An example of Context-sensitive Content Models in Relax NG
At several places you can read, that Relax NG
supports context-sensitive content models.
I needed a small example of that feature, that fits on a presentation slide.
Since I couldn't find one within 5 minutes, I wrote my own. Maybe you can use it.
A Relax-NG-Schema
The following Schema defines an element type d
with a content model,
that depends on the ancestor context in which the element d
is actually placed. Please note that the content model of c
is always d
.
<grammar xmlns="http://relaxng.org/ns/structure/1.0">
<start>
<element name="root">
<choice>
<element name="a">
<element name="c">
<ref name="d-descendant-of-a"></ref>
</element>
</element>
<element name="b">
<element name="c">
<ref name="d-descendant-of-b"></ref>
</element>
</element>
</choice>
</element>
</start>
<define name="d-descendant-of-a">
<element name="d">
<element name="e"></element>
</element>
</define>
<define name="d-descendant-of-b">
<element name="d">
<element name="f"></element>
</element>
</define>
</grammar> Two valid instances
The following two XML instances both validate against the above schema.
test1.xml:
test2.xml:
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Stefan Mintert, $Date: 2005/06/10 14:09:57 $ (UTC)
