Methods
#
A
B
C
D
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F
I
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Y
Z
Constants
COMMON_YEAR_DAYS_IN_MONTH = [nil, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
 
DAYS_INTO_WEEK = { :monday => 0, :tuesday => 1, :wednesday => 2, :thursday => 3, :friday => 4, :saturday => 5, :sunday => 6 }
 
DATE_FORMATS = { :db => "%Y-%m-%d %H:%M:%S", :number => "%Y%m%d%H%M%S", :time => "%H:%M", :short => "%d %b %H:%M", :long => "%B %d, %Y %H:%M", :long_ordinal => lambda { |time| time.strftime("%B #{ActiveSupport::Inflector.ordinalize(time.day)}, %Y %H:%M") }, :rfc822 => lambda { |time| time.strftime("%a, %d %b %Y %H:%M:%S #{time.formatted_offset(false)}") } }
 
Attributes
[RW] zone_default
Instance Public methods
<=>(other)
Also aliased as: compare_without_coercion
===(other)

Overriding case equality method so that it returns true for ActiveSupport::TimeWithZone instances

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 12
def ===(other)
  super || (self == Time && other.is_a?(ActiveSupport::TimeWithZone))
end
_dump(*args)
# File activesupport/lib/active_support/core_ext/time/marshal.rb, line 20
def _dump(*args)
  obj = dup
  obj.instance_variable_set('@marshal_with_utc_coercion', utc?)
  obj.send :_dump_without_utc_flag, *args
end
_dump_without_utc_flag(*args)
Alias for: _dump
_dump_without_zone(*args)
Alias for: _dump
_load(marshaled_time)
# File activesupport/lib/active_support/core_ext/time/marshal.rb, line 8
def _load(marshaled_time)
  time = _load_without_utc_flag(marshaled_time)
  time.instance_eval do
    if defined?(@marshal_with_utc_coercion)
      val = remove_instance_variable("@marshal_with_utc_coercion")
    end
    val ? utc : self
  end
end
acts_like_time?()

Duck-types as a Time-like class. See Object#acts_like?.

# File activesupport/lib/active_support/core_ext/time/acts_like.rb, line 5
def acts_like_time?
  true
end
advance(options)

Uses Date to provide precise Time calculations for years, months, and days. The optionsparameter takes a hash with any of these keys: :years, :months, :weeks, :days, :hours, :minutes, :seconds.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 107
def advance(options)
  unless options[:weeks].nil?
    options[:weeks], partial_weeks = options[:weeks].divmod(1)
    options[:days] = (options[:days] || 0) + 7 * partial_weeks
  end

  unless options[:days].nil?
    options[:days], partial_days = options[:days].divmod(1)
    options[:hours] = (options[:hours] || 0) + 24 * partial_days
  end

  d = to_date.advance(options)
  time_advanced_by_date = change(:year => d.year, :month => d.month, :day => d.day)
  seconds_to_advance = (options[:seconds] || 0) + (options[:minutes] || 0) * 60 + (options[:hours] || 0) * 3600
  seconds_to_advance == 0 ? time_advanced_by_date : time_advanced_by_date.since(seconds_to_advance)
end
ago(seconds)

Returns a new Time representing the time a number of seconds ago, this is basically a wrapper around the Numeric extension

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 125
def ago(seconds)
  since(-seconds)
end
all_day()

Returns a Range representing the whole day of the current time.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 301
def all_day
  beginning_of_day..end_of_day
end
all_month()

Returns a Range representing the whole month of the current time.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 311
def all_month
  beginning_of_month..end_of_month
end
all_quarter()

Returns a Range representing the whole quarter of the current time.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 316
def all_quarter
  beginning_of_quarter..end_of_quarter
end
all_week(start_day = :monday)

Returns a Range representing the whole week of the current time. Week starts on start_day (default is :monday, i.e. end of Sunday).

