View Source Calendar.ISO (Elixir v1.17.0)

The default calendar implementation, a Gregorian calendar following ISO 8601.

This calendar implements a proleptic Gregorian calendar and is therefore compatible with the calendar used in most countries today. The proleptic means the Gregorian rules for leap years are applied for all time, consequently the dates give different results before the year 1583 from when the Gregorian calendar was adopted.

ISO 8601 compliance

The ISO 8601 specification is feature-rich, but allows applications to selectively implement most parts of it. The choices Elixir makes are catalogued below.

Features

The standard library supports a minimal set of possible ISO 8601 features. Specifically, the parser only supports calendar dates and does not support ordinal and week formats. Additionally, it supports parsing ISO 8601 formatted durations, including negative time units and fractional seconds.

By default Elixir only parses extended-formatted date/times. You can opt-in to parse basic-formatted date/times.

NaiveDateTime.to_iso8601/2 and DateTime.to_iso8601/2 allow you to produce either basic or extended formatted strings, and Calendar.strftime/2 allows you to format datetimes however else you desire.

Elixir does not support reduced accuracy formats (for example, a date without the day component) nor decimal precisions in the lowest component (such as 10:01:25,5).

Examples

Elixir expects the extended format by default when parsing:

iex> Calendar.ISO.parse_naive_datetime("2015-01-23T23:50:07")
{:ok, {2015, 1, 23, 23, 50, 7, {0, 0}}}
iex> Calendar.ISO.parse_naive_datetime("20150123T235007")
{:error, :invalid_format}

Parsing can be restricted to basic if desired:

iex> Calendar.ISO.parse_naive_datetime("20150123T235007Z", :basic)
{:ok, {2015, 1, 23, 23, 50, 7, {0, 0}}}
iex> Calendar.ISO.parse_naive_datetime("20150123T235007Z", :extended)
{:error, :invalid_format}

Only calendar dates are supported in parsing; ordinal and week dates are not.

iex> Calendar.ISO.parse_date("2015-04-15")
{:ok, {2015, 4, 15}}
iex> Calendar.ISO.parse_date("2015-105")
{:error, :invalid_format}
iex> Calendar.ISO.parse_date("2015-W16")
{:error, :invalid_format}
iex> Calendar.ISO.parse_date("2015-W016-3")
{:error, :invalid_format}

Years, months, days, hours, minutes, and seconds must be fully specified:

iex> Calendar.ISO.parse_date("2015-04-15")
{:ok, {2015, 4, 15}}
iex> Calendar.ISO.parse_date("2015-04")
{:error, :invalid_format}
iex> Calendar.ISO.parse_date("2015")
{:error, :invalid_format}

iex> Calendar.ISO.parse_time("23:50:07.0123456")
{:ok, {23, 50, 7, {12345, 6}}}
iex> Calendar.ISO.parse_time("23:50:07")
{:ok, {23, 50, 7, {0, 0}}}
iex> Calendar.ISO.parse_time("23:50")
{:error, :invalid_format}
iex> Calendar.ISO.parse_time("23")
{:error, :invalid_format}

Extensions

The parser and formatter adopt one ISO 8601 extension: extended year notation.

This allows dates to be prefixed with a + or - sign, extending the range of expressible years from the default (0000..9999) to -9999..9999. Elixir still restricts years in this format to four digits.

Examples

iex> Calendar.ISO.parse_date("-2015-01-23")
{:ok, {-2015, 1, 23}}
iex> Calendar.ISO.parse_date("+2015-01-23")
{:ok, {2015, 1, 23}}

iex> Calendar.ISO.parse_naive_datetime("-2015-01-23 23:50:07")
{:ok, {-2015, 1, 23, 23, 50, 7, {0, 0}}}
iex> Calendar.ISO.parse_naive_datetime("+2015-01-23 23:50:07")
{:ok, {2015, 1, 23, 23, 50, 7, {0, 0}}}

iex> Calendar.ISO.parse_utc_datetime("-2015-01-23 23:50:07Z")
{:ok, {-2015, 1, 23, 23, 50, 7, {0, 0}}, 0}
iex> Calendar.ISO.parse_utc_datetime("+2015-01-23 23:50:07Z")
{:ok, {2015, 1, 23, 23, 50, 7, {0, 0}}, 0}

Additions

ISO 8601 does not allow a whitespace instead of T as a separator between date and times, both when parsing and formatting. This is a common enough representation, Elixir allows it during parsing.

The formatting of dates in NaiveDateTime.to_iso8601/1 and DateTime.to_iso8601/1 do produce specification-compliant string representations using the T separator.

