Re: FAQ 4.14 How can I compare two dates and find the difference?

[email protected] (James Wright) Mon, 07 Feb 2011 10:12:20 -0800
Newsgroups perl.perlfaq.workers
Message-ID <[email protected]>
On 02/06/11 03:00, PerlFAQ Server wrote:
> This is an excerpt from the latest version perlfaq4.pod, which
> comes with the standard Perl distribution. These postings aim to
> reduce the number of repeated questions as well as allow the community
> to review and update the answers. The latest version of the complete
> perlfaq is at http://faq.perl.org .
>
> --------------------------------------------------------------------
>
> 4.14: How can I compare two dates and find the difference?
>
>      (contributed by brian d foy)
>
>      You could just store all your dates as a number and then subtract. Life
>      isn't always that simple though. If you want to work with formatted
>      dates, the "Date::Manip", "Date::Calc", or "DateTime" modules can help
>      you.
>
>
>
> --------------------------------------------------------------------
>
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Perhaps mention the core Time::Piece + Time::Seconds modules before the 
non-core modules here?  Could also add an example, like this:

use Time::Piece;
use Time::Seconds;

my $date_one = Time::Piece->strptime('Feb 1 2011', '%b %d %Y');
my $date_two = Time::Piece->strptime('Dec 31 2010', '%b %d %Y');

my $date_diff = $date_one - $date_two;
print "Difference is: ", $date_diff->days, " days\n";

In fact, couldn't 'mention Time::Piece and/or Time::Seconds' be applied 
to most of the answers in perlfaq4?  As an example, 'How can I take a 
string and turn it into epoch seconds?' can be answered by referring to 
the strptime function in Time::Piece.  And Time::Piece has the methods 
to answer all the questions in 'How can I find the Julian Day?'