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 306
def all_week(start_day = :monday)
  beginning_of_week(start_day)..end_of_week(start_day)
end
all_year()

Returns a Range representing the whole year of the current time.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 321
def all_year
  beginning_of_year..end_of_year
end
at_beginning_of_day()
Alias for: beginning_of_day
at_beginning_of_hour()
Alias for: beginning_of_hour
at_beginning_of_month()
Alias for: beginning_of_month
at_beginning_of_quarter()
at_beginning_of_week(start_day = :monday)
Alias for: beginning_of_week
at_beginning_of_year()
Alias for: beginning_of_year
at_end_of_month()
Alias for: end_of_month
at_end_of_quarter()
Alias for: end_of_quarter
at_end_of_week(start_day = :monday)
Alias for: end_of_week
at_end_of_year()
Alias for: end_of_year
at_midnight()
Alias for: beginning_of_day
at_with_coercion(*args)

Layers additional behavior on Time.at so that ActiveSupport::TimeWithZone and DateTime instances can be used when called with a single argument

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 51
def at_with_coercion(*args)
  return at_without_coercion(*args) if args.size != 1

  # Time.at can be called with a time or numerical value
  time_or_number = args.first

  if time_or_number.is_a?(ActiveSupport::TimeWithZone) || time_or_number.is_a?(DateTime)
    at_without_coercion(time_or_number.to_f).getlocal
  else
    at_without_coercion(time_or_number)
  end
end
beginning_of_day()

Returns a new Time representing the start of the day (0:00)

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 227
def beginning_of_day
  #(self - seconds_since_midnight).change(:usec => 0)
  change(:hour => 0)
end
beginning_of_hour()

Returns a new Time representing the start of the hour (x:00)

Also aliased as: at_beginning_of_hour
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 241
def beginning_of_hour
  change(:min => 0)
end
beginning_of_month()

Returns a new Time representing the start of the month (1st of the month, 0:00)

Also aliased as: at_beginning_of_month
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 252
def beginning_of_month
  #self - ((self.mday-1).days + self.seconds_since_midnight)
  change(:day => 1, :hour => 0)
end
beginning_of_quarter()

Returns a new Time representing the start of the quarter (1st of january, april, july, october, 0:00)

Also aliased as: at_beginning_of_quarter
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 267
def beginning_of_quarter
  beginning_of_month.change(:month => [10, 7, 4, 1].detect { |m| m <= month })
end
beginning_of_week(start_day = :monday)

Returns a new Time representing the “start” of this week, week starts on start_day (default is :monday, i.e. Monday, 0:00).

Also aliased as: at_beginning_of_week
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 191
def beginning_of_week(start_day = :monday)
  days_to_start = days_to_week_start(start_day)
  (self - days_to_start.days).midnight
end
beginning_of_year()

Returns a new Time representing the start of the year (1st of january, 0:00)

Also aliased as: at_beginning_of_year
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 279
def beginning_of_year
  change(:month => 1, :day => 1, :hour => 0)
end
change(options)

Returns a new Time where one or more of the elements have been changed according to the optionsparameter. The time options (hour, min, sec, usec) reset cascadingly, so if only the hour is passed, then minute, sec, and usec is set to 0. If the hour and minute is passed, then sec and usec is set to 0.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 90
def change(options)
  ::Time.send(
    utc? ? :utc_time : :local_time,
    options[:year]  || year,
    options[:month] || month,
    options[:day]   || day,
    options[:hour]  || hour,
    options[:min]   || (options[:hour] ? 0 : min),
    options[:sec]   || ((options[:hour] || options[:min]) ? 0 : sec),
    options[:usec]  || ((options[:hour] || options[:min] || options[:sec]) ? 0 : usec)
  )
end
compare_with_coercion(other)

Layers additional behavior on Time#<=> so that DateTime and ActiveSupport::TimeWithZone instances can be chronologically compared with a Time

Also aliased as: <=>
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 357
def compare_with_coercion(other)
  # we're avoiding Time#to_datetime cause it's expensive
  other.is_a?(Time) ? compare_without_coercion(other.to_time) : to_datetime <=> other
end
compare_without_coercion(other)
Alias for: <=>
current()

