A value object representing a time zone. A time zone is simply a named offset (in seconds) from GMT. Note that two time zone objects are only equivalent if they have both the same offset, and the same name.

A TimeZone instance may be used to convert a Time value to the corresponding time zone.

The class also includes all, which returns a list of all TimeZone objects.

Methods
Included Modules
Constants
US_ZONES = /US|Arizona|Indiana|Hawaii|Alaska/ unless defined?(US_ZONES)
  A regular expression that matches the names of all time zones in the USA.
Attributes
[R] name
[R] utc_offset
Public Class methods
[](arg)

Locate a specific time zone object. If the argument is a string, it is interpreted to mean the name of the timezone to locate. If it is a numeric value it is either the hour offset, or the second offset, of the timezone to find. (The first one with that offset will be returned.) Returns nil if no such time zone is known to the system.

     # File vendor/rails/activesupport/lib/active_support/values/time_zone.rb, line 158
158:     def [](arg)
159:       case arg
160:         when String
161:           all.find { |z| z.name == arg }
162:         when Numeric
163:           arg *= 3600 if arg.abs <= 13
164:           all.find { |z| z.utc_offset == arg.to_i }
165:         else
166:           raise ArgumentError, "invalid argument to TimeZone[]: #{arg.inspect}"
167:       end
168:     end
all()

Return an array of all TimeZone objects. There are multiple TimeZone objects per time zone, in many cases, to make it easier for users to find their own time zone.

     # File vendor/rails/activesupport/lib/active_support/values/time_zone.rb, line 93
 93:     def all
 94:       unless @@zones
 95:         @@zones = []
 96:         [[-43_200, "International Date Line West" ],
 97:          [-39_600, "Midway Island", "Samoa" ],
 98:          [-36_000, "Hawaii" ],
 99:          [-32_400, "Alaska" ],
100:          [-28_800, "Pacific Time (US & Canada)", "Tijuana" ],
101:          [-25_200, "Mountain Time (US & Canada)", "Chihuahua", "La Paz",
102:                    "Mazatlan", "Arizona" ],
103:          [-21_600, "Central Time (US & Canada)", "Saskatchewan", "Guadalajara",
104:                    "Mexico City", "Monterrey", "Central America" ],
105:          [-18_000, "Eastern Time (US & Canada)", "Indiana (East)", "Bogota",
106:                    "Lima", "Quito" ],
107:          [-14_400, "Atlantic Time (Canada)", "Caracas", "La Paz", "Santiago" ],
108:          [-12_600, "Newfoundland" ],
109:          [-10_800, "Brasilia", "Buenos Aires", "Georgetown", "Greenland" ],
110:          [ -7_200, "Mid-Atlantic" ],
111:          [ -3_600, "Azores", "Cape Verde Is." ],
112:          [      0, "Dublin", "Edinburgh", "Lisbon", "London", "Casablanca",
113:                    "Monrovia" ],
114:          [  3_600, "Belgrade", "Bratislava", "Budapest", "Ljubljana", "Prague",
115:                    "Sarajevo", "Skopje", "Warsaw", "Zagreb", "Brussels",
116:                    "Copenhagen", "Madrid", "Paris", "Amsterdam", "Berlin",
117:                    "Bern", "Rome", "Stockholm", "Vienna",
118:                    "West Central Africa" ],
119:          [  7_200, "Bucharest", "Cairo", "Helsinki", "Kyev", "Riga", "Sofia",
120:                    "Tallinn", "Vilnius", "Athens", "Istanbul", "Minsk",
121:                    "Jerusalem", "Harare", "Pretoria" ],
122:          [ 10_800, "Moscow", "St. Petersburg", "Volgograd", "Kuwait", "Riyadh",
123:                    "Nairobi", "Baghdad" ],
124:          [ 12_600, "Tehran" ],
125:          [ 14_400, "Abu Dhabi", "Muscat", "Baku", "Tbilisi", "Yerevan" ],
126:          [ 16_200, "Kabul" ],
127:          [ 18_000, "Ekaterinburg", "Islamabad", "Karachi", "Tashkent" ],
128:          [ 19_800, "Chennai", "Kolkata", "Mumbai", "New Delhi" ],
129:          [ 20_700, "Kathmandu" ],
130:          [ 21_600, "Astana", "Dhaka", "Sri Jayawardenepura", "Almaty",
131:                    "Novosibirsk" ],
132:          [ 23_400, "Rangoon" ],
133:          [ 25_200, "Bangkok", "Hanoi", "Jakarta", "Krasnoyarsk" ],
134:          [ 28_800, "Beijing", "Chongqing", "Hong Kong", "Urumqi",
135:                    "Kuala Lumpur", "Singapore", "Taipei", "Perth", "Irkutsk",
136:                    "Ulaan Bataar" ],
137:          [ 32_400, "Seoul", "Osaka", "Sapporo", "Tokyo", "Yakutsk" ],
138:          [ 34_200, "Darwin", "Adelaide" ],
139:          [ 36_000, "Canberra", "Melbourne", "Sydney", "Brisbane", "Hobart",
140:                    "Vladivostok", "Guam", "Port Moresby" ],
141:          [ 39_600, "Magadan", "Solomon Is.", "New Caledonia" ],
142:          [ 43_200, "Fiji", "Kamchatka", "Marshall Is.", "Auckland",
143:                    "Wellington" ],
144:          [ 46_800, "Nuku'alofa" ]].
145:         each do |offset, *places|
146:           places.each { |place| @@zones << create(place, offset).freeze }
147:         end
148:         @@zones.sort!
149:       end
150:       @@zones
151:     end
create(name, offset)

