You will probably get a MessageNotUnderstood exception.  Alternatively,
you can check for the existence of the code before attempting to use it.
You can also handle the MessageNotUnderstood in clever ways.

- Stephen

Huw Evans wrote:
> No evolutionary in that sense, evolutionary in the sense that 
> code is bound 
> into a running program and then at some later stage taken 
> away.  Other code 
> that is bound to it may break if the code is just ripped out 
> of the running 
> system.  I was wondering what squeak did in this case.  Do 
> you know of any 
> documentation for this, perhaps a paper?
> 
> Huw