From: Ryan Pavlik <rpav@...>
Date: 2003-11-06T15:52:34+09:00
Subject: Re: Managing metadata about attribute types

On Thu, 6 Nov 2003 15:32:57 +0900
David Naseby <david.naseby@eonesolutions.com.au> wrote:

<snip> 
> Then the 18th century rolls around, and the platypus emerges. Its certainly
> not a Waterfowl, but it does have a bill and swims, and it would benefit
> from your code. But it is blocked from using it. Your strong typing reduced
> your codes benefit to a use you could not have *possibly* have predicted. 
<snip>

A platypus is most certainly not a duck---it neither walks like a duck
nor quacks like a duck.  If you want it walking and quacking like a
duck, then a platypus will not fit the bill. (*groans* ;)

If you just want it to be a BilledAnimal, then make a BilledAnimal
mixin, and give it to Duck and Platypus.  Simple.

-- 
Ryan Pavlik <rpav@mephle.com>

"Do not question wizards, for they are quick to
 turn you into a toad." - 8BT