The hasInstance element specifies that the contained subjects have an INSTANCE-OF relationship with the container subject. In an INSTANCE-OF hierarchy, the child subject is a specific entity or object and the parent subject is a type, kind, or class of entity or object.
Content models
See appendix for information about this element in OASIS document type shells.
Inheritance
- map/topicref subjectScheme/hasInstance
Example
This example specifies that New York City, Reykjavik, and Moscow are each specific instances of a city.
<subjectScheme> <hasInstance> <subjectdef keys="city" navtitle="City"> <subjectdef keys="nyc" navtitle="New York City"/> <subjectdef keys="reykjavik" navtitle="Reykjavik"/> <subjectdef keys="moscow" navtitle="Moscow"/> </subjectdef> </hasInstance> </subjectScheme>
Attributes
The following attributes are available on this element: Universal attribute group, Link relationship attribute group (with a narrowed definition of href, given below), processing-role from Attributes common to many map elements, navtitle from Topicref element attributes group, outputclass, keys, and keyref.
- href
- A pointer to the resource represented by the topicref. See The href attribute for detailed information on supported values and processing implications. References to DITA content cannot be below the topic level: that is, you cannot reference individual elements inside a topic. References to content other than DITA topics should use the format attribute to identify the kind of resource being referenced.