http://qs1969.pair.com?node_id=157174


in reply to Private Class Methods

You could always wait for Perl 6.
class Foo { my method bar {...} }
et viola! only Foos can call bar. Sorry if that's not exactly helpful. The other option is:
sub bar { croak "Oi! You're not a foo!" unless $_[0]->isa(__PACKAGE__); }