Examples

iex> Calendar.ISO.parse_naive_datetime("2015-01-23 23:50:07.0123456")
{:ok, {2015, 1, 23, 23, 50, 7, {12345, 6}}}
iex> Calendar.ISO.parse_naive_datetime("2015-01-23T23:50:07.0123456")
{:ok, {2015, 1, 23, 23, 50, 7, {12345, 6}}}

iex> Calendar.ISO.parse_utc_datetime("2015-01-23 23:50:07.0123456Z")
{:ok, {2015, 1, 23, 23, 50, 7, {12345, 6}}, 0}
iex> Calendar.ISO.parse_utc_datetime("2015-01-23T23:50:07.0123456Z")
{:ok, {2015, 1, 23, 23, 50, 7, {12345, 6}}, 0}

Summary

Types

bce()

"Before the Current Era" or "Before the Common Era" (BCE), for those years less than 1.

ce()

The "Current Era" or the "Common Era" (CE) which starts in year 1.

day()

day_of_week()

Integer that represents the day of the week, where 1 is Monday and 7 is Sunday.

day_of_year()

era()

The calendar era.

format()

hour()

microsecond()

Microseconds with stored precision.

minute()

month()

quarter_of_year()

second()

utc_offset()

weekday()

year()

year_of_era()

Functions

date_to_string(year, month, day, format \\ :extended)

Converts the given date into a string.

datetime_to_string(year, month, day, hour, minute, second, microsecond, time_zone, zone_abbr, utc_offset, std_offset, format \\ :extended)

Converts the datetime (with time zone) into a string.

day_of_era(year, month, day)

Calculates the day and era from the given year, month, and day.

day_of_week(year, month, day, starting_on)

Calculates the day of the week from the given year, month, and day.

day_of_year(year, month, day)

Calculates the day of the year from the given year, month, and day.

day_rollover_relative_to_midnight_utc()

See Calendar.day_rollover_relative_to_midnight_utc/0 for documentation.

days_in_month(year, month)

Returns how many days there are in the given year-month.

iso_days_to_beginning_of_day(arg)

Converts the Calendar.iso_days/0 to the first moment of the day.

iso_days_to_end_of_day(arg)

Converts the Calendar.iso_days/0 to the last moment of the day.

leap_year?(year)

Returns if the given year is a leap year.

months_in_year(year)

Returns how many months there are in the given year.

naive_datetime_from_iso_days(arg)

Converts the Calendar.iso_days/0 format to the datetime format specified by this calendar.

naive_datetime_to_iso_days(year, month, day, hour, minute, second, microsecond)

Returns the Calendar.iso_days/0 format of the specified date.

naive_datetime_to_string(year, month, day, hour, minute, second, microsecond, format \\ :extended)

Converts the datetime (without time zone) into a string.

parse_date(string)

Parses a date string in the :extended format.

parse_date(string, format)

Parses a date string according to a given format.

parse_duration(arg1)

Parses an ISO 8601 formatted duration string to a list of Duration compabitble unit pairs.

parse_naive_datetime(string)

Parses a naive datetime string in the :extended format.

parse_naive_datetime(string, format)

Parses a naive datetime string according to a given format.

parse_time(string)

Parses a time string in the :extended format.

parse_time(string, format)

Parses a time string according to a given format.

parse_utc_datetime(string)

Parses a UTC datetime string in the :extended format.

parse_utc_datetime(string, format)

Parses a UTC datetime string according to a given format.

quarter_of_year(year, month, day)

Calculates the quarter of the year from the given year, month, and day.

shift_date(year, month, day, duration)

Shifts Date by Duration according to its calendar.

shift_naive_datetime(year, month, day, hour, minute, second, microsecond, duration)

Shifts NaiveDateTime by Duration according to its calendar.

shift_time(hour, minute, second, microsecond, duration)

Shifts Time by Duration units according to its calendar.

time_from_day_fraction(arg)

Converts a day fraction to this Calendar's representation of time.

time_to_day_fraction(hour, minute, second, arg)

Returns the normalized day fraction of the specified time.

time_to_string(hour, minute, second, microsecond, format \\ :extended)

Converts the given time into a string.

time_unit_to_precision(int)

Converts a System.time_unit/0 to precision.

valid_date?(year, month, day)

Determines if the date given is valid according to the proleptic Gregorian calendar.

valid_time?(hour, minute, second, microsecond)

Determines if the date given is valid according to the proleptic Gregorian calendar.

year_of_era(year)

Calculates the year and era from the given year.

year_of_era(year, month, day)

Calendar callback to compute the year and era from the given year, month and day.

