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  <title>HLink</title>
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<a href="http://www.w3.org/"><img height="48" width="72" alt="W3C"
src="http://www.w3.org/Icons/w3c_home" /></a>

<h1><a id="title" name="title">HLink</a></h1>

<h2><a id="subtitle" name="subtitle">Link recognition for the XHTML Family</a></h2>

<h2><a id="date" name="date">W3C Working Group Note 16 December 2010</a></h2>
<dl>
  <dt>This version:</dt>
    <dd><a href="http://www.w3.org/TR/2010/NOTE-hlink-20101216">http://www.w3.org/TR/2010/NOTE-hlink-20101216</a></dd>
  <dt>Latest version:</dt>
    <dd><a href="http://www.w3.org/TR/hlink">http://www.w3.org/TR/hlink</a></dd>
  <dt>Previous version:</dt>
    <dd><a href="http://www.w3.org/TR/2002/WD-hlink-20020913/">http://www.w3.org/TR/2002/WD-hlink-20020913</a></dd>
  <dt>Diff-marked version:</dt>
    <dd><a href="hlink-diff.html">hlink-diff.html</a></dd>
  <dt>Editors:</dt>
    <dd><a href="mailto:steven.pemberton@cwi.nl">Steven Pemberton</a>, <a
      href="http://www.cwi.nl/">CWI</a>/W3C</dd>
    <dd><a href="mailto:mimasa@w3.org">Masayasu Ishikawa</a>, W3C</dd>
</dl>

<p>This document is also available in these non-normative formats:
<a href="hlink.ps">PostScript version</a>,
<a href="hlink.pdf"><abbr title="Portable Document Format">PDF</abbr>
version</a>,
<a href="hlink.zip">ZIP archive</a>, and
<a href="hlink.tgz">Gzip'd TAR archive</a>.</p>

<p class="copyright"><a href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a> &copy; 2002-2010 <a href="http://www.w3.org/"><acronym title="World Wide Web Consortium">W3C</acronym></a><sup>&reg;</sup> (<a href="http://www.csail.mit.edu/"><acronym title="Massachusetts Institute of Technology">MIT</acronym></a>, <a href="http://www.ercim.eu/"><acronym title="European Research Consortium for Informatics and Mathematics">ERCIM</acronym></a>, <a href="http://www.keio.ac.jp/">Keio</a>), All Rights Reserved. W3C <a href="http://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>, <a href="http://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a> and <a href="http://www.w3.org/Consortium/Legal/copyright-documents">document use</a> rules apply.</p>
<hr />
</div>

<h2><a id="abstract" name="abstract">Abstract</a></h2>

<p>The HLink module defined in this specification provides XHTML Family
Members with the ability to specify which attributes of elements represent
links, and how those links should be traversed, and extends XLink use to a
wider class of languages than those restricted to the syntactic style allowed
by XLink.</p>

<h2><a id="status" name="status">Status of This Document</a></h2>

<p><em>This section describes the status of this document at the time
of its publication. Other documents may supersede this document. A
list of current W3C publications and the latest revision of this
technical report can be found in the <a
href="http://www.w3.org/TR/">W3C technical reports index</a> at
http://www.w3.org/TR/.</em></p>

<p>This document is a Working Group Note.  The XHTML2 Working Group's
charter expired before it could complete work on this document.  It is possible
that the work will be continued by another group in the future.</p>

<p>Publication as a Working Group Note does not imply endorsement by
the W3C Membership. This is a draft document and may be updated,
replaced or obsoleted by other documents at any time. It is
inappropriate to cite this document as other than work in
progress.</p>

<p>This document has been produced by the <a href="http://www.w3.org/MarkUp/">W3C XHTML 2 Working Group</a> as part of the <a href="http://www.w3.org/MarkUp/Activity">HTML Activity</a>. The goals of
the XHTML 2 Working Group are discussed in the <a href="http://www.w3.org/2007/03/XHTML2-WG-charter">XHTML 2 Working Group charter</a>.</p>

