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<html><head>
<META http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>RELAX NG DTD Compatibility</title><link rel="stylesheet" href="tr.css" type="text/css"><meta name="generator" content="DocBook XSL Stylesheets V1.40"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="article"><div class="titlepage"><p class="logo"><a href="http://www.oasis-open.org/"><img src="oasis.png" alt="OASIS" border="0"></a></p><div><h1 class="title"><a name="IDAHAYR"></a>RELAX NG DTD Compatibility</h1></div><div><h2>Committee Specification 3 December 2001</h2></div><div><dl><dt>This version:</dt><dd>Committee Specification: 3 December 2001</dd></dl><dl><dt>Previous versions:</dt><dd>Committee Specification: 7 September 2001</dd></dl></div><div><dl><dt>Editors:</dt><dd>James Clark <tt><<a href="mailto:[email protected]">[email protected]</a>></tt>, MURATA Makoto <tt><<a href="mailto:[email protected]">[email protected]</a>></tt></dd></dl></div><div></div><div><div class="legalnotice"><p>Copyright © The Organization for the Advancement of
Structured Information Standards [OASIS] 2001. All Rights
Reserved.</p><p>This document and translations of it may be copied and furnished
to others, and derivative works that comment on or otherwise explain
it or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any kind,
provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to OASIS, except as needed for the
purpose of developing OASIS specifications, in which case the
procedures for copyrights defined in the OASIS Intellectual Property
Rights document must be followed, or as required to translate it into
languages other than English.</p><p>The limited permissions granted above are perpetual and will not
be revoked by OASIS or its successors or assigns.</p><p>This document and the information contained herein is provided
on an "AS IS" basis and OASIS DISCLAIMS ALL WARRANTIES,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE
USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY
IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR
PURPOSE.</p></div></div><div><hr><div class="abstract"><h2><a name="IDAMCYR"></a>Abstract</h2><p>This specification defines datatypes and annotations for use in
<a href="#spec" title="[RELAX NG]">[RELAX NG]</a> schemas. The purpose of these datatypes and
annotations is to support some of the features of XML 1.0 DTDs that
are not supported directly by RELAX NG.</p></div></div><div><div class="legalnotice"><h2>Status of this Document</h2><p>This Committee Specification was approved for publication by the
OASIS RELAX NG technical committee. It is a stable document which
represents the consensus of the committee. Comments on this document
may be sent to <a href="mailto:[email protected]" target="_top">[email protected]</a>.</p><p>A list of known errors in this document is available at <a href="http://www.oasis-open.org/committees/relax-ng/compatibility-20011203-errata.html" target="_top">http://www.oasis-open.org/committees/relax-ng/compatibility-20011203-errata.html</a>.</p></div></div></div><div class="toc"><h2>Table of Contents</h2><dl><dt>1 <a href="#IDACDYR">Introduction</a></dt><dd><dl><dt>1.1 <a href="#IDABEYR">Example</a></dt><dt>1.2 <a href="#IDAPEYR">Infoset modification</a></dt><dt>1.3 <a href="#IDA0EYR">Ambiguity</a></dt></dl></dd><dt>2 <a href="#IDA2FYR">Conformance</a></dt><dt>3 <a href="#default-value">Attribute default values</a></dt><dt>4 <a href="#id">ID, IDREF and IDREFS</a></dt><dt>5 <a href="#IDAC1YR">Documentation</a></dt></dl><h3>Appendixes</h3><dl><dt>A <a href="#IDAP2YR">RELAX NG schema</a></dt><dt><a href="#IDA12YR">References</a></dt></dl></div><hr><div class="section"><a name="IDACDYR"></a><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="IDACDYR"></a>1. Introduction</h2></div></div><p>RELAX NG <a href="#spec" title="[RELAX NG]">[RELAX NG]</a> provides two mechanisms for
extensibility:</p><div class="itemizedlist"><ul><li><a name="IDALDYR"></a>RELAX NG schemas can reference external
libraries of datatypes;</li><li><a name="IDAODYR"></a>in a RELAX NG schema, RELAX NG-defined elements can be
