From dougo@ccs.neu.edu  Wed Dec  5 13:40:42 2001
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From: Doug Orleans <dougo@ccs.neu.edu>
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Date: Wed, 5 Dec 2001 13:40:34 -0500 (EST)
To: Karl Lieberherr <lieber@ccs.neu.edu>
Cc: skotthe@ccs.neu.edu, edwards@intranet.com, johan@ccs.neu.edu,
   john_j_sung@yahoo.com, neerajsangal@mediaone.net, robby@ccs.neu.edu,
   wupc@ccs.neu.edu
Subject: Re: contracts and AOP
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Karl Lieberherr writes:
 > Doug proclaimed the following guidelines:
 > 
 > Adding an aspect should not change (invalidate?)
 > pre- and post- conditions of existing code.
 > 
 > Adding an aspect should lead to a behavioral subtype.

I think "proposed" is a better word than "proclaimed".  Or more like,
"hypothesized".  I think Theo is right, it depends on the aspect.
Perhaps that would be a way to categorize aspects: those that preserve 
contracts and those that invalidate contracts, without making a value 
judgement on the latter category.

--Doug