The architectural attributes specify the version of DITA
that the content supports, identify the DITA domains that are in use by the
content, and provide essential information about specializations that are in
use by the content.
The architectural attributes should not be marked up in the source
DITA map and topic instances. Instead, the values of the architectural
attributes are handled by the processor when the content is processed,
preferably through defaults set in the DTD or Schema declaration.
This practice ensures that the DITA content instances do not specify
invalid values for the architectural attributes.
The architectural attributes are as follows:
- class
- This attribute identifies the specialization modules for the element
type as well as its ancestors. Every DITA element (except the <dita>
element that is used as the root of a ditabase document) has a @class
attribute.
- domains
- This attribute identifies the domain specialization modules used in a map or topic
and, for each
domain module, its module dependencies. The root element of every topic and map
has a @domains attribute.
- DITAArchVersion
- This attribute identifies the version of the DITA architecture used by the DTD or
schema. The
root element of every topic and map has a @DITAArchVersion attribute. The
attribute is declared in a DITA namespace to allow namespace-sensitive tools to
detect DITA markup.
To make the document instance usable in the absence of a DTD or
Schema declaration, a normalization process may set the architectural
attributes in the document instance.