annotated with child elements and attributes from other
namespaces.</li></ul></div><p>The goal of this specification is to facilitate transition from
XML 1.0 DTDs to RELAX NG schemas by using these extensibility
mechanisms to support some of the features of XML 1.0 DTDs that are
not supported by RELAX NG.</p><p>The annotations defined in this specification have the namespace
URI:</p><pre class="programlisting">http://relaxng.org/ns/compatibility/annotations/1.0</pre><p>This rest of this specification follows the convention of using
the prefix <tt>a</tt> to refer to this namespace URI.</p><p>Annotations with the above namespace URI can be used in
conjunction with annotations with other namespace URIs. Annotations
with other namespace URIs are allowed wherever <a href="#spec" title="[RELAX NG]">[RELAX NG]</a>
specifies that they are allowed.</p><div class="section"><a name="IDABEYR"></a><div class="titlepage"><div><h3 class="title"><a name="IDABEYR"></a>1.1. Example</h3></div></div><p>The following DTD</p><pre class="programlisting"><!DOCTYPE employees [
<!-- A list of employees. -->
<!ELEMENT employees (employee*)>
<!-- An individual employee. -->
<!ELEMENT employee (#PCDATA)>
<!ATTLIST employee
id ID #REQUIRED
manages IDREFS #IMPLIED
managedBy IDREF #IMPLIED
country (US|JP) "US"
>
]></pre><p>could be translated to the following RELAX NG schema:</p><pre class="programlisting"><element name="employees"
xmlns="http://relaxng.org/ns/structure/1.0"
xmlns:a="http://relaxng.org/ns/compatibility/annotations/1.0"
datatypeLibrary="http://relaxng.org/ns/compatibility/datatypes/1.0">
<a:documentation>A list of employees.</a:documentation>
<zeroOrMore>
<element name="employee">
<a:documentation>An individual employee.</a:documentation>
<attribute name="id">
<data type="ID"/>
</attribute>
<optional>
<attribute name="manages">
<data type="IDREFS"/>
</attribute>
</optional>
<optional>
<attribute name="managedBy">
<data type="IDREF"/>
</attribute>
</optional>
<optional>
<attribute name="country" a:defaultValue="US">
<choice>
<value>US</value>
<value>JP</value>
</choice>
</attribute>
</optional>
<text/>
</element>
</zeroOrMore>
</element></pre></div><div class="section"><a name="IDAPEYR"></a><div class="titlepage"><div><h3 class="title"><a name="IDAPEYR"></a>1.2. Infoset modification</h3></div></div><p>RELAX NG itself performs only validation: it does not change the
infoset <a href="#infoset" title="[XML Infoset]">[XML Infoset]</a> of an XML document. Most of the
features of XML 1.0 DTDs that are not supported by RELAX NG involve
modification to the infoset. In XML 1.0, validation and infoset
modification are combined in a monolithic XML processor. It is a goal
of this specification to provide a clean separation between validation
and infoset modification, so that a wide variety of implementation
scenarios are possible. In particular, it should be possible to make
the infoset modifications either before performing RELAX NG validation
or after performing RELAX NG validation or without performing RELAX NG
validation at all. It should also be possible for an implementation
of this specification not to modify the infoset at all and instead
provide the application with a description of the modifications
implied by the annotations, independently of any particular
instance.</p><p>This specification does not provide any support for features of
XML 1.0 DTDs, such as entity declarations, that cannot be cleanly
separated from validation.</p></div><div class="section"><a name="IDA0EYR"></a><div class="titlepage"><div><h3 class="title"><a name="IDA0EYR"></a>1.3. Ambiguity</h3></div></div><p>In an XML 1.0 document that is valid with respect to a DTD, each
element or attribute in the instance has a unique corresponding
element or attribute declaration in the DTD. With RELAX NG this is
not always the case: it may be ambiguous which
<tt>element</tt> or <tt>attribute</tt> pattern any
particular element or attribute in the instance matches. In addition,
it is non-trivial to determine when a RELAX NG schema is ambiguous. A
further complication is that even when cases where it is not
