use strict;
require 'foo_bar.pl';  #currently using require for these
require 'foo_batz.pl'; #intention is to fold them into the 
                       #script after development 
my @Stack = ();
my $type = "Bar" || "Batz";
do_phu($type);

sub do_phu {
    my $class = shift;
    my $temp_obj = Foo::$type->new();
    push( @Stack, $temp_obj ); # point of failure
}