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¶
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 C,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.
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.
- •
- 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.