DateTime::Format::Natural - Create machine readable date/time with natural parsing logic


 use DateTime::Format::Natural;

 $parser = DateTime::Format::Natural->new;

 $dt = $parser->parse_datetime($date_string);
 @dt = $parser->parse_datetime_duration($date_string);

 if ($parser->success) {
     # operate on $dt/@dt, for example:
     printf("%02d.%02d.%4d %02d:%02d:%02d\n", $dt->day,
 } else {
     warn $parser->error;

 @traces = $parser->trace;


DateTime::Format::Natural takes a string with a human readable date/time and creates a machine readable one by applying natural parsing logic.



Creates a new DateTime::Format::Natural object. Arguments to new() are options and not necessarily required.

 $parser = DateTime::Format::Natural->new(
           datetime      => DateTime->new(...),
           lang          => 'en',
           format        => 'mm/dd/yy',
           prefer_future => '[0|1]',
           time_zone     => 'floating',
           daytime       => { morning   => 06,
                              afternoon => 13,
                              evening   => 20,
  • datetime

    Overrides the present now with a DateTime object provided.

  • lang

    Contains the language selected, currently limited to en (english). Defaults to 'en'.

  • format

    Specifies the format of numeric dates, defaults to 'd/m/y'.

  • prefer_future

    Turns ambiguous weekdays/months to their future relatives. Accepts a boolean, defaults to false.

  • time_zone

    The time zone to use when parsing and for output. Accepts any time zone recognized by DateTime. Defaults to 'floating'.

  • daytime

    An anonymous hash reference consisting of customized daytime hours, which may be selectively changed.



Returns a DateTime object constructed from a human readable date/time string.

 $dt = $parser->parse_datetime($date_string);
 $dt = $parser->parse_datetime(string => $date_string);
  • string

    The date string.


Returns one or more DateTime object(s) constructed from a human readable date/time string which may contain timespans/durations. Same interface and options as parse_datetime(), but should be explicitly called in list context.

 @dt = $parser->parse_datetime_duration($date_string);
 @dt = $parser->parse_datetime_duration(string => $date_string);


Returns a boolean indicating success or failure for parsing the date/time string given.


Returns the error message if the parsing did not succeed.


Returns one or more strings with traces of methods which were called within the Base class and a summary how often certain units have been modified. More than one string is commonly returned for durations.


The grammar handling has been rewritten to be easily extendable and hence everybody is encouraged to propose sensible new additions and/or changes.

See the classes DateTime::Format::Natural::Lang::[language_code] if you're intending to hack a bit on the grammar guts.


See the classes DateTime::Format::Natural::Lang::[language_code] for a overview of currently valid input.


parse_datetime()/parse_datetime_duration() always return one or more DateTime objects regardless whether the parse was successful or not. In case no valid expression was found or a failure occurred, an unaltered DateTime object with its initial values (most often the "current" now) is likely to be returned. It is therefore recommended to use success() to assert that the parse did succeed (at least, for common uses), otherwise the absence of a parse failure cannot be guaranteed.

parse_datetime() is not capable of handling durations.


Thanks to Tatsuhiko Miyagawa for the initial inspiration. See Miyagawa's journal entry for more information.

Furthermore, thanks to (in order of appearance) who have contributed valuable suggestions and patches:

 Clayton L. Scott
 Dave Rolsky
 mike (pulsation)
 Mark Stosberg
 Tuomas Jormola
 Cory Watson
 Urs Stotz
 Shawn M. Moore
 Andreas J. König
 Chia-liang Kao
 Jonny Schulz
 Jesse Vincent
 Jason May
 Pat Kale
 Ankur Gupta
 Alex Bowley
 Elliot Shank
 Anirvan Chatterjee
 Michael Reddick
 Christian Brink
 Giovanni Pensa
 Andrew Sterling Hanenkamp
 Eric Wilhelm
 Kevin Field


DateTime, Date::Calc,


Steven Schubiger <>


This program is free software; you may redistribute it and/or modify it under the same terms as Perl itself.


1 POD Error

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Around line 684:

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