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Re: DAML-S: Conditional E/Os

From: Mark Burstein <burstein@bbn.com>
Date: Mon, 26 May 2003 15:10:15 -0400
Message-Id: <>
To: mithun sheshagiri <mits1@cs.umbc.edu>
Cc: www-ws@w3.org
I see where you are going with this. I guess, to some degree you are 
correct that the truth value of this term
is not useful in this context, at least not for an isolated service request.
However, it might be the case that there were other ways for the client to know
whether the book was in stock, and this might lead to the conclusion that 
the service was not useful in some cases -
(for some books). Suppose, for example, another service provided by this 
provider was an "in stock' query. Or suppose that the requester routinely 
tried a couple times before giving up. It would be good to establish that 
the reason for failure was such that the condition dictating the failure 
outcome existed so that the requester didn't try again to buy that 
particular book from that site.

At 08:55 PM 5/25/2003 -0400, mithun sheshagiri wrote:
>Hi All,
>               Lets take the example of ExpressCongoBuy atomic service. 
> This service has 2 conditional  outputs- congoOrderShippedOut and 
> congoOutOfStockOutput. Only one of these will materialize (depending on 
> the BookInStock and BookOutStock conditions) on service execution.
>In this case what is the use of BookInStock/BookOutStock? The "values" of 
>these variables are not part of the advertisement, since the value depends 
>on congoBuyBookISBN (input). The value of this variable can be known only 
>when the response from service provider is received. Now, if I get the 
>desired output then I won't be interested in BookInStock because I know it 
>is true. If I get the undesired output, then I can use the value of the 
>condition variable to determine whether failure was due to a normal 
>problem (book being out of stock) or a abnormal problem (book was in stock 
>and still the service did  not execute as intended). So, is diagnosis the 
>only purpose of condition variable.
>Mithun Sheshagiri

* Dr. Mark H. Burstein <burstein@bbn.com>
* Director, Human Centered Systems Group
* BBN Technologies
* 10 Moulton Street
* Cambridge, MA 02138
* Tel: 617-873-3861
*  Fax: 617-873-4328
* htttp://daml.bbn.com/burstein
Received on Monday, 26 May 2003 15:10:31 UTC

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