1Data::ICal::Entry::TimeUZsoenre:C:oDnatyrliibguhtte(d3D)Paetral::DIoCcaulm:e:nEtnattriyo:n:TimeZone::Daylight(3)
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6 Data::ICal::Entry::TimeZone::Daylight - Represents a Daylight Time base
7 offset from UTC for parent TimeZone
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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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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:
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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:
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64 comment rdate rrule tzname
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67 Best Practical Solutions, LLC <modules@bestpractical.com>
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70 Copyright (c) 2005 - 2015, Best Practical Solutions, LLC. All rights
71 reserved.
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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 v5.28.0 2015-D0a2t-a1:7:ICal::Entry::TimeZone::Daylight(3)