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Re: [Moderator Action] how to model "at least one element ..."

From: Henry S. Thompson <ht@cogsci.ed.ac.uk>
Date: 09 Mar 2001 16:42:12 +0000
To: Ulrich Mehlhaus <Ulrich.Mehlhaus@ptv.de>
Cc: "'xmlschema-dev@w3.org'" <xmlschema-dev@w3.org>
Message-ID: <f5bwv9yevx7.fsf@cogsci.ed.ac.uk>
The traditional approach to this is ((a,b?)|b).  If you allow either
order then it's ((a,b?)|(b,a?)).  So in XML Schema syntax that's 

 <xs:choice>
  <xs:sequence>
   <xs:element ref="a"/>
   <xs:element ref="b" minOccurs="0"/>
  </xs:sequence>
  <xs:element ref="b"/>
 </xs:choice>

ht
-- 
  Henry S. Thompson, HCRC Language Technology Group, University of Edinburgh
          W3C Fellow 1999--2001, part-time member of W3C Team
     2 Buccleuch Place, Edinburgh EH8 9LW, SCOTLAND -- (44) 131 650-4440
	    Fax: (44) 131 650-4587, e-mail: ht@cogsci.ed.ac.uk
		     URL: http://www.ltg.ed.ac.uk/~ht/
Received on Friday, 9 March 2001 11:42:15 GMT

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