ambiguous, it may require multiple passes or lookahead to determine
which <tt>element</tt> or <tt>attribute</tt>
pattern a particular element or attribute matches. Detecting this
situation is also non-trivial.</p><p>Some features of XML 1.0 DTDs, in particular default attribute
values and ID/IDREF/IDREFS validation, depend crucially on this
unambiguous correspondence between elements or attributes in the
instance and their corresponding declarations. In order to support
these features in RELAX NG schemas by means of datatypes and
annotations, it is therefore necessary to impose restrictions on the
use of these datatypes and annotations. The goals in framing these
restrictions were as follows:</p><div class="orderedlist"><ol type="1"><li><a name="IDAKFYR"></a>It must be possible to determine whether a schema
satisfies the restrictions independently of any particular
instance.</li><li><a name="IDANFYR"></a>Processing of the instance must not require lookahead
or multiple passes.</li><li><a name="IDAQFYR"></a>The modified infoset must be XML 1.0 compatible: it
must be an infoset that could have been produced by a validating XML
1.0 parser for some DTD.</li><li><a name="IDATFYR"></a>Implementation of the restrictions should be
straightforward.</li><li><a name="IDAWFYR"></a>The restrictions should not be any more restrictive
than necessary.</li></ol></div></div></div><div class="section"><a name="IDA2FYR"></a><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="IDA2FYR"></a>2. Conformance</h2></div></div><p>This specification defines three features:</p><div class="itemizedlist"><ul><li><a name="IDACGYR"></a>attribute default values</li><li><a name="IDAFGYR"></a>ID/IDREF/IDREFS</li><li><a name="IDAIGYR"></a>documentation</li></ul></div><p>Conformance is defined separately for each feature. A
conformant implementation can support any combination of features. For
each feature, this specification defines</p><div class="itemizedlist"><ul><li><a name="IDAPGYR"></a>a <i>compatibility</i> property; this
is a property that may hold for a correct RELAX NG schema; it is
analogous to correctness for RELAX NG;</li><li><a name="IDAUGYR"></a>a <i>soundness</i> relationship; this
is a relationship that may hold between a RELAX NG schema for which
the compatibility property holds and an XML instance; it is analogous
to validity for RELAX NG;</li><li><a name="IDAZGYR"></a>for an instance and schema between which the soundness
relationship holds, a modification of the infoset of the instance;
there is nothing analogous to this in RELAX NG.</li></ul></div><p>For each feature, there are two levels of conformance.</p><div class="orderedlist"><ol type="1"><li><a name="IDAAHYR"></a>Level 1 is similar to RELAX NG conformance. It has
two parts: determining whether the compatibility property holds of a
schema, and determining whether the soundness relationship holds
between a compatible schema and an instance.</li><li><a name="IDADHYR"></a>Level 2 requires that an implementation provide
information about the modification of the infoset defined for the
feature. An implementation can provide the application either with a
modified infoset or with sufficient information that would allow the
application to modify the infoset itself.</li></ol></div><p>The following table shows which aspects of conformance are
applicable to each feature:</p><div class="informaltable" id="IDAJHYR"><a name="IDAJHYR"></a><table border="1"><colgroup><col><col><col><col></colgroup><thead><tr><th>Feature</th><th>Compatibility</th><th>Soundness</th><th>Infoset modification</th></tr></thead><tbody><tr><td>attribute default values</td><td>yes</td><td>no</td><td>yes</td></tr><tr><td>ID/IDREF/IDREFS</td><td>yes</td><td>yes</td><td>yes</td></tr><tr><td>documentation</td><td>yes</td><td>no</td><td>no</td></tr></tbody></table></div><p>A conformant implementation may support different features at
different levels.</p><p>A conformant implementation may be an integral part of a RELAX
NG validator or may be a separate software module.</p><p>Note that compatibility does not affect RELAX NG correctness.
