timex

v3.2.0

timex v3.2.0 Timex.TimezoneInfo View Source

All relevant timezone information for a given period, i.e. Europe/Moscow on March 3rd, 2013

Notes:

  • full_name is the name of the zone, but does not indicate anything about the current period (i.e. CST vs CDT)
  • abbreviation is the abbreviated name for the zone in the current period, i.e. “America/Chicago” on 3/30/15 is “CDT”
  • offset_std is the offset in minutes from standard time for this period
  • offset_utc is the offset in minutes from UTC for this period Spec:
  • day_of_week: :sunday, :monday, :tuesday, etc
  • datetime: {{year, month, day}, {hour, minute, second}}
  • from: :min | {day_of_week, datetime}, when this zone starts
  • until: :max | {day_of_week, datetime}, when this zone ends

Link to this section Summary

Types

datetime()
day_of_week()
from_constraint()
offset()
t()
until_constraint()

Functions

create(name, abbr, offset_utc, offset_std, from, until)

Create a custom timezone if a built-in one does not meet your needs

Link to this section Types

Link to this type datetime() View Source 
datetime() :: {{non_neg_integer(), 1..12, 1..31}, {0..24, 0..59, 0..60}}
Link to this type day_of_week() View Source 
day_of_week() ::
  :sunday | :monday | :tuesday | :wednesday | :thursday | :friday | :saturday
Link to this type from_constraint() View Source 
from_constraint() :: :min | {day_of_week(), datetime()}
Link to this type offset() View Source 
offset() :: -85399..85399
Link to this type t() View Source 
t() :: %Timex.TimezoneInfo{
  abbreviation: String.t(),
  from: from_constraint(),
  full_name: String.t(),
  offset_std: offset(),
  offset_utc: offset(),
  until: until_constraint()
}
Link to this type until_constraint() View Source 
until_constraint() :: :max | {day_of_week(), datetime()}

Link to this section Functions

Link to this function create(name, abbr, offset_utc, offset_std, from, until) View Source 
create(
  String.t(),
  String.t(),
  offset(),
  offset(),
  from_constraint(),
  until_constraint()
) :: Timex.TimezoneInfo.t() | {:error, String.t()}

Create a custom timezone if a built-in one does not meet your needs.

You must provide the name, abbreviation, offset from UTC, daylight savings time offset, and the from/until reference points for when the zone takes effect and ends.

To clarify the two offsets, offset_utc is the absolute offset relative to UTC, offset_std is the offset to apply to offset_utc which gives us the offset from UTC during daylight savings time for this timezone. If DST does not apply for this zone, simply set it to 0.

The from/until reference points must meet the following criteria:

- Be set to `:min` for from, or `:max` for until, which represent
  "infinity" for the start/end of the zone period.
- OR, be a tuple of {day_of_week, datetime}, where:
  - `day_of_week` is an atom like `:sunday`
  - `datetime` is an Erlang datetime tuple, e.g. `{{2016,10,8},{2,0,0}}`

IMPORTANT: Offsets are in seconds, not minutes, if you do not ensure they

         are in the correct unit, runtime errors or incorrect results are probable.

Examples 

iex> Elixir.Timex.TimezoneInfo.create("Etc/Test", "TST", 120*60, 0, :min, :max)
%TimezoneInfo{full_name: "Etc/Test", abbreviation: "TST", offset_std: 7200, offset_utc: 0, from: :min, until: :max}
...> Elixir.Timex.TimezoneInfo.create("Etc/Test", "TST", 24*60*60, 0, :min, :max)
{:error, "invalid timezone offset '86400'"}