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Date-RangeParser-EN-v1.2.1
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/ Date::RangeParser::EN

NAME

Date::RangeParser::EN - Parse plain English date/time range strings

VERSION

version v1.2.1

SYNOPSIS


            

              
              
use Date::RangeParser::EN;
my $parser = Date::RangeParser::EN->new;
my ($begin, $end) = $parser->parse_range("this week");

DESCRIPTION

Parses plain-English strings representing date/time ranges

NAME

Date::RangeParser::EN - Parser for plain English date/time range strings

METHODS

new

Returns a new instance of Date::RangeParser::EN.

Takes an optional hash of parameters:

  • datetime_class

    By default, Date::RangeParser::EN returns two DateTime objects representing the beginning and end of the range. If you use a subclass of DateTime (or another module that implements the DateTime API), you may pass the name of this class to use it instead.

    At the very least, this given class must implement a new method that accepts a hash of arguments, where the following keys will be set:

    
            
    
              
              
    year
    month
    day
    hour
    minute
    second

    This gives you the freedom to set your time zones and such however you need to.

  • infinite_past_class =item * infinite_future_class

    By default, Date::RangeParser::EN uses DateTime::Infinite::Past and DateTime::Infinite::Future to create open-ended ranges (for example "after today"). If you have extended these classes, you may pass the corresponding names in.

    The given classes must implement a new method that accepts no arguments.

  • now_callback

    By default, Date::RangeParser::EN uses DateTime->now to determine the current date/time for calculations. If you need to work with a different time (for instance, if you need to adjust for time zones), you may pass a callback (code reference) which returns a DateTime object.

parse_range

Accepts a string representing a plain-English date range, for instance:

  • today

  • this week

  • the past 2 months

  • next Tuesday

  • two weeks ago

  • the next 3 hours

  • the 3rd of next month

  • the end of this month

More formally, this will parse the following kinds of date strings:


            

              
              
NUMBER : ordinary number (1)
PERIOD : one of: hour, day, week, month, quarter, or year (or the plural of these)
WEEKDAY : one of: Monday, Tuesday, Wedensday, Thursday, Friday, Saturday, or Sunday
CARDINAL : a cardinal number (21st) or the word for that number (twenty-first) or end
MONTH : a month name: January, Feburary, March, April, May, June, July August, 
        September, October, November, or Decmeber or any 3-letter abbreviation
YEAR : a 4-digit year (2-digits will not work)
TIMES: January 1st, 2000 at 10:00am through January 1st, 2000 at 2:00pm
RANGE : any date range that can be parsed by parse_range
ELEMENT : any element of a date range that can be parsed by parse_range
today                             : today, midnight to midnight
this PERIOD                       : the current period, start to end
this month
current PERIOD                    : the current period, start to end
current year
this WEEKDAY                      : the WEEKDAY that is in the current week, midnight to midnight
this Monday
NUMBER PERIOD ago                 : past date relative to now until now
3 days ago
past NUMBER PERIOD                : past date relative to now until now
past 2 weeks
last NUMBER PERIOD                : past date relative to now until now
last 6 hours
past NUMBER WEEKDAY               : the weekday a number of weeks before now until now
past 4 Saturdays
NUMBER WEEKDAY ago                : the weekday a number of weeks before now until now
3 Fridays ago
yesterday                         : yesterday, midnight to midnight
last WEEKDAY                      : the WEEKDAY that is in the week prior to this, midnight to midnight
last Wednesday
previous WEEKDAY                  : the WEEKDAY that is in the week prior to this, midnight to midnight
previous Friday
past WEEKDAY                      : the WEEKDAY that is in the week prior to this, midnight to midnight
past Tuesday
this past WEEKDAY                 : the WEEKDAY that is in the week prior to this, midnight to midnight
this past Saturday
coming WEEKDAY                    : the WEEKDAY that is in the week after this, midnight to midnight
coming Monday
this coming WEEKDAY               : the WEEKDAY that is in the week after this, midnight to midnight
this coming Thursday
NUMBER Business days ago          : past number of business days relative to now until now
NUMBER weekdays ago               : past number of weekdays relative to now until now
LAST or PAST NUMBER weekdays ago  : past number of weekdays relative to now until now
NUMBER PERIOD hence               : now to a future date relative to now
4 months hence
NUMBER PERIOD from now            : now to a future date relative to now
6 days from now
next NUMBER PERIOD                : now to a future date relative to now
next 7 years
tomorrow                          : tomorrow, midnight to midnight
next NUMBER WEEKDAY               : the WEEKDAY that is in a number of weeks after this, midnight to midnight
next 4 Sundays
CARDINAL of this month            : the specified day of the current month, midnight to midnight
14th of this month
CARDINAL of last month            : the specified day of the previous month, midnight to midnight
31st of last month
CARDINAL of next month            : the specified day of the month following this, midnight to midnight
3rd of next month
CARDINAL of NUMBER months ago     : the specified day of a previous month, midnight to midnight
12th of 2 months ago
CARDINAL of NUMBER months from now : the specified day of a following month, midnight to midnight
7th of 22 months from now
CARDINAL of NUMBER months hence   : the specified day of a following month, midnight to midnight
22nd of 6 months hence
CARDINAL of TIME                  : the specific time of day which can be accompanied by a date
10:00am through 12:00pm             defaults to today if no date is given
MONTH                             : the named month of the current year, 1st to last day
August
this MONTH                        : the named month of the current year, 1st to last day
this Sep
last MONTH                        : the named month of the previous year, 1st to last day
last January
next MONTH                        : the named month of the next year, 1st to last day
next Dec
MONTH YEAR                        : the named month of the named year, 1st to last day
June 1969
RANGE to RANGE                    : the very start of the first range to the very end of the second
Tuesday to Next Saturday
RANGE thru RANGE                  : the very start of the first range to the very end of the second
2 hours ago thru the next 6 hours
RANGE through RANGE               : the very start of the first range to the very end of the second
August through December
RANGE - RANGE                     : the very start of the first range to the very end of the second
9-1-2012 - 9-30-2012
RANGE-RANGE                       : the very start of the first range to the very end of the second
10/10-10/20                         (ranges must not contain hyphens, "-")
American style dates              : Month / Day / Year
6/15/2000
before ELEMENT                    : all dates before the very start of the date specified in the ELEMENT
     < ELEMENT
before today
<= ELEMENT                        : all dates up to the very end of the date specified in the ELEMENT
<= today
after ELEMENT                     : all dates after the very end of the date specified in the ELEMENT
    > ELEMENT
after next Tuesday
>= ELEMENT                        : the date specified in the ELEMENT to the end of forever
>= this Friday
since ELEMENT                     : the date specified in the ELEMENT to the end of the current day
since last Sunday

