Date::Extract(3p)

NAME
Date::Extract - extract probable dates from strings

SYNOPSIS
    my $parser = Date::Extract->new();
    my $dt = $parser->extract($arbitrary_text)
        or die "No date found.";
    return $dt->ymd;

MOTIVATION
There are already a few modules for getting a date out of a string. DateTime::Format::Natural should be your first choice. There's also Time::ParseDate which fits many formats. Finally, you can coerce Date::Manip to do your bidding.

But I needed something that will take an arbitrary block of text, search it for something that looks like a date string, and extract it. This module fills this niche. By design it will produce few false positives. This means it will not catch nearly everything that looks like a date string. So if you have the string "do homework for class 2019" it won't return a DateTime object with the year set to 2019. This is what your users would probably expect.

METHODS

  new PARAMHASH => "Date::Extract"
arguments

format
    Choose what format the extracted date(s) will be. The default is "DateTime", which will return DateTime object(s). Other option include "verbatim" (return the original text), or "epoch" (return Unix timestamp).

time_zone
    Only relevant when "format" is set to "DateTime".

    Forces a particular time zone to be set (this actually matters, as "tomorrow" on Monday at 11 PM means something different than "tomorrow" on Tuesday at 1 AM).

    By default it will use the "floating" time zone. See the documentation for DateTime.

    This controls both the input time zone and output time zone.

prefers
    This argument decides what happens when an ambiguous date appears in the input. For example, "Friday" may refer to any number of Fridays. The valid options for this argument are:

    nearest
        Prefer the nearest date. This is the default.

    future
        Prefer the closest future date.

    past
        Prefer the closest past date. NOT YET SUPPORTED.

returns
    If the text has multiple possible dates, then this argument determines which date will be returned. By default it's 'first'.

    first
        Returns the first date found in the string.

    last
        Returns the final date found in the string.

    earliest
        Returns the date found in the string that chronologically precedes any other date in the string.

    latest
        Returns the date found in the string that chronologically follows any other date in the string.

    all Returns all dates found in the string, in the order they were found in the string.

    all_cron
        Returns all dates found in the string, in chronological order.

  extract text, ARGS => dates
Takes an arbitrary amount of text and extracts one or more dates from it. The return value will be zero or more dates, which by default are DateTime objects (but can be customized with the "format" argument). If called in scalar context, only one will be returned, even if the "returns" argument specifies multiple possible return values.

See the documentation of "new" for the configuration of this method. Any arguments passed into this method will trump those from the constructor.

You may reuse a parser for multiple calls to "extract".

You do not need to have an instantiated "Date::Extract" object to call this method. Just "Date::Extract->extract($foo)" will work.

FORMATS HANDLED

•   today; tomorrow; yesterday

•   last Friday; next Monday; previous Sat

•   Monday; Mon

•   November 13th, 1986; Nov 13, 1986

•   13 November 1986; 13 Nov 1986

•   November 13th; Nov 13

•   13 Nov; 13th November

•   1986/11/13; 1986-11-13

•   11-13-86; 11/13/1986

CAVEATS
This module is intentionally very simple. Surprises are not welcome here.

SEE ALSO
DateTime::Format::Natural, Time::ParseDate, Date::Manip

AUTHOR
Shawn M Moore, "<sartak at bestpractical dot com>"

ACKNOWLEDGEMENTS
Thanks to Steven Schubiger for writing the fine DateTime::Format::Natural. We still use it, but it doesn't quite fill all the particular needs we have.

COPYRIGHT & LICENSE
Copyright 2007-2009 Best Practical Solutions.

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