You could use miyagawa's Attribute::Protected module which let's you implement C++/Java style encapsulation on your methods.

package SomeClass;
use Attribute::Protected;

sub new { return bless {}, shift }

sub foo : Public {
    print "am in public foo()\n";
}
sub bar : Private {
    print "am in private bar()\n";
}
qq[end of package];

package main;

$x = SomeClass->new();
$x->foo();             # fine - foo is public
$x->bar();             # dies - bar is private
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HTH

broquaint