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<?xml version="1.0"?>
<!-- XML Schema schema for XML Schemas: Part 1: Structures -->
<!-- Note this schema is NOT the normative structures schema - - the
     prose copy in the structures REC is the normative version (which
     shouldn't differ from this one except for this comment and entity
     expansions, but just in case -->
<!DOCTYPE schema PUBLIC "-//W3C//DTD XMLSCHEMA 19991216//EN" "XMLSchema.dtd">
<schema xmlns="http://www.w3.org/1999/XMLSchema" targetNamespace="http://www.w3.org/1999/XMLSchema" blockDefault="#all" elementFormDefault="qualified" version="$Id: XMLSchema.xsd,v 1.5 2000/04/28 13:53:45 ht Exp $">

  <!-- The simpleType element and all of its members are defined
       in XML Schema: Part 2: Datatypes -->

  <include schemaLocation="part2.xsd"/>

  <element name="schemaTop" abstract="true" type="annotated">
   <annotation>
    <documentation>This abstract element defines an equivalence class over the
          elements which occur freely at the top level of schemas.
          These are: datatype, type, element, attributeGroup, group, notation
          All of their types are based on the "annotated" type
          by extension.</documentation>
   </annotation>
  </element>

  <!-- schema element -->

  <simpleType name="formChoice" base="NMTOKEN">
   <annotation>
    <documentation>A utility type, not for public use</documentation>
   </annotation>
   <enumeration value="qualified"/>
   <enumeration value="unqualified"/>
  </simpleType>

  <element name="schema">
    <complexType base="openAttrs" derivedBy="extension" content="elementOnly">
      <sequence>
       <choice minOccurs="0" maxOccurs="unbounded">
        <element ref="include"/>
        <element ref="import"/>
        <element ref="annotation"/>
       </choice>
      <sequence minOccurs="1" maxOccurs="unbounded">
	 <element ref="schemaTop"/>
	 <element ref="annotation" minOccurs="0" maxOccurs="unbounded"/>
      </sequence>
    </sequence>
    <attribute name="targetNamespace" type="uriReference"/>
    <attribute name="version" type="string"/>
    <attribute name="finalDefault" type="derivationSet" use="default" value=""/>
    <attribute name="blockDefault" type="blockSet" use="default" value=""/>
    <attribute name="attributeFormDefault" type="formChoice" use="default" value="unqualified"/>
    <attribute name="elementFormDefault" type="formChoice" use="default" value="unqualified"/>
    <attribute name="id" type="ID"/>
   </complexType>

   <key name="element">
    <selector>element</selector>
    <field>@name</field>
   </key>

   <key name="attribute">
    <selector>attribute</selector>
    <field>@name</field>
   </key>

   <key name="type">
    <selector>complexType|simpleType</selector>
    <field>@name</field>
   </key>
 
   <key name="group">
    <selector>group</selector>
    <field>@name</field>
   </key>
 
   <key name="attributeGroup">
    <selector>attributeGroup</selector>
    <field>@name</field>
   </key>
 
   <key name="notation">
    <selector>notation</selector>
    <field>@name</field>
   </key>

   <key name="identityConstraint">
    <selector>.//key|.//unique|.//keyref</selector>
    <field>@name</field>
   </key>

  </element>

  <!-- for all particles -->
  <attributeGroup name="occurs">
    <attribute name="minOccurs" type="nonNegativeInteger" use="default" value="1"/>
    <attribute name="maxOccurs" type="string">
     <annotation>
      <documentation>allows 'unbounded', so integer won't do</documentation>
     </annotation>
    </attribute>
  </attributeGroup>

  <!-- for element, group and attributeGroup,
               which both define and reference -->
  <attributeGroup name="defRef">
   <attribute name="name" type="NCName"/>
   <attribute name="ref" type="QName"/>
  </attributeGroup>
 
 

  <!-- 'complexType' and 'group' use this -->
  <group name="particle">
   <choice>
   <element name="element" type="localElement"/>
   <element name="group" type="groupRef"/>
   <element ref="all"/>
   <element ref="choice"/>
   <element ref="sequence"/>
   <element ref="any"/>
   </choice>
  </group>

  <group name="nestedParticle">
   <choice>
   <element name="element" type="localElement"/>
   <element name="group" type="groupRef"/>
   <element ref="choice"/>
   <element ref="sequence"/>
   <element ref="any"/>
   </choice>
  </group>
 
  <complexType base="annotated" derivedBy="extension" name="attribute" abstract="true">
   <element name="simpleType" minOccurs="0" type="localSimpleType"/>
   <attributeGroup ref="defRef"/>
   <attribute name="type" type="QName"/>
   <attribute name="use" use="default" value="optional">
    <simpleType base="NMTOKEN">
     <enumeration value="prohibited"/>
     <enumeration value="optional"/>
     <enumeration value="required"/>
     <enumeration value="default"/>
     <enumeration value="fixed"/>
    </simpleType>
   </attribute>
   <attribute name="value" use="optional" type="string"/>
   <attribute name="form" type="formChoice"/>
  </complexType>
 
