Appendix C. DocBook Versions
The OASIS DocBook Technical Committee (TC) is committed to the continued evolution of DocBook. As new needs are expressed by the DocBook-user community, the committee will adapt DocBook so it continues to meet the needs of its users.
The TC observes a very cautious policy regarding changes to the DTD. Backward-incompatible changes can only be introduced:
-
In major releases (4.0, 5.0, 6.0, and so on)
-
Only if the change was described in comments in the DTD in the previous major release
This appendix describes the changes planned for DocBook.
DocBook V3.1
DocBook V3.1, released in February 1999, introduced a number of new elements:
MediaObject
is a wrapper aroundVideoObject
,AudioObject
,ImageObject
, andTextObject
. The purpose ofMediaObject
is twofold: first, it introduces new element types to include video and audio content; second, it provides the option of alternative representations, including text, for objects in a document.MediaObject
s also allowCaption
s that may be longer than a simple title.Parallel to
MediaObject
areInlineMediaObject
, an inline version, andMediaObjectCO
, a media object withCallout
s.For now, media objects and graphics exist together in version 5.0.
Graphic
andInlineGraphic
will be removed from DocBook.A figure wrapper without a title. This element was added largely for symmetry.
An end-of-the-book
Colophon
.Section
is a recursive section. It exists parallel to, and must be used as an alternative to,Sect1
.A set of questions and answers.
The
Constant
inline is for identifying constants. It has aClass
attribute for identifying “limits” as a specific kind of constant.Many authors have requested a tag for identifying variable names. Most often
Literal
(with or without a role) has been chosen as a compromise, but you can't question the utility of identifying variable names, soVarName
was added.A tag for identifying variable values does not seem as necessary. For immutable values, a specific tag other than
Literal
seems unnecessary, andReplaceable
exists for values that are supposed to be filled in by the user.
DocBook V4.1 and DocBook XML V4.1.2
DocBook V4.1 and DocBook XML V4.1.2 became an OASIS Standard in February 2001.
DocBook V4 introduced a number of backward-incompatible changes.
The policy of the DocBook TC is that backward-incompatible changes can only be introduced in a full version release. They must also be described in comments in the DTD at least one full version earlier. In other words, all the planned version 4.0 incompatibilities were announced with version 3.0.
Backward-incompatible changes to DocBook that are planned for version 4.0:
-
The
DocInfo
element will be split out intoChapterInfo
,AppendixInfo
, and so on.ArtHeader
will be renamed toArticleInfo
.SeriesInfo
may be discarded because it has become a special case ofBiblioSet
.BookBiblio
will be discarded in favor of a new, more inclusive, structure forBookInfo
(and forArticleInfo
, whose earlierArtHeader
form containedBookBiblio
). -
The
%article.class;
entity may be removed from theBook
content model, and made part of a new top-level document hierarchy. -
The
%nav.class;
entity, which appears in several divisions, will allowToCchap
instead ofToC
. -
MsgText
will be moved from%tech.char.class;
to a more appropriate parameter entity. -
The following elements will have their content constrained to the
%smallcptr.char.mix;
mixture:Action
,Command
,Database
,Filename
,Hardware
,Interface
,KeyCap
,Literal
,Option
,Parameter
,Property
, andSystemItem
. -
AuthorBlurb
andAffiliation
will be removed from%person.ident.mix;
and a new wrapper element will be created to allow association of those two elements withAuthor
name information. -
Epigraph
will not be appearing inBlockQuote
. -
Comment
will be renamed toRemark
and will be excluded from itself. -
GlossTerm
will be excluded from itself, and may be split into an element that appears in aGlossary
and an element that can appear in the main text. -
The
Subject
attribute onGlossDef
will be renamedKeyword
. -
Two
SegTitle
elements will be required inSegmentedList
. -
Graphic
andInlineGraphic
will be declared EMPTY. This change will require that end tags be removed and that any embedded graphic content be stored outside the SGML source and pointed to from anEntityref
orFileref
attribute. -
The
OptMult
andReqMult
values for theChoice
attribute onGroup
will be removed. Use theRep
attribute instead to indicate that the choice is repeatable. -
The content model group inside
FuncSynopsis
starting withFuncDef
will not be available; you will have to useFuncPrototype
. Also, you will be able to have a mixture ofFuncPrototypes
andFuncSynopsisInfos
(this is not backward-incompatible all by itself). -
The
EnvironVar
andPrompt
values for theClass
attribute onSystemItem
will be eliminated; use theEnVar
andPrompt
elements instead.
DocBook V4.2
DocBook V4.2 fixed a couple of small bugs and introduced a number of new features. Changes in DocBook V4.2 are explained in the DocBook Document Type Version 4.2.
EBNF Module
FIXME: write this section
HTML Forms Module
FIXME: write this section
MathML Module
FIXME: write this section
SVG Module
FIXME: write this section