Ben Giddings wrote:

>In Java you could check to see if something is of a certain class, but what 
>was more often done was to see if something implemented a certain interface.  
>Implementing an interface was a way of signalling "I declare myself to act 
>like a duck".  And the fact you implemented the interface meant that you had 
>all the necessary features to act like a duck.  You weren't allowed to 
>implement the interface and then only choose certain duck-like features.
>
>It seems to me that duck-typing in Ruby should strive for the same thing.  
>Checking for one method isn't enough, in my opinion.
>
I agree with Ryan's reply to you. If I only need the one method on the 
object I'm interacting with -- should that one call not be allowed 
simply because all of the other methods that I don't need aren't 
consistent with what it *should* be?

-- 

Chris
http://clabs.org/blogki