Returns Time.zone.nowwhen Time.zoneor config.time_zoneare set, otherwise just returns Time.now.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 45
def current
  ::Time.zone ? ::Time.zone.now : ::Time.now
end
days_in_month(month, year = now.year)

Return the number of days in the given month. If no year is specified, it will use the current year.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 18
def days_in_month(month, year = now.year)
  return 29 if month == 2 && ::Date.gregorian_leap?(year)
  COMMON_YEAR_DAYS_IN_MONTH[month]
end
days_to_week_start(start_day = :monday)

Returns number of days to start of this week, week starts on start_day (default is :monday).

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 183
def days_to_week_start(start_day = :monday)
  start_day_number = DAYS_INTO_WEEK[start_day]
  current_day_number = wday != 0 ? wday - 1 : 6
  days_span = current_day_number - start_day_number
  days_span >= 0 ? days_span : 7 + days_span
end
end_of_day()

Returns a new Time representing the end of the day, 23:59:59.999999 (.999999999 in ruby1.9)

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 236
def end_of_day
  change(:hour => 23, :min => 59, :sec => 59, :usec => Rational(999999999, 1000))
end
end_of_hour()

Returns a new Time representing the end of the hour, x:59:59.999999 (.999999999 in ruby1.9)

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 247
def end_of_hour
  change(:min => 59, :sec => 59, :usec => Rational(999999999, 1000))
end
end_of_month()

Returns a new Time representing the end of the month (end of the last day of the month)

Also aliased as: at_end_of_month
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 259
def end_of_month
  #self - ((self.mday-1).days + self.seconds_since_midnight)
  last_day = ::Time.days_in_month(month, year)
  change(:day => last_day, :hour => 23, :min => 59, :sec => 59, :usec => Rational(999999999, 1000))
end
end_of_quarter()

Returns a new Time representing the end of the quarter (end of the last day of march, june, september, december)

Also aliased as: at_end_of_quarter
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 273
def end_of_quarter
  beginning_of_month.change(:month => [3, 6, 9, 12].detect { |m| m >= month }).end_of_month
end
end_of_week(start_day = :monday)

Returns a new Time representing the end of this week, week starts on start_day (default is :monday, i.e. end of Sunday).

Also aliased as: at_end_of_week
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 204
def end_of_week(start_day = :monday)
  days_to_end =  6 - days_to_week_start(start_day)
  (self + days_to_end.days).end_of_day
end
end_of_year()

Returns a new Time representing the end of the year (end of the 31st of december)

Also aliased as: at_end_of_year
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 285
def end_of_year
  change(:month => 12, :day => 31, :hour => 23, :min => 59, :sec => 59, :usec => Rational(999999999, 1000))
end
eql?(other)
Also aliased as: eql_without_coercion
Alias for: eql_with_coercion
eql_with_coercion(other)

Layers additional behavior on #eql? so that ActiveSupport::TimeWithZone instances can be eql? to an equivalent Time

Also aliased as: eql?
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 366
def eql_with_coercion(other)
  # if other is an ActiveSupport::TimeWithZone, coerce a Time instance from it so we can do eql? comparison
  other = other.comparable_time if other.respond_to?(:comparable_time)
  eql_without_coercion(other)
end
eql_without_coercion(other)
Alias for: eql?
find_zone(time_zone)
# File activesupport/lib/active_support/core_ext/time/zones.rb, line 64
def find_zone(time_zone)
  find_zone!(time_zone) rescue nil
end
find_zone!(time_zone)

Returns a TimeZone instance or nil, or raises an ArgumentError for invalid timezones.

