No, adrianh is absolutely correct. In fact, this is very good style because it allows inheritance of behavior while allowing alterations to that behavior transparently based upon the concrete subclass you are actually instantiating.

Here's an example of bad, inflexible, child-snooping that you want to be concerned about:

package FamilyMember; # the parent class of Son, Daughter
sub new {
    my ($class, $args) = @_;
    my $self = bless({}, $class);
    if ($class eq 'Son') {
        $self->askSantaFor('A Truck!');
    } elsif ($class eq Daughter') {
        $self->askSantaFor("Subscription to Martha Stewart's 'Living'"
+);
    }
return $self;
}

sub askSantaFor {
    my ($self, $wish);
    push @{$self->{things_to_ask_for}}, $wish;
}
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What happens if you need to add a new subclass called StepDaughter? You have to go to the superclass and modify the constructor. The better way is just what you've done, and in this silly example the solution would be either to override askSantaFor in each subclass, or (even better) provide a class specific method, perhaps called wishList, that provides the appropriate parameters to the method called from the superclass constructor. Thus the above example code could be changed to:

sub new {
    my ($class, $args) = @_;
    my $self = bless({}, $class);
    $self->askSantaFor($class->wishList());
    return $self;
}
[download]

Hope that helps, DJ