<p>This document was produced by a group operating under the <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/">5 February 2004 W3C Patent Policy</a>. W3C maintains a <a rel="disclosure"
href="http://www.w3.org/2004/01/pp-impl/32107/status">public list of any patent disclosures</a> made in connection with the deliverables of the group; that page also includes instructions for
disclosing a patent. An individual who has actual knowledge of a patent which the individual believes contains <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/#def-essential">Essential
Claim(s)</a> must disclose the information in accordance with <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/#sec-Disclosure">section 6 of the W3C Patent Policy</a>.</p>

<p>Public discussion of HTML takes place on
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</p>


<div class="toc">
<h2><a id="contents" name="contents">Contents</a></h2>
<ul class="toc">
  <li>1. <a href="#s_intro">Introduction</a></li>
  <li>2. Definitions</li>
  <li>3. <a href="#s_hlink_module">The HLink Module</a>
    <ul>
      <li>3.1. <a href="#s_hlinks-element">The hlinks Element</a></li>
      <li>3.2. <a href="#s_hlink-element">The hlink Element</a></li>
      <li>3.3. <a href="#s_examples">Examples</a></li>
    </ul>
  </li>
  <li>4. <a href="#s_usage">Usage</a></li>
  <li>A. <a href="#a_module_definition">Module Implementations</a>
    <ul>
      <li>A.1. <a href="#a_DTD_definition">DTD Implementation</a>
        <ul>
          <li>A.1.1. <a href="#a_DTD">HLink DTD</a></li>
          <li>A.1.2 <a href="#a_DTD_qname">HLink Qname Module</a></li>
        </ul>
      </li>
      <li>A.2. <a href="#a_RELAXNG_definition">RELAX NG
      Implementation</a></li>
      <li>A.3. <a href="#a_XMLSchema_definition">XML Schema
      Implementation</a></li>
    </ul>
  </li>
  <li>B. <a href="#s_refs">References</a>
    <ul>
      <li>B.1. <a href="#s_norm-refs">Normative References</a></li>
      <li>B.2. <a href="#s_other-refs">Other References</a></li>
    </ul>
  </li>
</ul>
</div>
<!--OddPage-->

<h2><a id="s_intro">1. Introduction</a></h2>

<p><em>This section is informative.</em></p>

<p>This document defines markup that can be used to describe links in XHTML
Family members. It consists of two elements that are used to associate
properties with markup elements and attributes to describe how they behave as
links. Many of the descriptive properties are taken from XLink [<a
href="#ref_xlink">XLINK</a>], but with additions to support the behaviour of
links in XHTML.</p>

<h2 id="s_definitions">2. Definitions</h2>

<p>[TBD]</p>
<!--OddPage-->

<h2><a id="s_hlink_module">3. The HLink Module</a></h2>

<p><em>This section is normative.</em></p>

<p>This specification defines a module called HLink. The module uses the XML
Namespaces [<a href="#ref_name">NAME</a>] identifier
<code>http://www.w3.org/2002/06/hlink</code>.</p>

<p>Examples in this document that use the namespace prefix
"<code>hlink</code>" all assume an <code>xmlns</code> declaration
<code>xmlns:hlink="http://www.w3.org/2002/06/hlink"</code> somewhere suitable
in the document involved. All examples are informative.</p>

<p>The remainder of this section describes the elements and attributes in
this module, the semantics, and provides an abstract module definition as
required in [<a href="#ref_xmod">XHTMLMOD</a>].</p>

