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Re: XML Schema Question

From: Joseph M. Reagle Jr. <reagle@w3.org>
Date: Thu, 11 Jan 2001 16:40:25 -0500
Message-Id: <>
To: "Ashok Malhotra" <petsa@us.ibm.com>
Cc: "Martin J. Duerst" <duerst@w3.org>, henry@w3.org, "Michael Sperberg-McQueen" <cmsmcq@w3.org>, xmlschema-dev@w3.org, Brian LaMacchia <bal@microsoft.com>, "Donald Eastlake" <dee3@torque.pothole.com>, <lde008@dma.isg.mot.com>
Hi Ashok. I don't think this would do the trick (they are all optional, but 
there must be one of them because it'd be silly to have their parent be 
empty), plus we couldn't meet the requirments of the SG since they are of 
different types! Regardless, we'll go othe "silly" route, I just wanted to 
make sure I wasn't missing some clever trick.

At 09:31 1/11/2001 -0500, Ashok Malhotra wrote:

>At 01/01/09 18:15 -0500, Joseph M. Reagle Jr. wrote:
> >Is there a more elegant schema representation for the semantic of, "you
> >can have a sequence of the following, and while I don't care which you
> >have (they are all optional) you must have at least one of them."
>I've not been following this thread closely but it seems to me that
>a substitutionGroup would provide the needed semantic.
>Create a substitutionGroup with one of the optional items as
>exemplar.  Put all the other items in the substitutionGroup.
>Define the type to contain one or more or the exemplar.
>This design will allow multiple occurrences of one of the optional items.
>Is this a problem?

Joseph Reagle Jr.
W3C Policy Analyst                mailto:reagle@w3.org
IETF/W3C XML-Signature Co-Chair   http://www.w3.org/People/Reagle/
Received on Thursday, 11 January 2001 16:42:37 UTC

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