Takes a NaiveDateTime and an integer. Returns the naive_date_time advanced by the number of seconds found in the seconds argument.

If seconds is negative, the time is moved back.

Examples

# Advance 2 seconds
iex> from_erl!({{2014,10,2},{0,29,10}}, 123456) |> advance(2)
{:ok, %Calendar.NaiveDateTime{day: 2, hour: 0, min: 29, month: 10,
      sec: 12, usec: 123456,
      year: 2014}}

Like advance without exclamation points. Instead of returning a tuple with :ok and the result, the result is returned untagged. Will raise an error in case no correct result can be found based on the arguments.

Examples

# Advance 2 seconds
iex> from_erl!({{2014,10,2},{0,29,10}}, 123456) |> advance!(2)
%Calendar.NaiveDateTime{day: 2, hour: 0, min: 29, month: 10,
      sec: 12, usec: 123456,
      year: 2014}

Takes an Erlang-style date-time tuple. If the datetime is valid it returns a tuple with a tag and a naive DateTime. Naive in this context means that it does not have any timezone data.

Examples

iex>from_erl({{2014, 9, 26}, {17, 10, 20}})
{:ok, %Calendar.NaiveDateTime{day: 26, hour: 17, min: 10, month: 9, sec: 20, year: 2014} }

iex>from_erl({{2014, 9, 26}, {17, 10, 20}}, 321321)
{:ok, %Calendar.NaiveDateTime{day: 26, hour: 17, min: 10, month: 9, sec: 20, year: 2014, usec: 321321} }

# Invalid date
iex>from_erl({{2014, 99, 99}, {17, 10, 20}})
{:error, :invalid_datetime}

# Invalid time
iex>from_erl({{2014, 9, 26}, {17, 70, 20}})
{:error, :invalid_datetime}

Like from_erl/1 without "!", but returns the result directly without a tag. Will raise if date is invalid. Only use this if you are sure the date is valid.

Examples

iex> from_erl!({{2014, 9, 26}, {17, 10, 20}})
%Calendar.NaiveDateTime{day: 26, hour: 17, min: 10, month: 9, sec: 20, year: 2014}

iex from_erl!({{2014, 99, 99}, {17, 10, 20}})
# this will throw a MatchError

Takes a NaiveDateTime and returns an integer of gregorian seconds starting with year 0. This is done via the Erlang calendar module.

Examples

iex> from_erl!({{2014,9,26},{17,10,20}}) |> gregorian_seconds
63578970620

DEPRICATED. Use Calendar.Strftime.strftime!/3 instead - it works the same way.

Takes a NaiveDateTime struct and returns a Date struct representing the date part of the provided NaiveDateTime.

iex> from_erl!({{2014,10,15},{2,37,22}}) |> Calendar.NaiveDateTime.to_date
%Calendar.Date{day: 15, month: 10, year: 2014}

For turning NaiveDateTime structs to into a DateTime.

Takes a NaiveDateTime and a timezone name. If timezone is valid, returns a tuple with an :ok and DateTime.

iex> from_erl!({{2014,10,15},{2,37,22}}) |> Calendar.NaiveDateTime.to_date_time("UTC")
{:ok, %Calendar.DateTime{abbr: "UTC", day: 15, usec: nil, hour: 2, min: 37, month: 10, sec: 22, std_off: 0, timezone: "UTC", utc_off: 0, year: 2014}}

Promote to DateTime with UTC time zone. Should only be used if you are sure that the provided argument is in UTC.

Takes a NaiveDateTime. Returns a DateTime.

iex> from_erl!({{2014,10,15},{2,37,22}}) |> Calendar.NaiveDateTime.to_date_time_utc
%Calendar.DateTime{abbr: "UTC", day: 15, usec: nil, hour: 2, min: 37, month: 10, sec: 22, std_off: 0, timezone: "Etc/UTC", utc_off: 0, year: 2014}

Takes a NaiveDateTime struct and returns an erlang style datetime tuple.

Examples

iex> from_erl!({{2014, 10, 15}, {2, 37, 22}}) |> to_erl
{{2014, 10, 15}, {2, 37, 22}}

Takes a NaiveDateTime struct and returns an Ecto style datetime tuple. This is like an erlang style tuple, but with microseconds added as an additional element in the time part of the tuple.

If the datetime has its usec field set to nil, 0 will be used for usec.

Examples

iex> from_erl!({{2014,10,15},{2,37,22}}, 999999) |> Calendar.NaiveDateTime.to_micro_erl
{{2014, 10, 15}, {2, 37, 22, 999999}}

iex> from_erl!({{2014,10,15},{2,37,22}}, nil) |> Calendar.NaiveDateTime.to_micro_erl
{{2014, 10, 15}, {2, 37, 22, 0}}

Takes a NaiveDateTime struct and returns a Time struct representing the time part of the provided NaiveDateTime.

iex> from_erl!({{2014,10,15},{2,37,22}}) |> Calendar.NaiveDateTime.to_time
%Calendar.Time{usec: nil, hour: 2, min: 37, sec: 22}

If you have a naive datetime and you know the offset, promote it to a UTC DateTime.

Examples

# A naive datetime at 2:37:22 with a 3600 second offset will return
# a UTC DateTime with the same date, but at 1:37:22
iex> with_offset_to_datetime_utc {{2014,10,15},{2,37,22}}, 3600
{:ok, %Calendar.DateTime{abbr: "UTC", day: 15, usec: nil, hour: 1, min: 37, month: 10, sec: 22, std_off: 0, timezone: "Etc/UTC", utc_off: 0, year: 2014} }
iex> with_offset_to_datetime_utc{{2014,10,15},{2,37,22}}, 999_999_999_999_999_999_999_999_999
{:error, nil}