horrible data structure ... :(

use warnings;
use strict;
use Data::Dump;


my @unsorted =qw(
Dec02
Jan02
May05
Dec01
Apr05
May15
);


my @sorted= sort datesort @unsorted;
dd \@unsorted,\@sorted;


  
my @months= qw(
         Jan
         Feb
         Mar
         Apr
         May
         Jun
         Jul
         Aug
         Sep
         Oct
         Nov
         Dec
        );

my %month_order;
@month_order{@months} = 1..12;

#dd \%month_order;


  
sub datesort {
    my ($am,$ay) = $a =~ /(\w\w\w)(\d\d)/;
    my ($bm,$by) = $b =~ /(\w\w\w)(\d\d)/;

    return
      $ay <=> $by or
      $month_order{$am} <=> $month_order{$bm};
}
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