3.6.1.2 <schemeref>
A <schemeref> element references another subject
scheme map. Typically, the referenced subject scheme defines a base set of controlled values;
the referencing map then extends the base set of controlled values. The values specified in the
subject scheme maps are merged; the result is equivalent to specifying all of the values in a
single map.
Content models
See appendix for information about this element in OASIS document type shells.
Inheritance
- map/topicref subjectScheme/schemeref
See subjectScheme .
Attributes
The following attributes are available on this element: Universal attribute group
, Link relationship attribute group
(with narrowed definitions of
@href, @format, and @type, given below),
@navtitle and @query 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@formatattribute to identify the kind of resource being referenced. -
@format - On this element the
@formatattribute sets a default value of "ditamap", because the purpose of the element is to reference a ditamap document. Otherwise, the attribute is the same as described in Link relationship attribute group . -
@type - Describes the target of a reference. For the
<schemeref>element, this value defaults to "scheme", because the element is expected to point to another subject scheme.