Kernel.sigil_U

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sigil_U(datetime_string, modifiers)

View Source (macro) (since 1.9.0)

Handles the sigil ~U to create a UTC DateTime.

By default, this sigil uses the built-in Calendar.ISO, which requires UTC date times to be written in the ISO8601 format:

~U[yyyy-mm-dd hh:mm:ssZ]
~U[yyyy-mm-dd hh:mm:ss.ssssssZ]
~U[yyyy-mm-ddThh:mm:ss.ssssss+00:00]

such as:

~U[2015-01-13 13:00:07Z]
~U[2015-01-13T13:00:07.123+00:00]

If you are using alternative calendars, any representation can be used as long as you follow the representation by a single space and the calendar name:

~U[SOME-REPRESENTATION My.Alternative.Calendar]

The given datetime_string must include "Z" or "00:00" offset which marks it as UTC, otherwise an error is raised.

The lower case ~u variant does not exist as interpolation and escape characters are not useful for date time sigils.

More information on date times can be found in the DateTime module.

Examples

iex> ~U[2015-01-13 13:00:07Z]
~U[2015-01-13 13:00:07Z]
iex> ~U[2015-01-13T13:00:07.001+00:00]
~U[2015-01-13 13:00:07.001Z]