# File activesupport/lib/active_support/core_ext/time/zones.rb, line 52
def find_zone!(time_zone)
  return time_zone if time_zone.nil? || time_zone.is_a?(ActiveSupport::TimeZone)
  # lookup timezone based on identifier (unless we've been passed a TZInfo::Timezone)
  unless time_zone.respond_to?(:period_for_local)
    time_zone = ActiveSupport::TimeZone[time_zone] || TZInfo::Timezone.get(time_zone)
  end
  # Return if a TimeZone instance, or wrap in a TimeZone instance if a TZInfo::Timezone
  time_zone.is_a?(ActiveSupport::TimeZone) ? time_zone : ActiveSupport::TimeZone.create(time_zone.name, nil, time_zone)
rescue TZInfo::InvalidTimezoneIdentifier
  raise ArgumentError, "Invalid Timezone: #{time_zone}"
end
formatted_offset(colon = true, alternate_utc_string = nil)

Returns the UTC offset as an +HH:MM formatted string.

Time.local(2000).formatted_offset         # => "-06:00"
Time.local(2000).formatted_offset(false)  # => "-0600"
# File activesupport/lib/active_support/core_ext/time/conversions.rb, line 56
def formatted_offset(colon = true, alternate_utc_string = nil)
  utc? && alternate_utc_string || ActiveSupport::TimeZone.seconds_to_utc_offset(utc_offset, colon)
end
future?()

Tells whether the Time object's time lies in the future

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 78
def future?
  self > ::Time.current
end
in(seconds)
Alias for: since
in_time_zone(zone = ::Time.zone)

Returns the simultaneous time in Time.zone.

Time.zone = 'Hawaii'         # => 'Hawaii'
Time.utc(2000).in_time_zone  # => Fri, 31 Dec 1999 14:00:00 HST -10:00

This method is similar to Time#localtime, except that it uses Time.zoneas the local zone instead of the operating system's time zone.

You can also pass in a TimeZone instance or string that identifies a TimeZone as an argument, and the conversion will be based on that zone instead of Time.zone.

Time.utc(2000).in_time_zone('Alaska')  # => Fri, 31 Dec 1999 15:00:00 AKST -09:00
# File activesupport/lib/active_support/core_ext/time/zones.rb, line 81
def in_time_zone(zone = ::Time.zone)
  return self unless zone

  ActiveSupport::TimeWithZone.new(utc? ? self : getutc, ::Time.find_zone!(zone))
end
local_time(*args)

Wraps class method time_with_datetime_fallbackwith utc_or_localset to :local.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 40
def local_time(*args)
  time_with_datetime_fallback(:local, *args)
end
midnight()
Alias for: beginning_of_day
minus_with_coercion(other)

Time#- can also be used to determine the number of seconds between two Time instances. We're layering on additional behavior so that ActiveSupport::TimeWithZone instances are coerced into values that Time#- will recognize

Also aliased as: -
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 348
def minus_with_coercion(other)
  other = other.comparable_time if other.respond_to?(:comparable_time)
  other.is_a?(DateTime) ? to_f - other.to_f : minus_without_coercion(other)
end
minus_without_coercion(other)
Alias for: -
minus_without_duration(other)
Alias for: -
monday()

Returns a new Date/ DateTimerepresenting the start of this week. Week is assumed to start on a Monday. DateTimeobjects have their time set to 0:00.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 199
def monday
  beginning_of_week
end
months_ago(months)

Returns a new Time representing the time a number of specified months ago

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 143
def months_ago(months)
  advance(:months => -months)
end
months_since(months)

Returns a new Time representing the time a number of specified months in the future

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 148
def months_since(months)
  advance(:months => months)
end
next_month()

Short-hand for #months_since(1)

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 178
def next_month
  months_since(1)
end
next_week(day = :monday)

Returns a new Time representing the start of the given day in next week (default is :monday).

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 222
def next_week(day = :monday)
  since(1.week).beginning_of_week.since(DAYS_INTO_WEEK[day].day).change(:hour => 0)
end
next_year()

Short-hand for #years_since(1)

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 168
def next_year
  years_since(1)
end
past?()

Tells whether the Time object's time lies in the past

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 68
def past?
  self < ::Time.current
end
prev_month()

Short-hand for #months_ago(1)

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 173
def prev_month
  months_ago(1)
end
prev_week(day = :monday)

Returns a new Time representing the start of the given day in the previous week (default is :monday).

