Purpose of <xs:sequence/>

Hi Chaps,

I am having trouble understanding what the purpose of an empty sequence
declaration is?

e.g. - <xs:sequence/> or <xsd:sequence/>

Certainly it seems to have no relevance in a document instance of that
Schema.

For example in one of the Schemas here we have global declarations like
this -

<xs:element name="Classifier" type="Classifier"/>
<xs:complexType name="Classifier">
	<xs:sequence/>
	<xs:attribute name="pid" type="xs:string" use="required"/>
</xs:complexType>

<xs:element name="Reference" type="Reference"/>
<xs:complexType name="Reference">
	<xs:sequence/>
</xs:complexType>


There is probably some design subtlety that I am missing, can someone
explain it?

Thanks

Adam Retter

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Received on Thursday, 19 June 2008 12:27:54 UTC