DITA 2.0 preview support

DITA Open Toolkit 3.5 provides an initial preview of features for the upcoming OASIS DITA 2.0 specification. This preliminary processing support is provided on the basis of the latest DRAFT versions of the DITA 2.0 DTD and RelaxNG grammar files from OASIS (as of March 2020).

DITA documents that reference the draft grammar files can be parsed, and where features overlap with DITA 1.3, those features will work as expected.

• The new <include> element can be used to reference text or XML content from other files. In addition to the processing mandated by the specification, DITA-OT also supports the character set definition and line range extraction options previously provided for <coderef> elements (see Extended codeblock processing).

• The new @specializations attribute, which replaces the DITA 1.x @domains attribute, can now be used as an alternative method of declaring specialized attributes.

• The @outputclass attribute can now be specified as a flagging behavior in DITAVAL files. This allows you to flag an element with a CSS class keyword that will be added to the @class attribute value in the generated HTML. Output classes allow you to pick up pre-defined styles from existing web frameworks, and are more easily overridden with custom CSS files than the inline @style attributes generated by DITA 1.x flagging options such as @color and @backcolor.

• Titles can now be specified on simple tables, and <simpletable> entries now support row and column spanning attributes.

• Where DITA 1.x defined conflicting @class values for <linktext>, <shortdesc>, and <searchtitle> in maps and topics, the new draft of DITA 2.0 uses the topic-based @class value in all cases. Processing is updated to recognize the updated value when these elements are used in maps.