package My::Application::Base;
use CGI::Application;
our @ISA = qw( CGI::Application );

sub setup
{
    # Do basic stuff, including run_modes everyone has, like 'redirect
+_login'
}

sub cgiapp_prerun
{
    # Do $dbh and $user setup, including standard cookie handling
}

sub print
{
    my $self = shift;
    my ($display_type, $template_name, @params) = @_;

    # This is my method. I have to potentially display in a number of 
+formats.
    # I use different templating modules to do that, like PDF::Templat
+e or
    # Excel::Template, instead of just HTML::Template. This does that 
+for me.
}

--------

package My::Application::Main;
use My::Application::Base;
our @ISA = qw( My::Application::Base );

sub setup
{
    my $self = shift;

    $self->run_modes([qw(
        login
        validate
        home
        logout
    )];
}

sub login
{
    my $self = shift;
    my ($error) = @_;

    my %params;
    $params{ERROR} = $error if defined $error;

    $self->print(
        'html', 'login',
        %params,
    );
}

sub validate
{
    my $self = shift;

    if (BAD_LOGIN)
    {
        return $self->login($SOME_ERROR);
    }

    # Set the cookie up, and possibly a session. Hand this off
    # to other modules / functions / objects

    $self->home;
}

sub home
{
    my $self = shift;
    $self->print(
        'html', 'home',
    );
}

sub logout
{
    my $self = shift;

    # Destroy the session and the cookie
    $self->print(
        'html', 'logout',
    );
}
[download]

package My::Application::Reports;
use My::Application::Base;
our @ISA = qw( My::Application::Base );

sub setup
{
    my $self = shift;

    $self->runmodes([qw(
        choose
        display
    )]);
}

sub choose
{
    # Display some method of choosing reports, probably with some auth
+orization
    # checks in there
}

sub display
{
    # Do the actual display of the report.
}
[download]