Thus, a conforming RELAX NG validator is required to be able to
validate an instance against a correct RELAX NG schema even if that
schema is not compatible with one or more of the features defined in
this specification. Furthermore, soundness is completely independent
of validity. A conforming RELAX NG validator must be able to determine
whether an instance is valid with respect to a correct RELAX NG schema
regardless of whether it is sound with respect to that schema for any
of the features defined in this specifcation. A conforming
implementation of a feature defined by this specification must be able
to determine whether a instance is sound with respect to a compatible
schema, regardless of whether the instance is valid with respect to
that schema.</p></div><div class="section"><a name="default-value"></a><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="default-value"></a>3. Attribute default values</h2></div></div><p>This feature is specified by an annotation attribute. An
<tt>a:defaultValue</tt> attribute on a RELAX NG
<tt>attribute</tt> element specifies the default value for
the attribute.</p><p>A correct RELAX NG schema is compatible with this feature if
after schema simplification, for each <tt>attribute</tt>
element that has an <tt>a:defaultValue</tt> attribute, all
of the following hold:</p><div class="itemizedlist"><ul><li><a name="IDAZRYR"></a>its first child is a <tt>name</tt>
element</li><li><a name="IDA4RYR"></a>the first child of the containing
<tt>element</tt> element is a <tt>name</tt>
element</li><li><a name="IDAFSYR"></a>the value of the <tt>a:defaultValue</tt>
attribute matches the pattern contained in the
<tt>attribute</tt> element</li><li><a name="IDAMSYR"></a>the pattern in the <tt>attribute</tt>
element does not contain a <tt>data</tt> or
<tt>value</tt> element with a context-dependent datatype; a
context-dependent datatype is one for which there is a string for
which the datatypeAllows function (defined in <a href="#spec" title="[RELAX NG]">[RELAX NG]</a>)
returns both true and false according to the context</li><li><a name="IDAYSYR"></a>any ancestor that is a <tt>choice</tt>
element has one child that is an <tt>empty</tt>
element</li><li><a name="IDA5SYR"></a>it has at least one <tt>choice</tt>
ancestor</li><li><a name="IDAETYR"></a>if the containing definition competes with another
definition, then that other definition also contains an
<tt>attribute</tt> element with the same name and with an
<tt>a:defaultValue</tt> attribute with the same
value. A definition<pre class="programlisting"><define name="<i><tt>ln1</tt></i>">
<element>
<i><tt>nc1</tt></i>
<i><tt>p1</tt></i>
</element>
</define></pre><p>competes with a definition</p><pre class="programlisting"><define name="<i><tt>ln2</tt></i>">
<element>
<i><tt>nc2</tt></i>
<i><tt>p2</tt></i>
</element>
</define></pre><p>if there is a name <i><tt>n</tt></i> that belongs to
both <i><tt>nc1</tt></i> and
<i><tt>nc2</tt></i>.</p></li></ul></div><p>Schema simplification as defined in <a href="#spec" title="[RELAX NG]">[RELAX NG]</a>
removes all foreign attributes as well as foreign elements. However,
when checking compatibility of a schema with this feature, schema
simplification must preserve <tt>a:defaultValue</tt>
attributes on <tt>attribute</tt> elements.</p><p>There is no soundness relationship for this feature.</p><p>The modification of the infoset for this feature adds attribute
information items to element information items. An attribute
information item with [local name] <i><tt>x</tt></i>,
[namespace name] <i><tt>y</tt></i> and [normalized value]
<i><tt>z</tt></i> is added to an element information item
<i><tt>e</tt></i>, if and only if:</p><div class="itemizedlist"><ul><li><a name="IDA2UYR"></a><i><tt>e</tt></i> does not already have any attribute
information item with [local name] <i><tt>x</tt></i> and
[namespace name] <i><tt>y</tt></i>, and</li><li><a name="IDAFVYR"></a>after schema simplification, the schema contains an
<tt>attribute</tt> element with<div class="itemizedlist"><ul><li><a name="IDALVYR"></a>a <tt>name</tt> child with content
<i><tt>x</tt></i> and an <tt>ns</tt> attribute
with value <i><tt>y</tt></i>,</li><li><a name="IDAWVYR"></a>an <tt>a:defaultValue</tt>
attribute with value <i><tt>z</tt></i>, and</li><li><a name="IDA3VYR"></a>a containing <tt>element</tt> element that
has a <tt>name</tt> child with content equal to the [local
name] of <i><tt>e</tt></i> and an <tt>ns</tt>
attribute with value equal to the the [namespace name] of
<i><tt>e</tt></i>.</li></ul></div></li></ul></div></div><div class="section"><a name="id"></a><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id"></a>4. ID, IDREF and IDREFS</h2></div></div><p>A RELAX NG schema makes use of this feature by using datatypes.