Types

bce()

@type bce() :: 0

"Before the Current Era" or "Before the Common Era" (BCE), for those years less than 1.

ce()

@type ce() :: 1

The "Current Era" or the "Common Era" (CE) which starts in year 1.

day()

@type day() :: 1..31

day_of_week()

@type day_of_week() :: 1..7

Integer that represents the day of the week, where 1 is Monday and 7 is Sunday.

day_of_year()

@type day_of_year() :: 1..366

era()

@type era() :: bce() | ce()

The calendar era.

The ISO calendar has two eras:

CE - which starts in year 1 and is defined as era 1.
BCE - for those years less than 1 and is defined as era 0.

format()

@type format() :: :basic | :extended

hour()

@type hour() :: 0..23

microsecond()

@type microsecond() :: {0..999_999, 0..6}

Microseconds with stored precision.

The precision represents the number of digits that must be used when representing the microseconds to external format. If the precision is 0, it means microseconds must be skipped.

minute()

@type minute() :: 0..59

month()

@type month() :: 1..12

quarter_of_year()

@type quarter_of_year() :: 1..4

second()

@type second() :: 0..59

utc_offset()

@type utc_offset() :: integer()

weekday()

@type weekday() ::
  :monday | :tuesday | :wednesday | :thursday | :friday | :saturday | :sunday

year()

@type year() :: -9999..9999

year_of_era()

@type year_of_era() :: {1..10000, era()}

Functions

date_to_string(year, month, day, format \\ :extended)

(since 1.4.0)

@spec date_to_string(year(), month(), day(), :basic | :extended) :: String.t()

Converts the given date into a string.

By default, returns dates formatted in the "extended" format, for human readability. It also supports the "basic" format by passing the :basic option.

Examples

iex> Calendar.ISO.date_to_string(2015, 2, 28)
"2015-02-28"
iex> Calendar.ISO.date_to_string(2017, 8, 1)
"2017-08-01"
iex> Calendar.ISO.date_to_string(-99, 1, 31)
"-0099-01-31"

iex> Calendar.ISO.date_to_string(2015, 2, 28, :basic)
"20150228"
iex> Calendar.ISO.date_to_string(-99, 1, 31, :basic)
"-00990131"

datetime_to_string(year, month, day, hour, minute, second, microsecond, time_zone, zone_abbr, utc_offset, std_offset, format \\ :extended)

(since 1.4.0)

@spec datetime_to_string(
  year(),
  month(),
  day(),
  Calendar.hour(),
  Calendar.minute(),
  Calendar.second(),
  Calendar.microsecond(),
  Calendar.time_zone(),
  Calendar.zone_abbr(),
  Calendar.utc_offset(),
  Calendar.std_offset(),
  :basic | :extended
) :: String.t()

Converts the datetime (with time zone) into a string.

By default, returns datetimes formatted in the "extended" format, for human readability. It also supports the "basic" format by passing the :basic option.

Examples

iex> time_zone = "Etc/UTC"
iex> Calendar.ISO.datetime_to_string(2017, 8, 1, 1, 2, 3, {4, 5}, time_zone, "UTC", 0, 0)
"2017-08-01 01:02:03.00000Z"
iex> Calendar.ISO.datetime_to_string(2017, 8, 1, 1, 2, 3, {4, 5}, time_zone, "UTC", 3600, 0)
"2017-08-01 01:02:03.00000+01:00"
iex> Calendar.ISO.datetime_to_string(2017, 8, 1, 1, 2, 3, {4, 5}, time_zone, "UTC", 3600, 3600)
"2017-08-01 01:02:03.00000+02:00"

iex> time_zone = "Europe/Berlin"
iex> Calendar.ISO.datetime_to_string(2017, 8, 1, 1, 2, 3, {4, 5}, time_zone, "CET", 3600, 0)
"2017-08-01 01:02:03.00000+01:00 CET Europe/Berlin"
iex> Calendar.ISO.datetime_to_string(2017, 8, 1, 1, 2, 3, {4, 5}, time_zone, "CDT", 3600, 3600)
"2017-08-01 01:02:03.00000+02:00 CDT Europe/Berlin"

iex> time_zone = "America/Los_Angeles"
iex> Calendar.ISO.datetime_to_string(2015, 2, 28, 1, 2, 3, {4, 5}, time_zone, "PST", -28800, 0)
"2015-02-28 01:02:03.00000-08:00 PST America/Los_Angeles"
iex> Calendar.ISO.datetime_to_string(2015, 2, 28, 1, 2, 3, {4, 5}, time_zone, "PDT", -28800, 3600)
"2015-02-28 01:02:03.00000-07:00 PDT America/Los_Angeles"

iex> time_zone = "Europe/Berlin"
iex> Calendar.ISO.datetime_to_string(2017, 8, 1, 1, 2, 3, {4, 5}, time_zone, "CET", 3600, 0, :basic)
"20170801 010203.00000+0100 CET Europe/Berlin"

day_of_era(year, month, day)

(since 1.8.0)

@spec day_of_era(year(), month(), day()) :: Calendar.day_of_era()

Calculates the day and era from the given year, month, and day.

