Dragon.pm

package Dragon;
use strict;
use Data::Dumper;

sub new() {
    my $class = shift;          # get class so constructor can be inhe
+rited
    my $self = {};
    bless ($self,$class);
    $self->_init( @_ );         # call _init here or in subclass
    $self->awaken;              # arise!
    return $self;
}

sub _init {
    my $self = shift;
    my %args = @_;
    foreach my $key qw(NAME AGE COLOR) {
        $self->{$key} = $args{$key};
    }
}

sub get_name {
    my $self = shift;
    return $self->{NAME} || "nameless";
}

sub get_age {
    my $self = shift;
    return $self->{AGE} || "ageless";
}

sub get_color {
    my $self = shift;
    return $self->{COLOR} || "obscure";
}

sub awaken {
    my $self = shift;
    ($self->get_name eq "nameless") ? print "A " : 0;
    print $self->get_name .", ";
    ($self->get_name ne "nameless") ? print "the " : 0;
    print $self->get_age .", ";
    print $self->get_color ." dragon awakens from his slumber!\n";
}
1;
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Trogdor.pm

package Trogdor;
use strict;
use base qw(Dragon);

sub new {
    my $class = shift;
    $class->SUPER::new(
        NAME  => "Trogdor",
        AGE   => "one year old",
        COLOR => "green",
        @_,                             # allows us to override defaul
+ts
        );
}

sub burninate {
    my $self = shift;
    print $self->get_name ." burninates the land!\n";
}
1;
[download]

dragons.pl (test script)

#!/usr/bin/perl
use strict;
use Trogdor;

my $d = new Trogdor(); # create Trodgor
my $e = new Dragon(NAME => 'Smaug'); # create Smaug
my $f = new Dragon(); # create anonymous dragon
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Using perl 5.8.1-RC3 unless otherwise noted.
Apache/1.3.33 (Darwin) unless otherwise noted.
Mac OS X 10.3.9 unless otherwise noted.
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