Each datatype is associated with an <i>ID-type</i>,
which is one of ID, IDREF or IDREFS or null. The datatype library with
URI</p><pre class="programlisting">http://relaxng.org/ns/compatibility/datatypes/1.0</pre><p>contains datatypes named <tt>ID</tt>,
<tt>IDREF</tt> and <tt>IDREFS</tt> associated with
ID-types of ID, IDREF and IDREFS respectively. The datatypes in other
datatype libraries are associated with a null ID-type, unless the
datatype library specifies otherwise.</p><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title"><a name="IDAAXYR"></a>Note</h3><p><a href="#guidelines" title="[Guidelines]">[Guidelines]</a> recommends that the
<tt>ID</tt>, <tt>IDREF</tt> and
<tt>IDREFS</tt> datatypes of <a href="#xmlschema-2" title="[W3C XML Schema Datatypes]">[W3C XML Schema Datatypes]</a>
should have ID-types ID, IDREF, and IDREFS respectively.</p></div><p>A RELAX NG schema is compatible with this feature if and only
if, after schema simplification, for each <tt>data</tt> or
<tt>value</tt> element that specifies a datatype associated
with a non-null ID-type, all of the following hold:</p><div class="itemizedlist"><ul><li><a name="IDAWXYR"></a>its parent is an <tt>attribute</tt>
element</li><li><a name="IDA1XYR"></a>the first child of its <tt>attribute</tt>
parent is a <tt>name</tt> element</li><li><a name="IDAFYYR"></a>the first child of the <tt>element</tt>
ancestor is a <tt>name</tt> element</li><li><a name="IDAMYYR"></a> if its <tt>attribute</tt> parent has any
competing <tt>attribute</tt> elements, then each such
competing <tt>attribute</tt> element has a
<tt>data</tt> or <tt>value</tt> child specifying a
datatype associated with the same ID-type. Two attribute
elements<pre class="programlisting"><attribute> <i><tt>nc1</tt></i> <i><tt>p1</tt></i> </attribute></pre><p>and</p><pre class="programlisting"><attribute> <i><tt>nc2</tt></i> <i><tt>p2</tt></i> </attribute></pre><p>compete if and only if the containing definitions compete and
there is a name <i><tt>n</tt></i> that belongs to both
<i><tt>nc1</tt></i> and <i><tt>nc2</tt></i>. Note
that a definition competes with itself.</p></li></ul></div><p>Thus, a RELAX NG schema that is compatible with this feature
implies a mapping from element/attribute name pairs onto an ID-type,
and hence a mapping from attributes in the instance onto
ID-types.</p><p>An instance is sound for this feature with respect to a
compatible RELAX NG schema if and only if</p><div class="itemizedlist"><ul><li><a name="IDAWZYR"></a>when the value of each attribute in the instance whose
ID-type is not null is split into a sequence of whitespace-separated
tokens, the length of the sequence is 1 if the ID-type is ID or IDREF
and greater than or equal to 1 if the ID-type is
IDREFS, and</li><li><a name="IDAZZYR"></a>no two distinct tokens in attributes of ID-type ID
have the same value, and</li><li><a name="IDA2ZYR"></a>for each token in an attribute of ID-type IDREF or
IDREFS, there is a token in an attribute of ID-type ID with the same
value</li></ul></div><p>The modification of the infoset for this feature changes the
[attribute type] property of attribute information items to
<tt>ID</tt>, <tt>IDREF</tt> or
<tt>IDREFS</tt> according to the ID-type of the attribute
and modifies the [normalized value] by applying the
normalizeWhiteSpace function.</p><p>The semantics needed for RELAX NG validation are defined for
the datatype library</p><pre class="programlisting">http://relaxng.org/ns/compatibility/datatypes/1.0</pre><p>as follows:</p><div class="itemizedlist"><ul><li><a name="IDAP0YR"></a>for <tt>ID</tt> and <tt>IDREF</tt>
a string is an allowed representation if it is a single NCName (as
