Name
optional — Optional information
Synopsis
optional ::=
(text | phrase
db._phrase | replaceable
| Graphic inlines | Indexing inlines | Linking inlines | Ubiquitous inlines)*
Attribute synopsis
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.
Optional arguments in a synopsis
are usually
given special typographic treatment, and often they are surrounded by
square brackets. The optional
tag is expected to
generate the brackets.
Outside a synopsis
, the typographic treatment
of optional
is application specific.
See Also
computeroutput
, constant
, literal
, markup
, option
, parameter
, prompt
, replaceable
, tag
, userinput
, varname
Examples
<article xmlns='http://docbook.org/ns/docbook'> <title>Example optional</title> <synopsis> ls <option>-abcCdfFgilLmnopqrRstux1</option> <optional>names</optional> </synopsis> </article>
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