Re^2: oo design q: SUPER::

Thanks to both of you for your help. Incidentally, lestrrat, there is a minor error in your (elegant) solution: my %args = @_; assigns to the hash keys, so the foreach loop $self->{key} = $args{$key} actually assigns a null value to $self->{key}.

I mention this just in case someone else grabs this code in the future and spends a few minutes scratching their head, like I did. Luckily, the fix is even simpler:

package Dragon

sub _init {
    my $self = shift;
    foreach my $key qw(NAME AGE COLOR) {
        $self->{$key} = shift;
    }
}
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In the unlikely event that anyone is interested, my complete code follows:

Dragon.pm

package Dragon;
use strict;

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 from your slumber!
    return $self;
}

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

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 "an " : 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 _init {
    my $self = shift;
    $self->{NAME} = "Trogdor";
    $self->{AGE}  = "one year old";
    $self->{COLOR}= "green";
}

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

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

my $d = new Dragon(); # create a nameless dragon
my $smaug = new Dragon("Smaug","centuries old");   # create Smaug
my $trogdor = new Trogdor(); # create Trodgor
$trogdor->burninate(); # burninate!
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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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