How can I change the date formats in Perl?

Question

I just want to convert the dates from 20111230 format to 30-dec-2011.

Answer 1

In keeping with TMTOWTDI, you can use Time::Piece

#!/usr/bin/env perl
use strict;
use warnings;
use Time::Piece;
my $t = Time::Piece->strptime("20111230", "%Y%m%d");
print $t->strftime("%d-%b-%Y\n");

Answer 2

If I can't use one of the date modules, POSIX isn't so bad and it comes with perl:

use v5.10;
use POSIX qw(strftime);

my $date = '19700101';

my @times;
@times[5,4,3] = $date =~ m/\A(\d{4})(\d{2})(\d{2})\z/;
$times[5] -= 1900;
$times[4] -= 1;

# strftime(fmt, sec, min, hour, mday, mon, year, wday = -1, yday = -1, isdst = -1)
say strftime( '%d-%b-%Y', @times );

Making @times is a bit ugly. You can't always get what you want, but if you try sometimes, you might find you get what you need.