Create a new TimeZone instance with the given name and offset.

    # File vendor/rails/activesupport/lib/active_support/values/time_zone.rb, line 77
77:     def create(name, offset)
78:       zone = allocate
79:       zone.send :initialize, name, offset
80:       zone
81:     end
new(name, utc_offset)

Create a new TimeZone object with the given name and offset. The offset is the number of seconds that this time zone is offset from UTC (GMT). Seconds were chosen as the offset unit because that is the unit that Ruby uses to represent time zone offsets (see Time#utc_offset).

    # File vendor/rails/activesupport/lib/active_support/values/time_zone.rb, line 18
18:   def initialize(name, utc_offset)
19:     @name = name
20:     @utc_offset = utc_offset
21:   end
new(name)

Return a TimeZone instance with the given name, or nil if no such TimeZone instance exists. (This exists to support the use of this class with the composed_of macro.)

    # File vendor/rails/activesupport/lib/active_support/values/time_zone.rb, line 86
86:     def new(name)
87:       self[name]
88:     end
us_zones()

A convenience method for returning a collection of TimeZone objects for time zones in the USA.

     # File vendor/rails/activesupport/lib/active_support/values/time_zone.rb, line 176
176:     def us_zones
177:       all.find_all { |z| z.name =~ US_ZONES }
178:     end
Public Instance methods
<=>(zone)

Compare this time zone to the parameter. The two are comapred first on their offsets, and then by name.

    # File vendor/rails/activesupport/lib/active_support/values/time_zone.rb, line 62
62:   def <=>(zone)
63:     result = (utc_offset <=> zone.utc_offset)
64:     result = (name <=> zone.name) if result == 0
65:     result
66:   end
adjust(time)

Adjust the given time to the time zone represented by self.

    # File vendor/rails/activesupport/lib/active_support/values/time_zone.rb, line 47
47:   def adjust(time)
48:     time = time.to_time
49:     time + utc_offset - time.utc_offset
50:   end
formatted_offset( colon=true )

Returns the offset of this time zone as a formatted string, of the format "+HH:MM". If the offset is zero, this returns the empty string. If colon is false, a colon will not be inserted into the result.

    # File vendor/rails/activesupport/lib/active_support/values/time_zone.rb, line 27
27:   def formatted_offset( colon=true )
28:     return "" if utc_offset == 0
29:     sign = (utc_offset < 0 ? -1 : 1)
30:     hours = utc_offset.abs / 3600
31:     minutes = (utc_offset.abs % 3600) / 60
32:     "%+03d%s%02d" % [ hours * sign, colon ? ":" : "", minutes ]
33:   end
now()

Compute and return the current time, in the time zone represented by self.

    # File vendor/rails/activesupport/lib/active_support/values/time_zone.rb, line 37
37:   def now
38:     adjust(Time.now)
39:   end
to_s()

Returns a textual representation of this time zone.

    # File vendor/rails/activesupport/lib/active_support/values/time_zone.rb, line 69
69:   def to_s
70:     "(GMT#{formatted_offset}) #{name}"
71:   end
today()

Return the current date in this time zone.

    # File vendor/rails/activesupport/lib/active_support/values/time_zone.rb, line 42
42:   def today
43:     now.to_date
44:   end
unadjust(time)

Reinterprets the given time value as a time in the current time zone, and then adjusts it to return the corresponding time in the local time zone.

    # File vendor/rails/activesupport/lib/active_support/values/time_zone.rb, line 55
55:   def unadjust(time)
56:     time = Time.local(*time.to_time.to_a)
57:     time - utc_offset + time.utc_offset
58:   end