Anything else is parsed by Date::Manip. If Date::Manip is unable to parse the date given either, then the dates returned will be undefined.

Also, when parsing:

  • The words "the" and "and" will always be ignored and can appear anywhere.

  • Cardinal numbers may be spelled out as words, i.e. "September first" instead of "September 1st". Similarly, "two weeks ago" and "2 weeks ago" will be treated as the same

  • Any plural or singular period shown above can be used with the opposite.

  • All dates are parsed relative to the parser's notion of now. You can control this by setting the now_callback option on the constructor.

Returns two DateTime objects, representing the beginning and end of the range.

_convert_from_us_dashed

Converts a US date string in the format MM-DD-YYYY into a datetime object.

_clean_units

Given a unit of measurement such as hours?, minutes?, seconds?, or days?, we will return a string of the form hours, minutes, seconds, or days.

TO DO

There's a lot more that this module could handle. A few items that come to mind:

  • More testing to make sure certain date configurations are handled, like start of week.

  • Handle Unicode in places where such handling makes sense (like hyphen detection)

  • Allow full words instead of digits ("two weeks ago" vs "2 weeks ago")

  • Allow "between" for ranges ("between last February and this Friday") in addition to "to/through" ranges

  • This module is US English-centric (hence the "EN") and might do some things wrong for other variants of English and a generic Date::RangeParser interface could be made to allow for other languages to be parsed this way.

  • Depends on Date::Manip. This may or may not be a good thing.

DEPENDENCIES

DateTime, Date::Manip

AUTHORS

This module was authored by Grant Street Group (http://grantstreet.com), who were kind enough to give it back to the Perl community.

The CPAN distribution is maintained by Grant Street Group <developers@grantstreet.com>.

THANK YOU

Sterling Hanenkamp, for adding support for explicit date ranges, improved parsing, and improving the documentation.

Sam Varshavchik, for fixing a bug affecting the "[ordinal] of [last/next] month" syntax.

Allan Noah and James Hammer, for adding support for times in addition to dates and various bug fixes.

COPYRIGHT AND LICENSE

Copyright (C) 2012-2023 Grant Street Group.

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

AUTHORS

  • Grant Street Group <developers@grantstreet.com>

  • Michael Aquilina <aquilina@cpan.org>

COPYRIGHT AND LICENSE

This software is Copyright (c) 2012 - 2024 by Grant Street Group.

This is free software, licensed under:


            

              
              
The Artistic License 2.0 (GPL Compatible)