XML Schema: Coding requirements for attribute domain modules
All vocabulary and constraint modules must document their @domains attribute contribution. The OASIS grammar files use a <dita:domainsModule> element to document the contribution; this element is used consistently to make it easy to find values when creating a document type shell. An XML comment or <xs:appinfo> element can also be used.
An attribute domain consists of one file. The file must have a single attribute group
definition that contains the definition of the attribute itself, where the attribute
group is
named attnameAtt-d-attribute.
For example, the @deliveryTarget attribute is defined with the following attribute group:
<xs:attributeGroup name="deliveryTargetAtt-d-attribute">
<xs:attribute name="deliveryTarget" type="xs:string">
<!-- Documentation for attribute -->
</xs:attribute>
</xs:attributeGroup>