 <complexType name="topLevelAttribute" base="attribute" derivedBy="restriction">
  <element ref="annotation" minOccurs="0"/>
  <element name="simpleType" minOccurs="0" type="localSimpleType"/>
  <attribute name="ref" use="prohibited"/>
  <attribute name="form" use="prohibited"/>
  <attribute name="use" use="prohibited"/>
  <attribute name="name" use="required" type="NCName"/>
 </complexType>

  <group name="attrDecls">
   <sequence>
    <choice minOccurs="0" maxOccurs="unbounded">
     <element name="attribute" type="attribute"/>
     <element name="attributeGroup" type="attributeGroupRef"/>
    </choice>
    <element ref="anyAttribute" minOccurs="0"/>
   </sequence>
  </group>

 <element name="anyAttribute" type="wildcard"/>

  <!-- types for type -->

  <complexType name="complexType" base="annotated" derivedBy="extension" abstract="true">
   <sequence>
    <choice>
     <element ref="facet" minOccurs="0" maxOccurs="unbounded"/>
         <!-- max 1, min 0, for each facet except pattern, period-->
     <group ref="particle" minOccurs="0" maxOccurs="unbounded"/>
    </choice>
    <group ref="attrDecls"/>
   </sequence>
   <attribute name="name" type="NCName">
    <annotation>
     <documentation>Will be restricted to required or forbidden</documentation>
    </annotation>
   </attribute>
   <attribute name="content">
    <simpleType base="NMTOKEN">
     <enumeration value="elementOnly"/>
     <enumeration value="textOnly"/>
     <enumeration value="mixed"/>
     <enumeration value="empty"/>
    </simpleType>
   </attribute>
   <attribute name="base" type="QName"/>
   <attribute name="derivedBy" type="derivationChoice"/>
   <attribute name="abstract" type="boolean" use="default" value="false"/>
   <attribute name="final" type="derivationSet"/>
   <attribute name="block" type="derivationSet" use="default" value=""/>
  </complexType>
 
  <complexType name="topLevelComplexType" base="complexType" derivedBy="restriction">
   <sequence>
    <element ref="annotation" minOccurs="0"/>
    <choice>
     <element ref="facet" minOccurs="0" maxOccurs="unbounded"/>
         <!-- max 1, min 0, for each facet except pattern, period-->
     <group ref="particle" minOccurs="0" maxOccurs="unbounded"/>
    </choice>
    <group ref="attrDecls"/>
   </sequence>
   <attribute name="name" type="NCName" use="required"/>
  </complexType>
 
  <complexType name="localComplexType" base="complexType" derivedBy="restriction">
   <sequence>
    <element ref="annotation" minOccurs="0"/>
    <choice>
     <element ref="facet" minOccurs="0" maxOccurs="unbounded"/>
         <!-- max 1, min 0, for each facet except pattern, period-->
     <group ref="particle" minOccurs="0" maxOccurs="unbounded"/>
    </choice>
    <group ref="attrDecls"/>
   </sequence>
   <attribute name="name" use="prohibited"/>
  </complexType>
 
  <!-- Top level type element, daughter of schema -->
  <element name="complexType" equivClass="schemaTop" type="topLevelComplexType"/> 
 
  <simpleType name="derivationControls" base="string">
   <enumeration value="#all"/>
   <enumeration value="equivClass"/>
   <enumeration value="extension"/>
   <enumeration value="restriction"/>
  </simpleType>

  <simpleType name="derivationChoiceOrAll" base="derivationControls">
   <annotation>
    <documentation>A utility type, not for public use</documentation>
   </annotation>
   <enumeration value="#all"/>
   <enumeration value="extension"/>
   <enumeration value="restriction"/>
  </simpleType>

  <simpleType name="derivationChoice" base="derivationChoiceOrAll">
   <annotation>
    <documentation>A utility type, not for public use</documentation>
   </annotation>
   <enumeration value="extension"/>
   <enumeration value="restriction"/>
  </simpleType>

  <simpleType name="blockSet" base="derivationControls" derivedBy="list">
   <annotation>
    <documentation>#all or (possibly empty) subset of {equivClass,
extension, restriction}</documentation>
    <documentation>A utility type, not for public use</documentation>
   </annotation>
  </simpleType>

  <simpleType name="derivationSet" base="derivationChoiceOrAll" derivedBy="list">
   <annotation>
    <documentation>#all or (possibly empty) subset of {extension,
restriction}</documentation>
    <documentation>A utility type, not for public use</documentation>
   </annotation>
  </simpleType>

