title: Overriding one property for a hierarchy of classes
body: <p>I have a hieraarchy of classes. Root class is abstract, and is called Contact, and it has a property DisplayName. On GUI I have a dropdown where various contacts are listed, using their DisplayName property.
  I have no acess to source code of those classes.</p>
  <p>I want to somehow override Contact.DisplayName property, to make it display something else in my particular scenario. I can not just create subclass of Contact and override property there, because there is whole hierarchy under Contact class. Is there a way to alter a property for whole hierarchy of classes ? Maybe using delegates ?</p>
  <p>I am using exotic programming language called Gosu, but the solution based on some common object oriented language could help me a lot too.</p>