Nothing in Perl that I know of will prevent you from inheriting from such an object.

Ehhh… it's actually pretty easy to do in Moose/Moo/Class::Tiny. I mean, it's not rocket science to work around, but this should do the job:

use v5.16;

package Example::Phone {
    use Moo;
    has number => (is => 'ro', required => 1);
    sub call { ... }
    
    # Make final
    sub BUILD {
        my $self = shift;
        die(sprintf '%s is final; %s cannot inherit', __PACKAGE__, ref
+($self))
            unless ref($self) eq __PACKAGE__;
    }
}

package Example::Phone::Mobile {
    use Moo;
    extends 'Example::Phone';
    sub send_sms { ... }
}

my $number1 = Example::Phone->new(number => 1);
my $number2 = Example::Phone::Mobile->new(number => 2); # dies

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In reply to Re^4: Perl OOP by tobyink
in thread Perl OOP by QueenSvetlana

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