  <!-- The element element can be used either
        at the toplevel to define an element-type binding globally,
        or within a content model to either reference a globally-defined
        element or type or declare an element-type binding locally.
       The ref form is not allowed at the top level -->

  <complexType name="element" base="annotated" derivedBy="extension" abstract="true">
     <choice minOccurs="0">
      <element name="simpleType" type="localSimpleType"/>
      <element name="complexType" type="localComplexType"/>
     </choice>
     <element ref="identityConstraint" minOccurs="0" maxOccurs="unbounded"/>
     <attributeGroup ref="defRef"/>
     <attribute name="type" type="QName"/>
     <attribute name="equivClass" type="QName"/>
     <attributeGroup ref="occurs"/>
     <attribute name="default" type="string"/>
     <attribute name="fixed" type="string"/>
     <attribute name="nullable" type="boolean" use="default" value="false"/>
     <attribute name="abstract" type="boolean" use="default" value="false"/>
     <attribute name="final" type="derivationSet" use="default" value=""/>
     <attribute name="block" type="blockSet" use="default" value=""/>
     <attribute name="form" type="formChoice"/>
  </complexType>
 
  <complexType name="topLevelElement" base="element" derivedBy="restriction">
   <element ref="annotation" minOccurs="0"/>
   <choice minOccurs="0">
      <element name="simpleType" type="localSimpleType"/>
      <element name="complexType" type="localComplexType"/>
   </choice>
   <element ref="identityConstraint" minOccurs="0" maxOccurs="unbounded"/>
   <attribute name="ref" use="prohibited"/>
   <attribute name="form" use="prohibited"/>
   <attribute name="minOccurs" use="prohibited"/>
   <attribute name="maxOccurs" use="prohibited"/>
   <attribute name="name" use="required" type="NCName"/>
  </complexType>
 
  <complexType name="localElement" base="element" derivedBy="restriction">
   <element ref="annotation" minOccurs="0"/>
   <choice minOccurs="0">
      <element name="simpleType" type="localSimpleType"/>
      <element name="complexType" type="localComplexType"/>
   </choice>
   <element ref="identityConstraint" minOccurs="0" maxOccurs="unbounded"/>
   <attribute name="equivClass" use="prohibited"/>
   <attribute name="final" use="prohibited"/>
  </complexType>

  <element name="element" type="topLevelElement" equivClass="schemaTop"/>

  <!-- group type for named top-level groups and group references -->
  <complexType name="group" base="annotated" derivedBy="extension" abstract="true">
    <group ref="particle" minOccurs="0" maxOccurs="unbounded"/>
    <attributeGroup ref="defRef"/>
    <attributeGroup ref="occurs"/>
  </complexType>

  <complexType name="namedGroup" base="group" derivedBy="restriction">
    <element ref="annotation" minOccurs="0"/>
    <group ref="particle" minOccurs="0" maxOccurs="unbounded"/>
    <attribute name="name" use="required" type="NCName"/>
    <attribute name="ref" use="prohibited"/>
    <attribute name="minOccurs" use="prohibited"/>
    <attribute name="maxOccurs" use="prohibited"/>
  </complexType>

  <complexType name="groupRef" base="group" derivedBy="restriction">
    <element ref="annotation" minOccurs="0"/>
    <attribute name="ref" use="required" type="QName"/>
    <attribute name="name" use="prohibited"/>
  </complexType>

  <!-- group type for the three kinds of group -->
  <complexType name="explicitGroup" base="group" derivedBy="restriction">
    <element ref="annotation" minOccurs="0"/>
    <group ref="nestedParticle" minOccurs="0" maxOccurs="unbounded"/>
    <attribute name="name" type="NCName" use="prohibited"/>
    <attribute name="ref" type="QName" use="prohibited"/>
  </complexType>

  <!-- there's a bug here - - all/choice/sequence inside group
       must have no min/max -->
  <element name="all" type="explicitGroup"/>
  <element name="choice" type="explicitGroup"/>
  <element name="sequence" type="explicitGroup"/>

  <element name="group" equivClass="schemaTop" type="namedGroup"/>

  <!-- The wildcard specifier in content models -->

  <complexType name="wildcard" base="annotated" derivedBy="extension">
    <attribute name="namespace" type="namespaceList" use="default" value="##any"/>
    <attribute name="processContents" use="default" value="strict">
     <simpleType base="NMTOKEN">
      <enumeration value="skip"/>
      <enumeration value="lax"/>
      <enumeration value="strict"/>
     </simpleType>
    </attribute>
  </complexType>

  <element name="any">
   <complexType base="wildcard" derivedBy="extension">
    <attributeGroup ref="occurs"/>
   </complexType>
  </element>

