Migrating to release 3.1

DITA-OT 3.1 includes support for DITA 1.3 SVG domain elements, enhanced <codeblock> processing, and incremental improvements to Lightweight DITA processing and PDF output.

Note: This topic provides a summary of changes in DITA-OT 3.1 that may require modifications to custom stylesheets or plug-ins.

Custom if/unless attributes in Ant scripts

Ant scripts for DITA-OT builds now make use of @if:set and @unless:set attributes in the Ant namespace, which can be used to control whether parameters are passed to XSLT modules. These attributes replace custom implementations of if and unless logic introduced before Ant had this capability.

If your plug-ins include Ant scripts that use @if or @unless on <param> elements that pass XSLT parameters, add the following namespace attributes to the root project:
  • xmlns:if="ant:if"
  • xmlns:unless="ant:unless"

In custom Ant build files and in any files that supply parameters to existing DITA-OT XSLT modules, replace all occurrences of if="property" on <param> elements with if:set="property" (and unless → unless:set respectively).

<root xmlns:if="ant:if" xmlns:unless="ant:unless">
  <param name="antProperty" expression="${antProperty}"
         if:set="antProperty"/>
</root>

For more information on passing parameters to existing XSLT steps, see XSLT-parameter extension points.

PDF – Enabling line numbers in codeblocks

The codeblock.generate-line-number template mode default has been changed to check for the show-line-numbers keyword in the @outputclass attribute. Earlier versions of DITA-OT required custom PDF plug-ins to override the template mode to return true().