P
PerlFAQ Server
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 .
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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.
The "Time:
iece" module, which comes with Perl, replaces "localtime"
with a version that returns an object. It also overloads the comparison
operators so you can compare them directly:
use Time:iece;
my $date1 = localtime( $some_time );
my $date2 = localtime( $some_other_time );
if( $date1 < $date2 ) {
print "The date was in the past\n";
}
You can also get differences with a subtraction, which returns a
"Time::Seconds" object:
my $diff = $date1 - $date2;
print "The difference is ", $date_diff->days, " days\n";
If you want to work with formatted dates, the "Date::Manip",
"Date::Calc", or "DateTime" modules can help you.
--------------------------------------------------------------------
The perlfaq-workers, a group of volunteers, maintain the perlfaq. They
are not necessarily experts in every domain where Perl might show up,
so please include as much information as possible and relevant in any
corrections. The perlfaq-workers also don't have access to every
operating system or platform, so please include relevant details for
corrections to examples that do not work on particular platforms.
Working code is greatly appreciated.
If you'd like to help maintain the perlfaq, see the details in
perlfaq.pod.
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.
The "Time:
iece" module, which comes with Perl, replaces "localtime"with a version that returns an object. It also overloads the comparison
operators so you can compare them directly:
use Time:
iece;my $date1 = localtime( $some_time );
my $date2 = localtime( $some_other_time );
if( $date1 < $date2 ) {
print "The date was in the past\n";
}
You can also get differences with a subtraction, which returns a
"Time::Seconds" object:
my $diff = $date1 - $date2;
print "The difference is ", $date_diff->days, " days\n";
If you want to work with formatted dates, the "Date::Manip",
"Date::Calc", or "DateTime" modules can help you.
--------------------------------------------------------------------
The perlfaq-workers, a group of volunteers, maintain the perlfaq. They
are not necessarily experts in every domain where Perl might show up,
so please include as much information as possible and relevant in any
corrections. The perlfaq-workers also don't have access to every
operating system or platform, so please include relevant details for
corrections to examples that do not work on particular platforms.
Working code is greatly appreciated.
If you'd like to help maintain the perlfaq, see the details in
perlfaq.pod.