement
11       rules determined by the governing body for a given geographic area.
12       These rules describe at a minimum the base offset from UTC for the time
13       zone, often referred to as the Standard Time offset. Many locations
14       adjust their Standard Time forward or backward by one hour, in order to
15       accommodate seasonal changes in number of daylight hours, often
16       referred to as Daylight Saving Time. Some locations adjust their time
17       by a fraction of an hour. Standard Time is also known as Winter Time.
18       Daylight Saving Time is also known as Advanced Time, Summer Time, or
19       Legal Time in certain countries. The following table shows the changes
20       in time zone rules in effect for New York City starting from 1967. Each
21       line represents a description or rule for a particular observance.
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23            Effective Observance Rule
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25            Date       (Date/Time)             Offset  Abbreviation
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27            1967-*     last Sun in Oct, 02:00  -0500   EST
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29            1967-1973  last Sun in Apr, 02:00  -0400   EDT
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31            1974-1974  Jan 6,  02:00           -0400   EDT
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33            1975-1975  Feb 23, 02:00           -0400   EDT
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35            1976-1986  last Sun in Apr, 02:00  -0400   EDT
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37            1987-*     first Sun in Apr, 02:00 -0400   EDT
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39       Note: The specification of a global time zone registry is not addressed
40       by this document and is left for future study.  However, implementers
41       may find the Olson time zone database [TZ] a useful reference. It is an
42       informal, public-domain collection of time zone information, which is
43       currently being maintained by volunteer Internet participants, and is
44       used in several operating systems. This database contains current and
45       historical time zone information for a wide variety of locations around
46       the globe; it provides a time zone identifier for every unique time
47       zone rule set in actual use since 1970, with historical data going back
48       to the introduction of standard time.
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METHODS

51   ical_entry_type
52       Returns "DAYLIGHT", its iCalendar entry name.
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54   mandatory_unique_properties
55       According to the iCalendar standard, the following properties must be
56       specified exactly one time in a daylight declaration:
57
58               dtstart  tzoffsetto  tzoffsetfrom
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60   optional_repeatable_properties
61       According to the iCalendar standard, the following properties may be
62       specified any number of times for a daylight declaration:
63
64               comment  rdate  rrule  tzname
65

AUTHOR

67       Best Practical Solutions, LLC <modules@bestpractical.com>
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70       Copyright (c) 2005 - 2020, Best Practical Solutions, LLC.  All rights
71       reserved.
72
73       This module is free software; you can redistribute it and/or modify it
74       under the same terms as Perl itself. See perlartistic.
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78perl v5.36.0                      2023-D0a1t-a2:0:ICal::Entry::TimeZone::Daylight(3)
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