Examples

iex> Calendar.ISO.day_of_era(0, 1, 1)
{366, 0}
iex> Calendar.ISO.day_of_era(1, 1, 1)
{1, 1}
iex> Calendar.ISO.day_of_era(0, 12, 31)
{1, 0}
iex> Calendar.ISO.day_of_era(0, 12, 30)
{2, 0}
iex> Calendar.ISO.day_of_era(-1, 12, 31)
{367, 0}

day_of_week(year, month, day, starting_on)

(since 1.11.0)

@spec day_of_week(year(), month(), day(), :default | weekday()) ::
  {day_of_week(), 1, 7}

Calculates the day of the week from the given year, month, and day.

It is an integer from 1 to 7, where 1 is the given starting_on weekday. For example, if starting_on is set to :monday, then 1 is Monday and 7 is Sunday.

starting_on can also be :default, which is equivalent to :monday.

Examples

iex> Calendar.ISO.day_of_week(2016, 10, 31, :monday)
{1, 1, 7}
iex> Calendar.ISO.day_of_week(2016, 11, 1, :monday)
{2, 1, 7}
iex> Calendar.ISO.day_of_week(2016, 11, 2, :monday)
{3, 1, 7}
iex> Calendar.ISO.day_of_week(2016, 11, 3, :monday)
{4, 1, 7}
iex> Calendar.ISO.day_of_week(2016, 11, 4, :monday)
{5, 1, 7}
iex> Calendar.ISO.day_of_week(2016, 11, 5, :monday)
{6, 1, 7}
iex> Calendar.ISO.day_of_week(2016, 11, 6, :monday)
{7, 1, 7}
iex> Calendar.ISO.day_of_week(-99, 1, 31, :monday)
{4, 1, 7}

iex> Calendar.ISO.day_of_week(2016, 10, 31, :sunday)
{2, 1, 7}
iex> Calendar.ISO.day_of_week(2016, 11, 1, :sunday)
{3, 1, 7}
iex> Calendar.ISO.day_of_week(2016, 11, 2, :sunday)
{4, 1, 7}
iex> Calendar.ISO.day_of_week(2016, 11, 3, :sunday)
{5, 1, 7}
iex> Calendar.ISO.day_of_week(2016, 11, 4, :sunday)
{6, 1, 7}
iex> Calendar.ISO.day_of_week(2016, 11, 5, :sunday)
{7, 1, 7}
iex> Calendar.ISO.day_of_week(2016, 11, 6, :sunday)
{1, 1, 7}
iex> Calendar.ISO.day_of_week(-99, 1, 31, :sunday)
{5, 1, 7}

iex> Calendar.ISO.day_of_week(2016, 10, 31, :saturday)
{3, 1, 7}

day_of_year(year, month, day)

(since 1.8.0)

@spec day_of_year(year(), month(), day()) :: day_of_year()

Calculates the day of the year from the given year, month, and day.

It is an integer from 1 to 366.

Examples

iex> Calendar.ISO.day_of_year(2016, 1, 31)
31
iex> Calendar.ISO.day_of_year(-99, 2, 1)
32
iex> Calendar.ISO.day_of_year(2018, 2, 28)
59

day_rollover_relative_to_midnight_utc()

(since 1.5.0)

@spec day_rollover_relative_to_midnight_utc() :: {0, 1}

See Calendar.day_rollover_relative_to_midnight_utc/0 for documentation.

days_in_month(year, month)

(since 1.4.0)

@spec days_in_month(year(), month()) :: 28..31

Returns how many days there are in the given year-month.

Examples

iex> Calendar.ISO.days_in_month(1900, 1)
31
iex> Calendar.ISO.days_in_month(1900, 2)
28
iex> Calendar.ISO.days_in_month(2000, 2)
29
iex> Calendar.ISO.days_in_month(2001, 2)
28
iex> Calendar.ISO.days_in_month(2004, 2)
29
iex> Calendar.ISO.days_in_month(2004, 4)
30
iex> Calendar.ISO.days_in_month(-1, 5)
31

iso_days_to_beginning_of_day(arg)

(since 1.15.0)

@spec iso_days_to_beginning_of_day(Calendar.iso_days()) :: Calendar.iso_days()

Converts the Calendar.iso_days/0 to the first moment of the day.

