NAME
DateTime::Format::Human::Duration - Get a locale specific string
describing the span of a given duration
SYNOPSIS
use DateTime;
use DateTime::Format::Human::Duration
my $span = DateTime::Format::Human::Duration->new();
my $dur = $dta - $dtb;
print $span->format_duration($dur); # 1 year, 2 months, 3 minutes, and 1 second
print $span->format_duration_between($dta, $dtb); # 1 year, 2 months, 3 minutes, and 1 second
DESCRIPTION
Get a localized string representing the duration.
For example:
1 second
2 minutes and 3 seconds
3 weeks, 1 day, and 5 seconds
4 years, 1 month, 2 days, 6 minutes, 1 second, and 345000028 nanoseconds
INTERFACE
new()
Create span object, no args
format_duration()
First argument is a DateTime::Duration object
After that you can optionally pass some standard args as a hash as
described below
format_duration_between()
First two args are DateTime objects
After that you can optionally pass some standard args as a hash as
described below
standard args
1. 'locale'
locale of the $dt object will be used if you do not specify this
Valid values are a string of the locale (E.g 'fr'), a DateTime
object, or a DateTime object's 'locale' key.
2. Since we're working with 2 DateTime objects of known points we can
have past and future tenses.
* past
String to use if duration is past tense. Can have a sprintf '%s'
or else is prepended with a trailing space.
* future
String to use if duration is future tense. Can have a sprintf
'%s' or else is prepended with a trailing space.
* no_time
Override the 'no_time' in the locale hash.
If duration is baseless (IE ambiguous) then 'past' and 'future' is
used based on if $dur->in_units has negatives or not.
Also by nature it's not split into type groups:
An example is
DateTime::Duration->new('seconds'=> 62)
Will result in '62 seconds' not '1 minute and 2 seconds'
For more sane results always be specific by using 2 datetime object
to get a duration object
print $dt->format_duration_between(
$dta,
$dtb,
'past' => 'Your account expired %s ago.',
'future' => 'Your account expires in %s.',
'no_time'=> 'Your account just expired.',
);
This facilitates, for example, this Locale::Maketext vernacular
which becomes:
'Your account [duration,_1,_2,expired %s ago,expires in,just expired].' => '[Votre compte [duration,_1,_2,a expiré il ya,expire dans,vient d'expirer].'
3. Time Resolution and Units
* units
Specify units to format duration with. Arguments will be passed
to DateTime::Format's in_unit() method.
Example:
my $fmt = DateTime::Format::Human::Duration->new();
my $d = DateTime::Duration->new(...);
my $s = $fmt->format_duration($d, 'units' => [qw/years months days/] );
# $s == '1 year, 7 months, and 16 days'
Possible values include: years months weeks days hours minutes
seconds nanoseconds
* precision
By default, the duration will be formatted using nanosecond
resolution. Resolution can be reduced by passing 'years',
'months', 'weeks', 'days', 'hours', 'minutes', or 'seconds' to
the 'precision' argument.
Example:
my $fmt = DateTime::Format::Human::Duration->new();
my $d = DateTime::Duration->new(...);
print $fmt->format_duration($d);
# '1 year, 7 months, 2 weeks, 2 days, 13 hours, 43 minutes, and 15 seconds'
print $fmt->format_duration($d, 'precision' => 'days');
# '1 year, 7 months, 2 weeks, and 2 days'
* significant_units
By default, the duration will be formatted using all specified
units. To restrict the number of units output, set this to a
value of one or more.
Example:
my $fmt = DateTime::Format::Human::Duration->new();
my $d = DateTime::Duration->new(...);
print $fmt->format_duration($d, 'significant_units' => 1);
# '3 days'
print $fmt->format_duration($d, 'significant_units' => 2);
# '3 days and 10 hours'
print $fmt->format_duration($d, 'significant_units' => 3);
# '3 days, 10 hours, and 27 minutes'
LOCALIZATION
Localization is provided by the included
DateTime::Format::Human::Duration::Locale modules.
Included are DateTime::Format::Human::Duration::Locale::es,
DateTime::Format::Human::Duration::Locale::fr,
DateTime::Format::Human::Duration::Locale::pt,
DateTime::Format::Human::Duration::Locale::de,
DateTime::Format::Human::Duration::Locale::it
More will be included as time permits/folks volunteer/CLDR becomes an
option
They are setup this way:
DateTime::Format::Human::Duration::Locale::XYZ where 'XYZ' is the ISO
code of DateTime::Locale
It can have one of 2 functions:
get_human_span_hashref()
Takes no arguments, should return a hashref of this structure:
sub get_human_span_hashref {
return {
'no_oxford_comma' => 1,
'no_time' => 'pas le temps',
'and' => 'et',
'year' => 'an',
'years' => 'ans',
'month' => 'mois',
'months' => 'mois',
'week' => 'semaine',
'weeks' => 'semaines',
'day' => 'jour',
'days' => 'jours',
'hour' => 'heure',
'hours' => 'heures',
'minute' => 'minute',
'minutes' => 'minutes',
'second' => 'seconde',
'seconds' => 'seconds',
'nanosecond' => 'nanoseconde',
'nanoseconds' => 'nanosecondes',
};
}
get_human_span_from_units()
Try to use get_human_span_hashref() if the locale allows for it
since it's much easier. If you cannot, however, then this will give
you the maximum level of configurability.
