Name
optional —
optional pattern
Synopsis
element optional
{
(
attribute ns { text }?,
attribute datatypeLibrary { xsd:anyURI }?,
attribute * - (rng:* | local:*) { text }*
),
(
( element * - rng:* { ... }* )
& (
element element { ... }
| element attribute { ... }
| element group { ... }
| element interleave { ... }
| element choice { ... }
| element optional { ... }
| element zeroOrMore { ... }
| element oneOrMore { ... }
| element list { ... }
| element mixed { ... }
| element ref { ... }
| element parentRef { ... }
| element empty { ... }
| element text { ... }
| element value { ... }
| element data { ... }
| element notAllowed { ... }
| element externalRef { ... }
| element grammar { ... }
)+
)
}May be included in
attribute, choice,
define, element,
except, group,
interleave, list,
mixed, oneOrMore,
optional, start,
zeroOrMore
Description
The optional pattern specifies that its
subpatterns considered as an ordered group is optional, i.e., be
matched zero or one times.
Example
<element name="author">
<attribute name="id"/>
<element name="name">
<text/>
</element>
<element name="born">
<text/>
</element>
<optional>
<element name="died">
<text/>
</element>
</optional>
</element>
<element name="name">
<choice>
<text/>
<group>
<element name="first"><text/></element>
<optional>
<element name="middle"><text/></element>
</optional>
<element name="last"><text/></element>
</group>
</choice>
</element>..................Content has been hidden....................
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