Examples

iex> Calendar.ISO.iso_days_to_beginning_of_day({0, {0, 86400000000}})
{0, {0, 86400000000}}
iex> Calendar.ISO.iso_days_to_beginning_of_day({730485, {43200000000, 86400000000}})
{730485, {0, 86400000000}}
iex> Calendar.ISO.iso_days_to_beginning_of_day({730485, {46800000000, 86400000000}})
{730485, {0, 86400000000}}

iso_days_to_end_of_day(arg)

(since 1.15.0)

@spec iso_days_to_end_of_day(Calendar.iso_days()) :: Calendar.iso_days()

Converts the Calendar.iso_days/0 to the last moment of the day.

Examples

iex> Calendar.ISO.iso_days_to_end_of_day({0, {0, 86400000000}})
{0, {86399999999, 86400000000}}
iex> Calendar.ISO.iso_days_to_end_of_day({730485, {43200000000, 86400000000}})
{730485, {86399999999, 86400000000}}
iex> Calendar.ISO.iso_days_to_end_of_day({730485, {46800000000, 86400000000}})
{730485, {86399999999, 86400000000}}

leap_year?(year)

(since 1.3.0)

@spec leap_year?(year()) :: boolean()

Returns if the given year is a leap year.

Examples

iex> Calendar.ISO.leap_year?(2000)
true
iex> Calendar.ISO.leap_year?(2001)
false
iex> Calendar.ISO.leap_year?(2004)
true
iex> Calendar.ISO.leap_year?(1900)
false
iex> Calendar.ISO.leap_year?(-4)
true

months_in_year(year)

(since 1.7.0)

@spec months_in_year(year()) :: 12

Returns how many months there are in the given year.

Example

iex> Calendar.ISO.months_in_year(2004)
12

naive_datetime_from_iso_days(arg)

(since 1.5.0)

@spec naive_datetime_from_iso_days(Calendar.iso_days()) ::
  {Calendar.year(), Calendar.month(), Calendar.day(), Calendar.hour(),
   Calendar.minute(), Calendar.second(), Calendar.microsecond()}

Converts the Calendar.iso_days/0 format to the datetime format specified by this calendar.

Examples

iex> Calendar.ISO.naive_datetime_from_iso_days({0, {0, 86400}})
{0, 1, 1, 0, 0, 0, {0, 6}}
iex> Calendar.ISO.naive_datetime_from_iso_days({730_485, {0, 86400}})
{2000, 1, 1, 0, 0, 0, {0, 6}}
iex> Calendar.ISO.naive_datetime_from_iso_days({730_485, {43200, 86400}})
{2000, 1, 1, 12, 0, 0, {0, 6}}
iex> Calendar.ISO.naive_datetime_from_iso_days({-365, {0, 86400000000}})
{-1, 1, 1, 0, 0, 0, {0, 6}}

naive_datetime_to_iso_days(year, month, day, hour, minute, second, microsecond)

(since 1.5.0)

@spec naive_datetime_to_iso_days(
  Calendar.year(),
  Calendar.month(),
  Calendar.day(),
  Calendar.hour(),
  Calendar.minute(),
  Calendar.second(),
  Calendar.microsecond()
) :: Calendar.iso_days()

Returns the Calendar.iso_days/0 format of the specified date.

Examples

iex> Calendar.ISO.naive_datetime_to_iso_days(0, 1, 1, 0, 0, 0, {0, 6})
{0, {0, 86400000000}}
iex> Calendar.ISO.naive_datetime_to_iso_days(2000, 1, 1, 12, 0, 0, {0, 6})
{730485, {43200000000, 86400000000}}
iex> Calendar.ISO.naive_datetime_to_iso_days(2000, 1, 1, 13, 0, 0, {0, 6})
{730485, {46800000000, 86400000000}}
iex> Calendar.ISO.naive_datetime_to_iso_days(-1, 1, 1, 0, 0, 0, {0, 6})
{-365, {0, 86400000000}}

naive_datetime_to_string(year, month, day, hour, minute, second, microsecond, format \\ :extended)

(since 1.4.0)

@spec naive_datetime_to_string(
  year(),
  month(),
  day(),
  Calendar.hour(),
  Calendar.minute(),
  Calendar.second(),
  Calendar.microsecond(),
  :basic | :extended
) :: String.t()

Converts the datetime (without time zone) into a string.

By default, returns datetimes formatted in the "extended" format, for human readability. It also supports the "basic" format by passing the :basic option.

