/ 
DateTime-Format-Natural-1.18
River stage three • 38 direct dependents • 383 total dependents
/ DateTime::Format::Natural

NAME

DateTime::Format::Natural - Parse informal natural language date/time strings

SYNOPSIS

use DateTime::Format::Natural;

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

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

$date_string  = $parser->extract_datetime($extract_string);
@date_strings = $parser->extract_datetime($extract_string);

if ($parser->success) {
    # operate on $dt/@dt, for example:
    print $dt->strftime('%d.%m.%Y %H:%M:%S'), "\n";
} else {
    warn $parser->error;
}

@traces = $parser->trace;

# examples

12:14 PM
next tuesday at 2am
tomorrow morning
4pm yesterday
10 weeks ago

1st tuesday last november
2nd friday in august
final thursday in april

for 3 hours
monday to friday
1 April 10 am to 1 May 8am

jan 24, 2011 12:00

DESCRIPTION

DateTime::Format::Natural parses informal natural language date/time strings. In addition, parsable date/time substrings may be extracted from ordinary strings.

CONSTRUCTOR

new

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],
          demand_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.

    The format is used to influence how numeric dates are parsed. Given two numbers separated by a slash, the month/day order expected comes from this option. If there is a third number, this option describes where to expect the year. When this format can't be used to interpret the date, some unambiguous dates may be parsed, but there is no form guarantee.

    Current supported "month/day" formats: dd/mm, mm/dd.

    Current supported "year/month/day" formats (with slashes): dd/mm/yy, dd/mm/yyyy, mm/dd/yyyy, yyyy/mm/dd.

    Note that all of the above formats with three units do also parse with dots or dashes as format separators.

    Furthermore, formats can be abbreviated as long as they remain unambiguous.

    Defaults to 'd/m/y'.

  • prefer_future

    Prefers future time and dates. Accepts a boolean, defaults to false.

  • demand_future

    Demands future time and dates. Similar to prefer_future, but stronger. 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

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

METHODS

parse_datetime

Returns a DateTime object constructed from a natural language date/time string.

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

  • string

    The date string.

parse_datetime_duration

Returns one or two DateTime objects constructed from a natural language 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);

extract_datetime

Returns parsable date/time substrings (also known as expressions) extracted from the string provided; in scalar context only the first parsable substring is returned, whereas in list context all parsable substrings are returned. Each extracted substring can then be passed to the parse_datetime()/ parse_datetime_duration() methods.

$date_string  = $parser->extract_datetime($extract_string);
@date_strings = $parser->extract_datetime($extract_string);
# or
$date_string  = $parser->extract_datetime(string => $extract_string);
@date_strings = $parser->extract_datetime(string => $extract_string);

success

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

error

Returns the error message if the parsing did not succeed.

trace

Returns one or two strings with the grammar keyword for the valid expression parsed, traces of methods which were called within the Calc class and a summary how often certain units have been modified. More than one string is commonly returned for durations. Useful as a debugging aid.

GRAMMAR

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 class DateTime::Format::Natural::Lang::EN if you're intending to hack a bit on the grammar guts.

EXAMPLES

See the class DateTime::Format::Natural::Lang::EN for an overview of currently valid input.

BUGS & CAVEATS

parse_datetime()/parse_datetime_duration() always return one or two 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.

CREDITS

Thanks to Tatsuhiko Miyagawa for the initial inspiration. See Miyagawa's journal entry http://use.perl.org/~miyagawa/journal/31378 for more information.

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

Clayton L. Scott
Dave Rolsky
CPAN Author 'SEKIMURA'
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
Wes Morgan
Vladimir Marek
Rod Taylor
Tim Esselens
Colm Dougan
Chifung Fan
Xiao Yafeng
Roman Filippov
David Steinbrunner
Debian Perl Group
Tim Bunce
Ricardo Signes
Felix Ostmann
Jörn Clausen
Jim Avera
Olaf Alders
Karen Etheridge

SEE ALSO

dateparse, DateTime, Date::Calc, http://datetime.perl.org

AUTHOR

Steven Schubiger <schubiger@cpan.org>

LICENSE

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

See http://dev.perl.org/licenses/