Time

A Time struct and functions.

The Time struct contains the fields hour, minute, second and microseconds. New times can be built with the new/4 function or using the ~T sigil:

iex> ~T[23:00:07.001]
~T[23:00:07.001]

Both new/4 and sigil return a struct where the time fields can be accessed directly:

iex> time = ~T[23:00:07.001]
iex> time.hour
23
iex> time.microsecond
{1000, 3}

Developers should avoid creating the Time struct directly and instead rely on the functions provided by this module as well as the ones in 3rd party calendar libraries.

Summary

Types

t()

Functions

from_erl(arg, microsecond \\ {0, 0}): Converts an Erlang time tuple to a Time struct
from_erl!(tuple, microsecond \\ {0, 0}): Converts an Erlang time tuple to a Time struct
from_iso8601(arg): Parses the extended “Local time” format described by ISO8601:2004
from_iso8601!(string): Parses the extended “Local time” format described by ISO8601:2004
new(hour, minute, second, microsecond \\ {0, 0}): Builds a new time
to_erl(time): Converts a Time struct to an Erlang time tuple
to_iso8601(time): Converts the given time to ISO8601
to_string(time): Converts the given time to a string

Types

t()

t() :: %Time{hour: Calendar.hour, microsecond: Calendar.microsecond, minute: Calendar.minute, second: Calendar.second}

Functions

from_erl(arg, microsecond \\ {0, 0})

from_erl(:calendar.time, Calendar.microsecond) ::
  {:ok, Time.t} |
  {:error, atom}

Converts an Erlang time tuple to a Time struct.

Examples

iex> Time.from_erl({23, 30, 15}, {5000, 3})
{:ok, ~T[23:30:15.005]}
iex> Time.from_erl({24, 30, 15})
{:error, :invalid_time}

from_erl!(tuple, microsecond \\ {0, 0})

from_erl!(:calendar.time, Calendar.microsecond) ::
  Time.t |
  no_return

Converts an Erlang time tuple to a Time struct.

Examples

iex> Time.from_erl!({23, 30, 15})
~T[23:30:15]
iex> Time.from_erl!({23, 30, 15}, {5000, 3})
~T[23:30:15.005]
iex> Time.from_erl!({24, 30, 15})
** (ArgumentError) cannot convert {24, 30, 15} to time, reason: :invalid_time

from_iso8601(arg)

from_iso8601(String.t) :: {:ok, Time.t} | {:error, atom}

Parses the extended “Local time” format described by ISO8601:2004.

Timezone offset may be included in the string but they will be simply discarded as such information is not included in times.

As specified in the standard, the separator “T” may be omitted if desired as there is no ambiguity within this function.

Time representations with reduced accuracy are not supported.

Examples

iex> Time.from_iso8601("23:50:07")
{:ok, ~T[23:50:07]}
iex> Time.from_iso8601("23:50:07Z")
{:ok, ~T[23:50:07]}
iex> Time.from_iso8601("T23:50:07Z")
{:ok, ~T[23:50:07]}

iex> Time.from_iso8601("23:50:07.0123456")
{:ok, ~T[23:50:07.012345]}
iex> Time.from_iso8601("23:50:07.123Z")
{:ok, ~T[23:50:07.123]}

iex> Time.from_iso8601("2015:01:23 23-50-07")
{:error, :invalid_format}
iex> Time.from_iso8601("23:50:07A")
{:error, :invalid_format}
iex> Time.from_iso8601("23:50:07.")
{:error, :invalid_format}
iex> Time.from_iso8601("23:50:61")
{:error, :invalid_time}

from_iso8601!(string)

from_iso8601!(String.t) :: Time.t | no_return

Parses the extended “Local time” format described by ISO8601:2004.

Raises if the format is invalid.

Examples

iex> Time.from_iso8601!("23:50:07.123Z")
~T[23:50:07.123]
iex> Time.from_iso8601!("2015:01:23 23-50-07")
** (ArgumentError) cannot parse "2015:01:23 23-50-07" as time, reason: :invalid_format

new(hour, minute, second, microsecond \\ {0, 0})

new(Calendar.hour, Calendar.minute, Calendar.second, Calendar.microsecond) ::
  {:ok, Time.t} |
  {:error, atom}

Builds a new time.

Expects all values to be integers. Returns {:ok, time} if each entry fits its appropriate range, returns {:error, reason} otherwise.

Note a time may have 60 seconds in case of leap seconds.

Examples

iex> Time.new(0, 0, 0, 0)
{:ok, ~T[00:00:00.000000]}
iex> Time.new(23, 59, 59, 999_999)
{:ok, ~T[23:59:59.999999]}
iex> Time.new(23, 59, 60, 999_999)
{:ok, ~T[23:59:60.999999]}

# Time with microseconds and their precision
iex> Time.new(23, 59, 60, {10_000, 2})
{:ok, ~T[23:59:60.01]}

iex> Time.new(24, 59, 59, 999_999)
{:error, :invalid_time}
iex> Time.new(23, 60, 59, 999_999)
{:error, :invalid_time}
iex> Time.new(23, 59, 61, 999_999)
{:error, :invalid_time}
iex> Time.new(23, 59, 59, 1_000_000)
{:error, :invalid_time}

to_erl(time)

to_erl(Time.t) :: :calendar.time

Converts a Time struct to an Erlang time tuple.

WARNING: Loss of precision may occur, as Erlang time tuples only contain hours/minutes/seconds.

Examples

iex> Time.to_erl(~T[23:30:15.999])
{23, 30, 15}

to_iso8601(time)

to_iso8601(Time.t) :: String.t

Converts the given time to ISO8601.

Examples

iex> Time.to_iso8601(~T[23:00:13])
"23:00:13"

iex> Time.to_iso8601(~T[23:00:13.001])
"23:00:13.001"

to_string(time)

to_string(Time.t) :: String.t

Converts the given time to a string.

Examples

iex> Time.to_string(~T[23:00:00])
"23:00:00"
iex> Time.to_string(~T[23:00:00.001])
"23:00:00.001"
iex> Time.to_string(~T[23:00:00.123456])
"23:00:00.123456"