RE: Intepretation of choice compositor and occurence into xml sch ema

Hi Bob,

Thanks four you answer. The usage of choice occurence combined with element
seems to be quite complex. Where can I find a good documentation about its
usage ?

-----Original Message-----
From: Bob Schloss [mailto:rschloss@us.ibm.com]
Sent: mercredi, 4. février 2004 17:53
To: Hess Yvan
Cc: 'xmlschema-dev@w3.org'
Subject: Re: Intepretation of choice compositor and occurence into xml
schema






Hess,

The first content model permits
<document/>

<document><A>..</A></document>
<document><B>..</B></document>
<document><C>..</C></docuemnt>


<document><A>..</A><A>..</A></document>
<document><A>..</A><B>..</B></document>
<document><A>..</A><C>..</C></document>
<document><B>..</B><B>..</B></document>
<document><B>..</B><C>..</C></document>
<document><B>..</B><A>..</A></document>
<document><C>..</C><A>..</A></document>
<document><C>..</C><B>..</B></document>
<document><C>..</C><C>..</C></document>

corresponding to occurs of 0, 1 and 2 for the choice particle.


The middle content model permits

<document/> where every inner occurs is 0

<document><A>..</A></document>
<document><B>..</B></document>
<document><C>..</C><document>
where the outer occurs is 1 and the inner occurs is 1

<document>any sequence of multiple A,B,C tags whatsoever</document>
where the outer occurs is > 1 and the inner occurs is sometimes 0 and
sometimes 1




Your last content model permits

<document/>
where outer occurs was 1 and choice went to element B or element C with
occurs of 0

<document><A>,,</A></document>
<document><B>..</B></document>
<document><B>..</B><B>..</B></document>
<document><B>..</B><B>..</B><B>..</B></document>
<document><C>..</C></document>
where outer occurs was 1

any valid concatentation of the content patterns shown above is permitted,
where occurs > 1



Good luck,
Bob

XML/XSL Transformational Systems - Extensible Technologies
IBM Thomas J Watson Research Center
Yorktown Heights, New York, USA






                                                                           
             Hess Yvan                                                     
             <yvan.hess@imtf.c                                             
             h>                                                         To 
             Sent by:                  "'xmlschema-dev@w3.org'"            
             xmlschema-dev-req         <xmlschema-dev@w3.org>              
             uest@w3.org                                                cc 
                                                                           
                                                                   Subject 
             02/04/2004 11:17          Intepretation of choice compositor  
             AM                        and occurence into xml schema       
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           





It is not clear for me how to interpet attribute elements
minOccurs/maxOccurs into <choice> element having sub-elements that also
have
minOccurs/maxOccurs attributes as for example

Schema 1:
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
elementFormDefault="qualified" attributeFormDefault="unqualified">
   <xs:element name="document">
      <xs:complexType>
         <xs:choice minOccurs="0" maxOccurs="2">
            <xs:element name="A" minOccurs="1" maxOccurs="1"/>
            <xs:element name="B" minOccurs="1" maxOccurs="1" />
            <xs:element name="C" minOccurs="1" maxOccurs="1"/>
         </xs:choice>
      </xs:complexType>
   </xs:element>
</xs:schema>

Schema 2:
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
elementFormDefault="qualified" attributeFormDefault="unqualified">
   <xs:element name="document">
      <xs:complexType>
         <xs:choice minOccurs="1" maxOccurs="unbounded">
            <xs:element name="A" minOccurs="0" maxOccurs="1"/>
            <xs:element name="B" minOccurs="0" maxOccurs="1" />
            <xs:element name="C" minOccurs="0" maxOccurs="1"/>
         </xs:choice>
      </xs:complexType>
   </xs:element>
</xs:schema>

Schema 3:
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
elementFormDefault="qualified" attributeFormDefault="unqualified">
   <xs:element name="document">
      <xs:complexType>
         <xs:choice minOccurs="1" maxOccurs="unbounded">
            <xs:element name="A" minOccurs="1" maxOccurs="1"/>
            <xs:element name="B" minOccurs="0" maxOccurs="3" />
            <xs:element name="C" minOccurs="0" maxOccurs="1"/>
         </xs:choice>
      </xs:complexType>
   </xs:element>
</xs:schema>


I tried to find more information about this subject on the web, but I
didn't
succeed.

Can somebody give me more information about how to interpret schema 1,
schema 2 and schema 3 ?

Thanks for your help.

Yvan

Received on Wednesday, 4 February 2004 12:30:22 UTC