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 217
def prev_week(day = :monday)
  ago(1.week).beginning_of_week.since(DAYS_INTO_WEEK[day].day).change(:hour => 0)
end
prev_year()

Short-hand for #years_ago(1)

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 163
def prev_year
  years_ago(1)
end
seconds_since_midnight()

Seconds since midnight: Time.now.seconds_since_midnight

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 83
def seconds_since_midnight
  to_i - change(:hour => 0).to_i + (usec / 1.0e+6)
end
since(seconds)

Returns a new Time representing the time a number of seconds since the instance time

Also aliased as: in
# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 130
def since(seconds)
  self + seconds
rescue
  to_datetime.since(seconds)
end
sunday()

Returns a new Date/ DateTimerepresenting the end of this week. Week is assumed to start on a Monday. DateTime objects have their time set to 23:59:59.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 212
def sunday
  end_of_week
end
time_with_datetime_fallback(utc_or_local, year, month=1, day=1, hour=0, min=0, sec=0, usec=0)

Returns a new Time if requested year can be accommodated by Ruby's Time class (i.e., if year is within either 1970..2038 or 1902..2038, depending on system architecture); otherwise returns a DateTime.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 26
def time_with_datetime_fallback(utc_or_local, year, month=1, day=1, hour=0, min=0, sec=0, usec=0)
  time = ::Time.send(utc_or_local, year, month, day, hour, min, sec, usec)
  # This check is needed because Time.utc(y) returns a time object in the 2000s for 0 <= y <= 138.
  time.year == year ? time : ::DateTime.civil_from_format(utc_or_local, year, month, day, hour, min, sec)
rescue
  ::DateTime.civil_from_format(utc_or_local, year, month, day, hour, min, sec)
end
to_date()

Converts a Time object to a Date, dropping hour, minute, and second precision.

my_time = Time.now  # => Mon Nov 12 22:59:51 -0500 2007
my_time.to_date     # => Mon, 12 Nov 2007

your_time = Time.parse("1/13/2009 1:13:03 P.M.")  # => Tue Jan 13 13:13:03 -0500 2009
your_time.to_date                                 # => Tue, 13 Jan 2009
# File activesupport/lib/active_support/core_ext/time/conversions.rb, line 67
def to_date
  ::Date.new(year, month, day)
end
to_datetime()

Converts a Time instance to a Ruby DateTime instance, preserving UTC offset.

my_time = Time.now    # => Mon Nov 12 23:04:21 -0500 2007
my_time.to_datetime   # => Mon, 12 Nov 2007 23:04:21 -0500

your_time = Time.parse("1/13/2009 1:13:03 P.M.")  # => Tue Jan 13 13:13:03 -0500 2009
your_time.to_datetime                             # => Tue, 13 Jan 2009 13:13:03 -0500
# File activesupport/lib/active_support/core_ext/time/conversions.rb, line 84
def to_datetime
  ::DateTime.civil(year, month, day, hour, min, sec, Rational(utc_offset, 86400))
end
to_default_s(format = :default)
Alias for: to_s
to_formatted_s(format = :default)

Converts to a formatted string. See DATE_FORMATS for builtin formats.

This method is aliased to to_s.

time = Time.now                     # => Thu Jan 18 06:10:17 CST 2007

time.to_formatted_s(:time)          # => "06:10"
time.to_s(:time)                    # => "06:10"

time.to_formatted_s(:db)            # => "2007-01-18 06:10:17"
time.to_formatted_s(:number)        # => "20070118061017"
time.to_formatted_s(:short)         # => "18 Jan 06:10"
time.to_formatted_s(:long)          # => "January 18, 2007 06:10"
time.to_formatted_s(:long_ordinal)  # => "January 18th, 2007 06:10"
time.to_formatted_s(:rfc822)        # => "Thu, 18 Jan 2007 06:10:17 -0600"

Adding your own time formats to to_formatted_s

You can add your own formats to the Time::DATE_FORMATS hash. Use the format name as the hash key and either a strftime string or Proc instance that takes a time argument as the value.