defined in <a href="#xml-names" title="[XML Namespaces]">[XML Namespaces]</a>) with optional leading and
trailing whitespace; for <tt>IDREFS</tt> a string is an
allowed representation if it is a a whitespace-separated list of one
or more NCNames;</li><li><a name="IDA10YR"></a>values are tested for equality in the same way as for
the builtin <tt>token</tt> datatype</li></ul></div></div><div class="section"><a name="IDAC1YR"></a><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="IDAC1YR"></a>5. Documentation</h2></div></div><p>The <tt>a:documentation</tt> element can be used to
specify human-readable documentation. The functionality provided by
an <tt>a:documentation</tt> element in a RELAX NG schema
would be provided by a comment in an XML 1.0 DTD. The
<tt>a:documentation</tt> element contains text specifying
documentation. It can also have namespace-qualified attributes such as
<tt>xml:lang</tt>.</p><p>If an <tt>a:documentation</tt> element does not have a
preceding sibling element from the RELAX NG namespace, then the
specified documentation applies to the parent element. Otherwise, the
specified documentation applies to the nearest preceding sibling
element from the RELAX NG namespace. There may be multiple
<tt>a:documentation</tt> elements specifying documentation
that apply to the same RELAX NG element.</p><p>A correct RELAX NG schema is compatible with this feature if and
only if, for each <tt>a:documentation</tt> element, all of
the following hold:</p><div class="itemizedlist"><ul><li><a name="IDA01YR"></a>it does not have any child elements</li><li><a name="IDA31YR"></a>it does not have any attribute whose namespace URI is
the empty string, the RELAX NG namespace URI or the compatibility
annotations namespace URI</li><li><a name="IDAA2YR"></a>if it has a preceding sibling element from the RELAX
NG namespace, then the nearest such preceding sibling element is an
element that does not allow child elements
(i.e. <tt>value</tt>, <tt>param</tt> or
<tt>name</tt>)</li></ul></div><p>There is no soundness relationship for this feature.</p><p>There is no infoset modification for this feature.</p></div><div class="appendix"><h2 class="title" style="clear: both"><a name="IDAP2YR"></a>A. RELAX NG schema</h2><p>A RELAX NG schema that is compatible with the features of this
specification must, in addition to being valid with respect to the
RELAX NG schema for RELAX NG specified in <a href="#spec" title="[RELAX NG]">[RELAX NG]</a>, be
valid with respect to the following schema:</p><pre><grammar xmlns="http://relaxng.org/ns/structure/1.0"
xmlns:a="http://relaxng.org/ns/compatibility/annotations/1.0"
xmlns:rng="http://relaxng.org/ns/structure/1.0">
<start>
<choice>
<ref name="<a href="#:normal">normal</a>"/>
<ref name="<a href="#:attribute">attribute</a>"/>
<ref name="<a href="#:atomic">atomic</a>"/>
</choice>
</start>
<a name=":normal"></a><define name="normal">
<element>
<nsName ns="http://relaxng.org/ns/structure/1.0">
<except>
<name>rng:attribute</name>
<name>rng:value</name>
<name>rng:param</name>
<name>rng:name</name>
</except>
</nsName>
<ref name="<a href="#:normalAtts">normalAtts</a>"/>
<ref name="<a href="#:normalContent">normalContent</a>"/>
</element>
</define>
<a name=":attribute"></a><define name="attribute">
<element name="rng:attribute">
<ref name="<a href="#:normalAtts">normalAtts</a>"/>
<optional>
<attribute name="a:defaultValue">
<text/>
</attribute>
</optional>
<ref name="<a href="#:normalContent">normalContent</a>"/>
</element>
</define>
<a name=":atomic"></a><define name="atomic">
<element>
<choice>
<name>rng:value</name>
<name>rng:param</name>
<name>rng:name</name>
</choice>
