Preface to the DocBook V5.2 Edition

This edition of DocBook 5: The Definitive Guide describes the DocBook V5.2 schema, currently version 5.2.10.

The current O'Reilly edition covers DocBook V5.0, the OASIS Standard.

Summary of Changes in DocBook V5.2

Added a transform attribute to the resource element (as an alternative to grammar).
Removed the grammar attribute from output.
Added a danger admonition.
Added an otherclass attribute to article as an alternative to the enumerated class values.
Added a formalgroup element to contain several formal objects (for example, subfigures in a figure).
Relaxed the content model of abstract to include non-paragraph block elements.
Added multimediaparams to imagedata.
Added a buildtarget inline.
Allow funcdef to contain an explicit void.
Allow paramdef to contain modifiers.
Allow fieldsynopsis, methodsynopsis, and methodparam to contain more than one type.
Extended the content model of type so that it can represent union and intersection types. Added a class attribute to type.
Allow numbered sections (sect1, sect2, etc.) to contain refentry.
Added interface to the enumerated values in the class attribute of systemitem.

The following backwards incompatible changes are planned for DocBook V6.0:

The linking elements will be removed from the content model of biblioid.
The common linking attributes will be removed from indexterm.
The xml:id attribute will be made required on startofrange indexterms.
A Schematron constraint will be added to assert that for every startofrange indexterm there is exactly one endofrange indexterm that points to it.
The language attribute will be removed from address; use xml:lang instead.
The arc and locator elements will be dropped; instead link will be allowed in extendedlink.