# config/initializers/time_formats.rb
Time::DATE_FORMATS[:month_and_year] = "%B %Y"
Time::DATE_FORMATS[:short_ordinal] = lambda { |time| time.strftime("%B #{time.day.ordinalize}") }
Also aliased as: to_s
# File activesupport/lib/active_support/core_ext/time/conversions.rb, line 42
def to_formatted_s(format = :default)
  if formatter = DATE_FORMATS[format]
    formatter.respond_to?(:call) ? formatter.call(self).to_s : strftime(formatter)
  else
    to_default_s
  end
end
to_s(format = :default)
Also aliased as: to_default_s
Alias for: to_formatted_s
to_time()

A method to keep Time, Date and DateTime instances interchangeable on conversions. In this case, it simply returns self.

# File activesupport/lib/active_support/core_ext/time/conversions.rb, line 73
def to_time
  self
end
today?()

Tells whether the Time object's time is today

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 73
def today?
  to_date == ::Date.current
end
tomorrow()

Convenience method which returns a new Time representing the time 1 day since the instance time

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 296
def tomorrow
  advance(:days => 1)
end
use_zone(time_zone)

Allows override of Time.zonelocally inside supplied block; resets Time.zoneto existing value when done.

# File activesupport/lib/active_support/core_ext/time/zones.rb, line 41
def use_zone(time_zone)
  new_zone = find_zone!(time_zone)
  begin
    old_zone, ::Time.zone = ::Time.zone, new_zone
    yield
  ensure
    ::Time.zone = old_zone
  end
end
utc_time(*args)

Wraps class method time_with_datetime_fallbackwith utc_or_localset to :utc.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 35
def utc_time(*args)
  time_with_datetime_fallback(:utc, *args)
end
weeks_ago(weeks)

Returns a new Time representing the time a number of specified weeks ago.

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 138
def weeks_ago(weeks)
  advance(:weeks => -weeks)
end
years_ago(years)

Returns a new Time representing the time a number of specified years ago

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 153
def years_ago(years)
  advance(:years => -years)
end
years_since(years)

Returns a new Time representing the time a number of specified years in the future

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 158
def years_since(years)
  advance(:years => years)
end
yesterday()

Convenience method which returns a new Time representing the time 1 day ago

# File activesupport/lib/active_support/core_ext/time/calculations.rb, line 291
def yesterday
  advance(:days => -1)
end
zone()

Returns the TimeZone for the current request, if this has been set (via #zone=). If Time.zone has not been set for the current request, returns the TimeZone specified in config.time_zone.

# File activesupport/lib/active_support/core_ext/time/zones.rb, line 9
def zone
  Thread.current[:time_zone] || zone_default
end
zone=(time_zone)

Sets Time.zoneto a TimeZone object for the current request/thread.

This method accepts any of the following:

  • A Rails TimeZone object.

  • An identifier for a Rails TimeZone object (e.g., “Eastern Time (US & Canada)”, -5.hours).

  • A TZInfo::Timezone object.

  • An identifier for a TZInfo::Timezone object (e.g., “America/New_York”).

Here's an example of how you might set Time.zoneon a per request basis and reset it when the request is done. current_user.time_zonejust needs to return a string identifying the user's preferred time zone:

class ApplicationController < ActionController::Base
  around_filter :set_time_zone

  def set_time_zone
    old_time_zone = Time.zone
    Time.zone = current_user.time_zone if logged_in?
    yield
  ensure
    Time.zone = old_time_zone
  end
end
# File activesupport/lib/active_support/core_ext/time/zones.rb, line 36
def zone=(time_zone)
  Thread.current[:time_zone] = find_zone!(time_zone)
end