<ref name="<a href="#:normalAtts">normalAtts</a>"/>
<text/>
</element>
</define>
<a name=":normalAtts"></a><define name="normalAtts">
<zeroOrMore>
<attribute>
<anyName>
<except>
<nsName ns="http://relaxng.org/ns/compatibility/annotations/1.0"/>
</except>
</anyName>
<text/>
</attribute>
</zeroOrMore>
</define>
<a name=":normalContent"></a><define name="normalContent">
<interleave>
<zeroOrMore>
<ref name="<a href="#:foreign">foreign</a>"/>
</zeroOrMore>
<group>
<zeroOrMore>
<ref name="<a href="#:doc">doc</a>"/>
</zeroOrMore>
<zeroOrMore>
<choice>
<group>
<ref name="<a href="#:atomic">atomic</a>"/>
<zeroOrMore>
<ref name="<a href="#:doc">doc</a>"/>
</zeroOrMore>
</group>
<ref name="<a href="#:attribute">attribute</a>"/>
<ref name="<a href="#:normal">normal</a>"/>
</choice>
</zeroOrMore>
</group>
</interleave>
</define>
<a name=":foreign"></a><define name="foreign">
<element>
<anyName>
<except>
<nsName ns="http://relaxng.org/ns/structure/1.0"/>
<nsName ns="http://relaxng.org/ns/compatibility/annotations/1.0"/>
</except>
</anyName>
<ref name="<a href="#:any">any</a>"/>
</element>
</define>
<a name=":any"></a><define name="any">
<zeroOrMore>
<choice>
<attribute>
<anyName/>
<text/>
</attribute>
<element>
<anyName/>
<ref name="<a href="#:any">any</a>"/>
</element>
<text/>
</choice>
</zeroOrMore>
</define>
<a name=":doc"></a><define name="doc">
<element name="a:documentation">
<zeroOrMore>
<attribute>
<anyName>
<except>
<nsName ns="http://relaxng.org/ns/structure/1.0"/>
<nsName ns="http://relaxng.org/ns/compatibility/annotations/1.0"/>
<nsName ns=""/>
</except>
</anyName>
<text/>
</attribute>
</zeroOrMore>
<text/>
</element>
</define>
</grammar>
</pre></div><div id="IDA12YR" class="bibliography"><div class="titlepage"><div><h2 class="title"><a name="IDA12YR"></a>References</h2></div></div><dl><dt>Guidelines</dt><dd id="guidelines" class="bibliomixed"><a name="guidelines"></a>James Clark, Kohsuke
KAWAGUCHI, editors. <span class="citetitle"><i><a href="http://www.oasis-open.org/committees/relax-ng/xsd.html" target="_top">Guidelines
for using W3C XML Schema Datatypes with RELAX NG</a></i></span>.
OASIS, 2001.</dd><dt>RELAX NG</dt><dd id="spec" class="bibliomixed"><a name="spec"></a>James Clark, Makoto
MURATA, editors. <span class="citetitle"><i><a href="http://www.oasis-open.org/committees/relax-ng/spec.html" target="_top">RELAX NG
Specification</a></i></span>. OASIS, 2001.</dd><dt>W3C XML Schema Datatypes</dt><dd id="xmlschema-2" class="bibliomixed"><a name="xmlschema-2"></a>Paul V. Biron, Ashok Malhotra, editors.
<span class="citetitle"><i><a href="http://www.w3.org/TR/xmlschema-2/" target="_top">XML Schema Part 2: Datatypes</a></i></span>.
W3C (World Wide Web Consortium), 2001.</dd><dt>XML 1.0</dt><dd id="xml-rec" class="bibliomixed"><a name="xml-rec"></a>Tim Bray,
Jean Paoli, and
C. M. Sperberg-McQueen, Eve Maler, editors.
<span class="citetitle"><i><a href="http://www.w3.org/TR/REC-xml" target="_top">Extensible Markup
Language (XML) 1.0 Second Edition</a></i></span>.
W3C (World Wide Web Consortium), 2000.</dd><dt>XML Infoset</dt><dd id="infoset" class="bibliomixed"><a name="infoset"></a>John Cowan, Richard Tobin,
editors.
<span class="citetitle"><i><a href="http://www.w3.org/TR/xml-infoset/" target="_top">XML
Information Set</a></i></span>.
W3C (World Wide Web Consortium), 2001.</dd><dt>XML Namespaces</dt><dd id="xml-names" class="bibliomixed"><a name="xml-names"></a>Tim Bray,
Dave Hollander,
and Andrew Layman, editors.
<span class="citetitle"><i><a href="http://www.w3.org/TR/REC-xml-names/" target="_top">Namespaces in
XML</a></i></span>.
W3C (World Wide Web Consortium), 1999.</dd></dl></div></div></body></html>