  <!-- simple type for the value of the 'namespace' attr of 'any' and
       'anyAttribute' -->
  <!-- Value is
                  ##any      - - any non-conflicting WFXML/attribute at all

                  ##other    - - any non-conflicting WFXML/attribute from
                                  namespace other than targetNS

                  ##local    - - any unqualified non-conflicting WFXML/attribute 

                  one or     - - any non-conflicting WFXML/attribute from
                  more URI        the listed namespaces
                  references
                  (space separated)

                ##targetNamespace or ##local may appear in the above list, to
                    refer to the targetNamespace of the enclosing
                    schema or an absent targetNamespace respectively -->

  <simpleType name="namespaceList" base="string">
   <annotation>
    <documentation>##any | ##other | list of {uri, ##targetNamespace, ##local}</documentation>
   <documentation>A utility type, not for public use</documentation>
   </annotation>
  </simpleType>

  <!-- the attribute element declares attributes -->

  <element name="attribute" equivClass="schemaTop" type="topLevelAttribute"/>

  <!-- attributeGroup element -->

  <complexType name="attributeGroup" base="annotated" derivedBy="extension" abstract="true">
     <choice minOccurs="0" maxOccurs="unbounded">
      <element name="attribute" type="attribute"/>
      <element name="attributeGroup" type="attributeGroupRef"/>
     </choice>
     <element ref="anyAttribute" minOccurs="0"/>
     <attributeGroup ref="defRef"/>
    </complexType>
 
  <complexType name="namedAttributeGroup" base="attributeGroup" derivedBy="restriction">
    <element ref="annotation" minOccurs="0"/>
    <choice minOccurs="0" maxOccurs="unbounded">
      <element name="attribute" type="attribute"/>
      <element name="attributeGroup" type="attributeGroupRef"/>
    </choice>
    <element ref="anyAttribute" minOccurs="0"/>
    <attribute name="name" use="required" type="NCName"/>
    <attribute name="ref" use="prohibited"/>
  </complexType>

  <complexType name="attributeGroupRef" base="attributeGroup" derivedBy="restriction">
    <element ref="annotation" minOccurs="0"/>
    <attribute name="ref" use="required" type="QName"/>
    <attribute name="name" use="prohibited"/>
  </complexType>

 <element name="attributeGroup" type="namedAttributeGroup" equivClass="schemaTop"/>

 <element name="include">
  <complexType base="annotated" derivedBy="extension">
   <attribute name="schemaLocation" type="uriReference" use="required"/>
  </complexType>
 </element>

 <element name="import">
  <complexType base="annotated" derivedBy="extension">
   <attribute name="namespace" type="uriReference"/>
   <attribute name="schemaLocation" type="uriReference"/>
  </complexType>
 </element>
 
 <!-- Better reference mechanisms -->

 <simpleType name="XPathExprApprox" base="string">
  <annotation>
   <documentation>An XPath expression</documentation>
   <documentation>A utility type, not for public use</documentation>
  </annotation>
  <pattern value="(/|//|\.|\.\.|:|::|\||(\c-[.:/|])+)+">
   <annotation>
    <documentation>A VERY permissive definition,
                   probably not even right
    </documentation>
   </annotation>
  </pattern>
 </simpleType>
 
 <element name="selector" type="XPathExprApprox"/>
 <element name="field" type="XPathExprApprox"/>

 <complexType name="keybase" base="annotated" derivedBy="extension">
  <sequence>
   <element ref="selector"/>
   <element ref="field" minOccurs="1" maxOccurs="unbounded"/>
  </sequence>
  <attribute name="name" type="NCName" use="required"/>
 </complexType>

 <element name="identityConstraint" type="keybase" abstract="true"/>

 <element name="unique" equivClass="identityConstraint"/>
 <element name="key" equivClass="identityConstraint"/>
 <element name="keyref" equivClass="identityConstraint">
  <complexType base="keybase" derivedBy="extension">
   <attribute name="refer" type="QName" use="required"/>
  </complexType>
 </element>

  <!-- notation element type -->

  <element name="notation" equivClass="schemaTop">
   <complexType base="annotated" derivedBy="extension">
    <attribute name="name" type="NCName" use="required"/>
    <attribute name="public" type="public" use="required"/>
    <attribute name="system" type="uriReference"/>
   </complexType>
  </element>

  <simpleType name="public" base="string">
   <annotation>
   <documentation>A public identifier, per ISO 8879</documentation>
   <documentation>A utility type, not for public use</documentation>
   </annotation>
  </simpleType>

  <!-- notations for use within XML Schema schemas      -->

  <notation name="XMLSchemaStructures" public="structures" system="http://www.w3.org/1999/XMLSchema.xsd"/>
  <notation name="XML" public="REC-xml-19980210" system="http://www.w3.org/TR/1998/REC-xml-19980210"/>
</schema>