Examples

iex> Calendar.ISO.naive_datetime_to_string(2015, 2, 28, 1, 2, 3, {4, 6})
"2015-02-28 01:02:03.000004"
iex> Calendar.ISO.naive_datetime_to_string(2017, 8, 1, 1, 2, 3, {4, 5})
"2017-08-01 01:02:03.00000"

iex> Calendar.ISO.naive_datetime_to_string(2015, 2, 28, 1, 2, 3, {4, 6}, :basic)
"20150228 010203.000004"

parse_date(string)

(since 1.10.0)

@spec parse_date(String.t()) :: {:ok, {year(), month(), day()}} | {:error, atom()}

Parses a date string in the :extended format.

For more information on supported strings, see how this module implements ISO 8601.

Examples

iex> Calendar.ISO.parse_date("2015-01-23")
{:ok, {2015, 1, 23}}

iex> Calendar.ISO.parse_date("2015:01:23")
{:error, :invalid_format}
iex> Calendar.ISO.parse_date("2015-01-32")
{:error, :invalid_date}

parse_date(string, format)

(since 1.12.0)

@spec parse_date(String.t(), format()) ::
  {:ok, {year(), month(), day()}} | {:error, atom()}

Parses a date string according to a given format.

The format can either be :basic or :extended.

For more information on supported strings, see how this module implements ISO 8601.

Examples

iex> Calendar.ISO.parse_date("20150123", :basic)
{:ok, {2015, 1, 23}}
iex> Calendar.ISO.parse_date("20150123", :extended)
{:error, :invalid_format}

parse_duration(arg1)

(since 1.17.0)

@spec parse_duration(String.t()) :: {:ok, [Duration.unit_pair()]} | {:error, atom()}

Parses an ISO 8601 formatted duration string to a list of Duration compabitble unit pairs.

See Duration.from_iso8601/1.

parse_naive_datetime(string)

(since 1.10.0)

@spec parse_naive_datetime(String.t()) ::
  {:ok, {year(), month(), day(), hour(), minute(), second(), microsecond()}}
  | {:error, atom()}

Parses a naive datetime string in the :extended format.

For more information on supported strings, see how this module implements ISO 8601.

Examples

iex> Calendar.ISO.parse_naive_datetime("2015-01-23 23:50:07")
{:ok, {2015, 1, 23, 23, 50, 7, {0, 0}}}
iex> Calendar.ISO.parse_naive_datetime("2015-01-23 23:50:07Z")
{:ok, {2015, 1, 23, 23, 50, 7, {0, 0}}}
iex> Calendar.ISO.parse_naive_datetime("2015-01-23 23:50:07-02:30")
{:ok, {2015, 1, 23, 23, 50, 7, {0, 0}}}

iex> Calendar.ISO.parse_naive_datetime("2015-01-23 23:50:07.0")
{:ok, {2015, 1, 23, 23, 50, 7, {0, 1}}}
iex> Calendar.ISO.parse_naive_datetime("2015-01-23 23:50:07,0123456")
{:ok, {2015, 1, 23, 23, 50, 7, {12345, 6}}}

parse_naive_datetime(string, format)

(since 1.12.0)

@spec parse_naive_datetime(String.t(), format()) ::
  {:ok, {year(), month(), day(), hour(), minute(), second(), microsecond()}}
  | {:error, atom()}

Parses a naive datetime string according to a given format.

The format can either be :basic or :extended.

For more information on supported strings, see how this module implements ISO 8601.

Examples

iex> Calendar.ISO.parse_naive_datetime("20150123 235007", :basic)
{:ok, {2015, 1, 23, 23, 50, 7, {0, 0}}}
iex> Calendar.ISO.parse_naive_datetime("20150123 235007", :extended)
{:error, :invalid_format}

parse_time(string)

(since 1.10.0)

@spec parse_time(String.t()) ::
  {:ok, {hour(), minute(), second(), microsecond()}} | {:error, atom()}

Parses a time string in the :extended format.

For more information on supported strings, see how this module implements ISO 8601.

Examples

iex> Calendar.ISO.parse_time("23:50:07")
{:ok, {23, 50, 7, {0, 0}}}

iex> Calendar.ISO.parse_time("23:50:07Z")
{:ok, {23, 50, 7, {0, 0}}}
iex> Calendar.ISO.parse_time("T23:50:07Z")
{:ok, {23, 50, 7, {0, 0}}}

parse_time(string, format)

(since 1.12.0)

@spec parse_time(String.t(), format()) ::
  {:ok, {hour(), minute(), second(), microsecond()}} | {:error, atom()}

Parses a time string according to a given format.

The format can either be :basic or :extended.

For more information on supported strings, see how this module implements ISO 8601.

Examples

iex> Calendar.ISO.parse_time("235007", :basic)
{:ok, {23, 50, 7, {0, 0}}}
iex> Calendar.ISO.parse_time("235007", :extended)
{:error, :invalid_format}

parse_utc_datetime(string)

(since 1.10.0)

@spec parse_utc_datetime(String.t()) ::
  {:ok, {year(), month(), day(), hour(), minute(), second(), microsecond()},
   utc_offset()}
  | {:error, atom()}

Parses a UTC datetime string in the :extended format.

