Since $self->{data} is just an attribute, you can set it to undef after the untie in the child method, and adding an if (defined $self->{data}) {...} around the untie in the parent's DESTROY.

Hope this helps, -gjb-

Thank you! This seems to work. Below is my test code.

use strict;
use warnings;
use Data::Dumper;

my $control = Control->new();
my $app = Control::Main->new( %{$control} );

package Control;
use Data::Dumper;

sub new {
    my $class = shift;
    my $self = bless {}, ref($class) || $class;

    #my $dbh = Area::DB::connect(\$_connected) if !$_connected;
    #tie %{$self->{data}}, "Tie::ODBCSession", $dbh, $session_id;
    $self->{data} = {};

    return $self;
}

sub DESTROY {
    my $self = shift;

    print "Destroying parent:\n";
    print Dumper ($self) . "\n";
}

package Control::Main;
@Control::Main::ISA = qw(Control);
use Data::Dumper;

sub new {
    my $class = shift;
    my %args = @_;
    my $self = {};

    bless $self, $class;

    # initialize with named parameters passed
    %{$self} = map { $_ => $args{$_} } keys(%args);
    
    # store action in the object
    $self->{data}->{action} = "test";
    
    return $self;
}

sub DESTROY {
    my $self = shift;

    $self->{data} = undef;
    print "Destroying child:\n";
    print Dumper ($self) . "\n";

}
[download]

By the sounds of it, you don't need to worry about DESTROY in the child - just call the parent module's DESTROY and let it take care of the untieing of the object and the DB update.

Hope that helps ..
-- Foxcub

That assumes that the data IS shared, and I don't think it is... In this case parent's data is different from child's data.

If that's the case, and you can call the $self->Parent::DESTROY to save the child data, why not undef the parent's data at the same time, and add if defined around the untie?

That way when the DESTROY method gets called for the parent, it finds that the data is undefd, and does nothing.

Alternatively, always untie the parent's data first, then the child's, again testing defined and that should get you round the problem.

Not sure if either of those methodologies are the best, though.

Hope that helps
-- Foxcub