optional
optional — Optional information.
Synopsis
optional ::=
- Zero or more of:
- text
optional
- Graphic inlines
- Indexing inlines
- Linking inlines
- Ubiquitous inlines
abbrev
acronym
alt
anchor
biblioref
coref
date
emphasis
(db._emphasis)firstterm
(db._firstterm)footnote
footnoteref
foreignphrase
(db._foreignphrase)glossterm
(db._glossterm)indexterm
(db.indexterm.endofrange)indexterm
(db.indexterm.singular)indexterm
(db.indexterm.startofrange)inlinemediaobject
link
olink
phrase
(db._phrase)quote
(db._quote)remark
subscript
superscript
trademark
wordasword
xref
Attributes
Common attributes and common linking attributes.
No additional attributes.
Description
The optional
element indicates that a specified
argument, option, or other text is optional. The precise meaning of
optional
varies according to the application or process
being documented.
Processing expectations
Formatted inline.
Attributes
Common attributes and common linking attributes.
- any attribute
Any attribute in any other explicit namespace
Parents
These elements contain optional
: bridgehead
, citation
, citetitle
, contrib
, emphasis
(db.emphasis), entry
, firstterm
(db.firstterm), glosssee
, glossseealso
, glossterm
(db.glossterm), inlinestagedir
, line
, link
, literallayout
, member
, meta
(db.meta.content), olink
, optional
, orgdiv
, para
, phrase
(db.phrase), primary
, quote
(db.quote), remark
, secondary
, see
, seealso
, simpara
, subtitle
, term
, termdef
, tertiary
, title
, titleabbrev
.
Children
The following elements occur in optional
: text, abbrev
, acronym
, alt
, anchor
, biblioref
, coref
, date
, emphasis
(db._emphasis), firstterm
(db._firstterm), footnote
, footnoteref
, foreignphrase
(db._foreignphrase), glossterm
(db._glossterm), indexterm
(db.indexterm.endofrange), indexterm
(db.indexterm.singular), indexterm
(db.indexterm.startofrange), inlinemediaobject
, link
, olink
, optional
, phrase
(db._phrase), quote
(db._quote), remark
, subscript
, superscript
, trademark
, wordasword
, xref
.
See Also
Related elements: literal
.
Examples
1 |<article xmlns='http://docbook.org/ns/docbook'>
|<title>Example optional</title>
||
<synopsis>
5 |ls <option>-abcCdfFgilLmnopqrRstux1</option>
|<optional>names</optional>
|</synopsis>
||
</article>
||
ls
|-abcCdfFgilLmnopqrRstux1
names