For more information on supported strings, see how this module implements ISO 8601.

Examples

iex> Calendar.ISO.parse_utc_datetime("2015-01-23 23:50:07Z")
{:ok, {2015, 1, 23, 23, 50, 7, {0, 0}}, 0}

iex> Calendar.ISO.parse_utc_datetime("2015-01-23 23:50:07+02:30")
{:ok, {2015, 1, 23, 21, 20, 7, {0, 0}}, 9000}

iex> Calendar.ISO.parse_utc_datetime("2015-01-23 23:50:07")
{:error, :missing_offset}

parse_utc_datetime(string, format)

(since 1.12.0)

@spec parse_utc_datetime(String.t(), format()) ::
  {:ok, {year(), month(), day(), hour(), minute(), second(), microsecond()},
   utc_offset()}
  | {:error, atom()}

Parses a UTC datetime string according to a given format.

The format can either be :basic or :extended.

For more information on supported strings, see how this module implements ISO 8601.

Examples

iex> Calendar.ISO.parse_utc_datetime("20150123 235007Z", :basic)
{:ok, {2015, 1, 23, 23, 50, 7, {0, 0}}, 0}
iex> Calendar.ISO.parse_utc_datetime("20150123 235007Z", :extended)
{:error, :invalid_format}

quarter_of_year(year, month, day)

(since 1.8.0)

@spec quarter_of_year(year(), month(), day()) :: quarter_of_year()

Calculates the quarter of the year from the given year, month, and day.

It is an integer from 1 to 4.

Examples

iex> Calendar.ISO.quarter_of_year(2016, 1, 31)
1
iex> Calendar.ISO.quarter_of_year(2016, 4, 3)
2
iex> Calendar.ISO.quarter_of_year(-99, 9, 31)
3
iex> Calendar.ISO.quarter_of_year(2018, 12, 28)
4

shift_date(year, month, day, duration)

@spec shift_date(year(), month(), day(), Duration.t()) :: {year(), month(), day()}

Shifts Date by Duration according to its calendar.

Examples

iex> Calendar.ISO.shift_date(2016, 1, 3, Duration.new!(month: 2))
{2016, 3, 3}
iex> Calendar.ISO.shift_date(2016, 2, 29, Duration.new!(month: 1))
{2016, 3, 29}
iex> Calendar.ISO.shift_date(2016, 1, 31, Duration.new!(month: 1))
{2016, 2, 29}
iex> Calendar.ISO.shift_date(2016, 1, 31, Duration.new!(year: 4, day: 1))
{2020, 2, 1}

shift_naive_datetime(year, month, day, hour, minute, second, microsecond, duration)

@spec shift_naive_datetime(
  year(),
  month(),
  day(),
  hour(),
  minute(),
  second(),
  microsecond(),
  Duration.t()
) :: {year(), month(), day(), hour(), minute(), second(), microsecond()}

Shifts NaiveDateTime by Duration according to its calendar.

Examples

iex> Calendar.ISO.shift_naive_datetime(2016, 1, 3, 0, 0, 0, {0, 0}, Duration.new!(hour: 1))
{2016, 1, 3, 1, 0, 0, {0, 0}}
iex> Calendar.ISO.shift_naive_datetime(2016, 1, 3, 0, 0, 0, {0, 0}, Duration.new!(hour: 30))
{2016, 1, 4, 6, 0, 0, {0, 0}}
iex> Calendar.ISO.shift_naive_datetime(2016, 1, 3, 0, 0, 0, {0, 0}, Duration.new!(microsecond: {100, 6}))
{2016, 1, 3, 0, 0, 0, {100, 6}}

shift_time(hour, minute, second, microsecond, duration)

@spec shift_time(hour(), minute(), second(), microsecond(), Duration.t()) ::
  {hour(), minute(), second(), microsecond()}

Shifts Time by Duration units according to its calendar.

Examples

iex> Calendar.ISO.shift_time(13, 0, 0, {0, 0}, Duration.new!(hour: 2))
{15, 0, 0, {0, 0}}
iex> Calendar.ISO.shift_time(13, 0, 0, {0, 0}, Duration.new!(microsecond: {100, 6}))
{13, 0, 0, {100, 6}}

time_from_day_fraction(arg)

(since 1.5.0)

@spec time_from_day_fraction(Calendar.day_fraction()) ::
  {hour(), minute(), second(), microsecond()}

Converts a day fraction to this Calendar's representation of time.