This function receives a hashref of duration values, and a hashref
of the standard args. It should return the localized string.
sub get_human_span_from_units {
my ($duration_values_hr, $args_hr) = @_;
...;
return $string; # 1 year, 2days, 4 hours, and 17 minutes
}
Please see the example in
`t/lib/DateTime/Format/Human/Duration/Locale/nb.pm'.
LOCALIZATION of DateTime::Format modules
DateTime does an excellent job at implementing localization. Often
DateTime::Format based class's either don't support localization or they
implement it haphazardly and inconsistently.
With this module I hope to model a localization scheme that is inline
with DateTime and is consistent and reuseable between <DateTime::Format>
based classes.
The idea is to determine the locale to use based on a DateTime object.
XYZ::Locale should handle looking up (and caching if appropriate) the
locale and loading the necessary locale module XYZ::Locale::fr
The specific locale module holds the data and possibly logic necessary
to do what XYZ does in the vernacular of the given locale.
TODO
Eventually the generic logic will be re-broken out into its own module
for re-use by your class and I'll have more detailed POD about how to do
it.
In the meantime if you're interested please contact me and I'd be happy
to help and/or expediate this TODO.
Also, Dave Rolksy has mentioned to me that this sort of locale data
might be appropriate for DateTime::Locale directly from CLDR. If that
happens this module will be changed to use that if possible.
FAQ
Why would I want to use this?
So you can localize your application's output of time periods without
having to do a lot of logic each time you wanted to say it.
Locale::Maketext::Utils has/will have a duration() bracket notation
method which prompted this module's existence
duration() was prompted by its datetime() brother, all of which uses the
most excellent DateTime project!
Why did my duration say '62 seconds' instead of '1 minute and 2 seconds'
Because you used an ambiguous duration (one without a base) so there is
no way to apply date math and accurately represent the number of each
given item in that duration since it may or may not span leap-[second,
days, years, etc..]
In other words do this (so that your duration can be specifically
calculated):
$dtb = $dta->clone->add('seconds'=> 62);
my $duration = $dta - $dtb; # has a base, its not ambiguous
print $span->format_duration($duration); # 1 minutes and 2 seconds
not this:
my $duration = DateTime::Duration->new('seconds'=> 62); # no base, it is ambiguous
print $span->format_duration($duration); # 62 seconds
Note format_duration_between(), does not suffer from this since we're
using a specific DateTime object already.
print $span->format_duration_between( $dt, $dt->clone()->add('seconds'=> 62) ); # 1 minute and 2 seconds
Why do you put a comma before the 'and' in a group of more than 2 items?
We want to use the so-called Oxford comma to avoid ambiguity.
My DateTime::Format::Human::Duration::Locale::XX still outputs in English!
That is because it defined neither the get_human_span_hashref() or the
get_human_span_from_units() functions
It must define one of them or defaults are used.
Why didn't you just use 'DateTime::Format::Duration'
Essencially DateTime::Format::Duration is an object representing a
single strftime() type string to apply to any given duration. This is
not flexible enough for the intent of this module.
DateTime::Format::Duration is not a bad module its just for a different
purpose than DateTime::Format::Human::Duration
* It was not localizable
You either got '2 days' or '1 days' which a) forces it to be in
English and b) doesn't even make sense in English.
You could get around that by adding logic each time you wanted to
call it but that is just messy.
* Had to keep an item even if it was zero
If 'days' was in there you got '0 days', we only want items with a
value to show.
That'd also require a lot of logic each time you wanted to call
which is again messy.
* This module has no need for reparsing output back into an object
Since the datetime info for 2 points in time are generally in a form
easily rendered into a DateTime object it'd be silly to even attempt
to store and parse the output of this module back into an object.
Plus since it all depends on the locale it is in it'd be difficult.
The purpose of DateTime::Format::Human::Duration was to generate a
localized human language description of a duration without the caller
needing to supply any logic.
DIAGNOSTICS
Throws no warnings or errors of its own
CONFIGURATION AND ENVIRONMENT
DateTime::Format::Human::Duration requires no configuration files or
environment variables.
DEPENDENCIES
None.
INCOMPATIBILITIES
None reported.
BUGS AND LIMITATIONS
No bugs have been reported.
Please report any bugs or feature requests to
`bug-datetime-format-span@rt.cpan.org', or through the web interface at
http://rt.cpan.org.
AUTHOR
Daniel Muey `<http://drmuey.com/cpan_contact.pl>'
LICENCE AND COPYRIGHT
Copyright (c) 2008, Daniel Muey `<http://drmuey.com/cpan_contact.pl>'.
All rights reserved.
This module is free software; you can redistribute it and/or modify it
under the same terms as Perl itself. See perlartistic.
DISCLAIMER OF WARRANTY
BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
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OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER
EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE
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