No matter what, I can always decorate your object. Something like: 
package Decorator;

sub new {
    my ($class, $obj) = @_;
    bless \$obj, $class;
}

sub parent { ${$_[0]} }

sub AUTOLOAD {
    our $AUTOLOAD =~ s/([^:])+$/$1/;
    my $self = shift;
    $self->parent->$AUTOLOAD( @_ );
}

[download]

At that point, I can add whatever I want and instead of $self->SUPER::method( @args ), I can just do $self->parent->method( @args );. This "trick" works in every single language and works cross-languages, too. And there's absolutely no way to test for it. None. If I wanted to add child-class data, I could either inside-out or make a hashref or whatever. The possibilities are endless.

My criteria for good software:
  1. Does it work?
  2. Can someone else come in, make a change, and be reasonably certain no bugs were introduced?

In reply to Re: A class that cannot be subclassed. by dragonchild
in thread A class that cannot be subclassed. by kyle

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