use CGI qw(:all);
my $op = param('operation');

my $table = create_dptable TestPkg;
$table->{$op}->() if exists $table->{$op};

##</code><code>##

use CGI qw(:all);
my $op = param('operation');

{
    no strict 'refs';
    TestPkg->$dispatch('Hello!')
        if defined *{"TestPkg::$dispatch"}{CODE};
}

##</code><code>##

my $input = <>;

my $table = create_dptable TestPkg;
$table->{$_}->($input) foreach (keys $table);

##</code><code>##

my $input = <>;

{
    no strict 'refs';
    *{"TestPkg::$_"}{CODE}->($input)
        foreach( grep {    !/^_/
                        && defined *{"TestPkg::$_"}{CODE} }
                 keys %{*{'TestPkg::'}}
        ); 
}