From: Jim Weirich <jweirich@...>
Date: 2003-11-29T04:44:20+09:00
Subject: Re: pre/post question/idea

T. Onoma wrote:
> but can anyone explain why we have pre and post if wrap does them both?

Pre and Post cannot effect the incoming parameters[1], nor can they 
effect the return result.  Wrap can do both.

So, pre/post are "safer" if you don't want to change the semantics of 
the base method (e.g. logging).

-- 
-- Jim Weirich       jweirich@one.net      http://onestepback.org
-----------------------------------------------------------------
"Beware of bugs in the above code; I have only proved it correct,
not tried it." -- Donald Knuth (in a memo to Peter van Emde Boas)

[1] Well actually, I suppose they can effect the parameters if they call 
a method with a side effect method on the parameters.