How can I get approximate time passed since some timestamp? - perl

Question

Is there any useful module on CPAN that returns number of biggest fractions of date interval, i.e. return integer number of years/months/days/hours/minutes/seconds between two dates, to use in sentence like "N days ago" or "M months ago"

Answer 1

DateTime and DateTime::Duration are the best modules:
use strict;
use warnings;
use DateTime;
use DateTime::Duration;
use Data::Dumper;
my $dt1 = DateTime->now;
my $dt2 = DateTime->new(
year => 2001,
month => 01,
day => 01
);
my $duration = $dt1 - $dt2;
print Dumper($duration);
produces:
$VAR1 = bless( {
'seconds' => 38,
'minutes' => 181,
'end_of_month' => 'wrap',
'nanoseconds' => 0,
'days' => 20,
'months' => 110
}, 'DateTime::Duration' );
You can format absolute times and durations using the sister modules DateTime::Format and DateTime::Format::Duration.

Answer 2

Well, not very difficult to write your own.
Calculate relative time in C#

Answer 3

Time::Duration seems to be a natural choice for what you try to accomplish. I haven't tried it though. Only caveat seems to be that it already gives you phrases like "M months ago", so you might need to parse its output for non-English output.

Answer 4

You might take a look at the Time::Ago module on CPAN (I'm the author). It's a Perl port of the time_ago_in_words() helper from Rails.
Given a duration, it returns a readable string approximation. From the Rails docs:
0 29 secs
less than a minute
30 secs 1 min, 29 secs
1 minute
1 min, 30 secs 44 mins, 29 secs
[2..44] minutes
44 mins, 30 secs 89 mins, 29 secs
about 1 hour
89 mins, 30 secs 23 hrs, 59 mins, 29 secs
about [2..24] hours
23 hrs, 59 mins, 30 secs 41 hrs, 59 mins, 29 secs
1 day
41 hrs, 59 mins, 30 secs 29 days, 23 hrs, 59 mins, 29 secs
[2..29] days
29 days, 23 hrs, 59 mins, 30 secs 44 days, 23 hrs, 59 mins, 29 secs
about 1 month
44 days, 23 hrs, 59 mins, 30 secs 59 days, 23 hrs, 59 mins, 29 secs
about 2 months
59 days, 23 hrs, 59 mins, 30 secs 1 yr minus 1 sec
[2..12] months
1 yr 1 yr, 3 months
about 1 year
1 yr, 3 months 1 yr, 9 months
over 1 year
1 yr, 9 months 2 yr minus 1 sec
almost 2 years
2 yrs max time or date
(same rules as 1 yr)
CPAN module
Repository

Answer 5

[This isn't really an answer, but I think it's relevant.]
If you're going to get into date/time manipulation and calculation, you're best off keeping to the DateTime family of modules. Not only do they have the best handling of timezones that I've found, but they all work with each other. I've never had a problem in this domain which I couldn't find a module in DateTime to solve it.