class ActiveModel::Type::Time

end
attribute :start, :time, precision: 4
include ActiveModel::Attributes
class Event
attribute:
The degree of sub-second precision can be customized when declaring an
event.start # => 1999-12-31 21:01:02 UTC
event.start = “00:01:02+03:00”
Partial time-only formats are also accepted.
event.start # => 2000-01-01 07:23:45 UTC
event.start.class # => Time
event.start = “2004-10-25T01:23:45-06:00”
event = Event.new
normalized to have a date of 2000-01-01 and be in the UTC time zone.
String values are parsed using the ISO 8601 datetime format, but are
end
attribute :start, :time
include ActiveModel::Attributes
class Event
:time key.
Attribute type for time of day representation. It is registered under the
= Active Model Time Type

def cast_value(value) 

def cast_value(value)
  return apply_seconds_precision(value) unless value.is_a?(::String)
  return if value.blank?
  dummy_time_value = value.sub(/\A\d{4}-\d\d-\d\d(?:T|\s)|/, "2000-01-01 ")
  fast_string_to_time(dummy_time_value) || begin
    time_hash = begin
      ::Date._parse(dummy_time_value)
    rescue ArgumentError
    end
    return if time_hash.nil? || time_hash[:hour].nil?
    new_time(*time_hash.values_at(:year, :mon, :mday, :hour, :min, :sec, :sec_fraction, :offset))
  end
end

def type 

def type
  :time
end

def user_input_in_time_zone(value) 

def user_input_in_time_zone(value)
  return unless value.present?
  case value
  when ::String
    value = "2000-01-01 #{value}"
    time_hash = begin
      ::Date._parse(value)
    rescue ArgumentError
    end
    return if time_hash.nil? || time_hash[:hour].nil?
  when ::Time
    value = value.change(year: 2000, day: 1, month: 1)
  end
  super(value)
end