Examples

iex> Calendar.ISO.time_from_day_fraction({1, 2})
{12, 0, 0, {0, 6}}
iex> Calendar.ISO.time_from_day_fraction({13, 24})
{13, 0, 0, {0, 6}}

time_to_day_fraction(hour, minute, second, arg)

(since 1.5.0)

@spec time_to_day_fraction(
  Calendar.hour(),
  Calendar.minute(),
  Calendar.second(),
  Calendar.microsecond()
) :: Calendar.day_fraction()

Returns the normalized day fraction of the specified time.

Examples

iex> Calendar.ISO.time_to_day_fraction(0, 0, 0, {0, 6})
{0, 86400000000}
iex> Calendar.ISO.time_to_day_fraction(12, 34, 56, {123, 6})
{45296000123, 86400000000}

time_to_string(hour, minute, second, microsecond, format \\ :extended)

(since 1.5.0)

@spec time_to_string(
  Calendar.hour(),
  Calendar.minute(),
  Calendar.second(),
  Calendar.microsecond(),
  :basic | :extended
) :: String.t()

Converts the given time into a string.

By default, returns times formatted in the "extended" format, for human readability. It also supports the "basic" format by passing the :basic option.

Examples

iex> Calendar.ISO.time_to_string(2, 2, 2, {2, 6})
"02:02:02.000002"
iex> Calendar.ISO.time_to_string(2, 2, 2, {2, 2})
"02:02:02.00"
iex> Calendar.ISO.time_to_string(2, 2, 2, {2, 0})
"02:02:02"

iex> Calendar.ISO.time_to_string(2, 2, 2, {2, 6}, :basic)
"020202.000002"
iex> Calendar.ISO.time_to_string(2, 2, 2, {2, 6}, :extended)
"02:02:02.000002"

time_unit_to_precision(int)

(since 1.15.0)

@spec time_unit_to_precision(System.time_unit()) :: 0..6

Converts a System.time_unit/0 to precision.

Integer-based time units always get maximum precision.

Examples

iex> Calendar.ISO.time_unit_to_precision(:nanosecond)
6

iex> Calendar.ISO.time_unit_to_precision(:second)
0

iex> Calendar.ISO.time_unit_to_precision(1)
6

valid_date?(year, month, day)

(since 1.5.0)

@spec valid_date?(year(), month(), day()) :: boolean()

Determines if the date given is valid according to the proleptic Gregorian calendar.

Examples

iex> Calendar.ISO.valid_date?(2015, 2, 28)
true
iex> Calendar.ISO.valid_date?(2015, 2, 30)
false
iex> Calendar.ISO.valid_date?(-1, 12, 31)
true
iex> Calendar.ISO.valid_date?(-1, 12, 32)
false

valid_time?(hour, minute, second, microsecond)

(since 1.5.0)

@spec valid_time?(
  Calendar.hour(),
  Calendar.minute(),
  Calendar.second(),
  Calendar.microsecond()
) ::
  boolean()

Determines if the date given is valid according to the proleptic Gregorian calendar.

Leap seconds are not supported by the built-in Calendar.ISO.

Examples

iex> Calendar.ISO.valid_time?(10, 50, 25, {3006, 6})
true
iex> Calendar.ISO.valid_time?(23, 59, 60, {0, 0})
false
iex> Calendar.ISO.valid_time?(24, 0, 0, {0, 0})
false

year_of_era(year)

(since 1.8.0)

@spec year_of_era(year()) :: {1..10000, era()}

Calculates the year and era from the given year.

The ISO calendar has two eras: the "current era" (CE) which starts in year 1 and is defined as era 1. And "before the current era" (BCE) for those years less than 1, defined as era 0.

Examples

iex> Calendar.ISO.year_of_era(1)
{1, 1}
iex> Calendar.ISO.year_of_era(2018)
{2018, 1}
iex> Calendar.ISO.year_of_era(0)
{1, 0}
iex> Calendar.ISO.year_of_era(-1)
{2, 0}

year_of_era(year, month, day)

(since 1.13.0)

@spec year_of_era(year(), month(), day()) :: {1..10000, era()}

Calendar callback to compute the year and era from the given year, month and day.

In the ISO calendar, the new year coincides with the new era, so the month and day arguments are discarded. If you only have the year available, you can year_of_era/1 instead.

Examples

iex> Calendar.ISO.year_of_era(1, 1, 1)
{1, 1}
iex> Calendar.ISO.year_of_era(2018, 12, 1)
{2018, 1}
iex> Calendar.ISO.year_of_era(0, 1, 1)
{1, 0}
iex> Calendar.ISO.year_of_era(-1, 12, 1)
{2, 0}