From: Johannes Schlüter [mailto:johan...@schlueters.de] > Thus having > > function bar(C $c) { > $a = new A(); > $c->foo($a); > } > > might work or might not work as $c might be an instance of D. Thus > breaks the Liskov Substitution Principle > http://en.wikipedia.org/wiki/Liskov_substitution_principle >
Oh, now I see. Thanks fort he example, that helped ;) Christian
