You are correct. Your get and set methods will not work. I should have looked closer at the code in the OP and the replies.

This appears to work though.

sub get_hshAgg {
    my $self = shift;
    return $self->{hshAgg};
}

sub set_hshAgg {
    my $self = shift;
    my $hshToAgg = shift;
    $self->{hshAgg} = $hshToAgg;
}

sub run {
    my $self        = Foo->new(@_);
    my %hshToAgg      = ();
    my $class;
    (
     $class,
     %hshToAgg
    ) = @_;

    $self->set_id($intID);
    $self->set_hshAgg(\%hshToAgg);

    use Data::Dumper;
    print Dumper \%hshToAgg;
    print "After instantiation\n";
    my %hshTest = %{$self->get_hshAgg};
    print Dumper \%hshTest;
}
[download]