<p>The HLink Module supports the following element and attributes:</p>

<table class="moduledef" border="1"
summary="Element and Attributes for HLink Module">
  <thead>
    <tr>
      <th>Element</th>
      <th>Attributes</th>
      <th>Minimal Content Model</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>hlinks</td>
      <td>-</td>
      <td>hlink+</td>
    </tr>
    <tr>
      <td>hlink</td>
      <td>namespace* (<a
        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_URI">URI</a>),
        element (<a
        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_NAME">NAME</a>),<br
        />
        locator (<a
        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_NAME">NAME</a>),
        locatorValue (<a
        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_URI">URI</a>),<br
        />
        <!--(<a
                                        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_URI">URI</a>),-->
         effect (<a
        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_NAME">NAME</a>),
        effectValue (<a
        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_URI">URI</a>),<br
        />
        <!--("new" | "replace"* | "embed" | "submit" | "map"),-->
         actuate (<a
        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_NAME">NAME</a>), <!--("onLoad" | "onRequest"* | "onRequestSecondary"),-->
         actuateValue (<a
        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_URI">URI</a>),<br
        />
        replacement (<a
        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_NAME">NAME</a>),
        replacementValue (<a
        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_URI">URI</a>),<br
        />
        role (<a
        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_NAME">NAME</a>),
        roleValue (<a
        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_URI">URI),</a>
        <br />
        shape (<a
        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_CDATA">CDATA</a>), <!--(<a
                                        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_Shape">Shape</a>),-->
         shapeValue (TBD), <br />
        coords (<a
        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_CDATA">CDATA</a>),
        coordsValue (TBD),<!--(<a
                                        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_Coords">Coords</a>),-->
         <br />
        contentType<!--(<a
                                        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_ContentType">ContentType</a>),-->
         (ContentType), contentTypeValue (TBD), <br />
        onSuccess (<a
        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_CDATA">CDATA</a>),
        onSuccessValue (TBD),<br />
        <!--("processChildren" | "ignoreChildren"*),-->
         onFailure (<a
        href="http://www.w3.org/TR/xhtml-modularization/abstraction.html#dt_CDATA">CDATA</a>),
        onFailureValue (TBD)<!--("processChildren" | "ignoreChildren" | "warn"* | "fail")-->
      </td>
      <td>EMPTY</td>
    </tr>
  </tbody>
</table>

<p>Implementations: <a href="#a_DTD_definition">DTD</a>, <a
href="#a_RELAXNG_definition">RELAX NG</a>, <a
href="#a_XMLSchema_definition">XML Schema</a></p>

<h3><a id="s_hlinks-element" name="s_hlinks-element">3.1. The hlinks
Element</a></h3>

<p>The <code>hlinks</code> element exists only to be a root element for a
document containing only <code>hlink</code> elements; see<a
href="#s_usage">section 4 Usage</a>, and the hlink:definition attribute
defined there.</p>

<div class="issue">
<p>[[Issue: you could define inheritance in nested <code>hlink</code>
elements:</p>
<pre>&lt;hlink namespace="..."&gt;
    &lt;hlink element="a" ... /&gt;
    &lt;hlink element="b" ... /&gt;
&lt;/hlink&gt;</pre>

<p>which would make writing descriptions easier, and make an outer
<code>hlinks</code> elements unnecessary, though at the cost of slightly
complicating implementation]]</p>
</div>

<h3><a id="s_hlink-element" name="s_hlink-element">3.2. The hlink
Element</a></h3>

<p>Element <code>hlink</code> is used to identify an element and/or
attributes within a namespace, and associate properties with them to specify
how the element should be treated as a link, or how the attributes contribute
to an element that is a link. The <code>hlink</code> element has the
following attributes:</p>
<dl>
  <dt>namespace</dt>
    <dd>This required attribute specifies a namespace URI that the element
      identified in the <code>element</code> attribute belongs to, or the
      other attributes when the <code>element</code> attribute is
    omitted.</dd>
  <dt>element</dt>
    <dd>This optional attribute specifies an element in the namespace
      identified by the attribute <code>namespace</code>. The rest of the
      attributes below specify properties of this element. If this attribute
      is absent, then the attributes describe global attributes (as defined
      in [<a href="#ref_name">NAME</a>]) within the namespace instead; these
      attributes then describe the element that they are actually on in the
      markup. If this attribute has the special value "<code>*</code>" then
      the rest of the attributes describe all suitable elements in the
      namespace (as defined by a DTD or schema); for instance, if the
      <code>hlink</code> element defines an attribute <code>href</code> for
      an <code>element</code> value of <code>*</code>, then all elements that
      the DTD allows to have an attribute <code>href</code> are so
    defined.</dd>
</dl>

<p>The remaining attributes come in two variants: one variant specifies a
value that indicates how the element is to behave as a link-related element,
and the other specifies the name of an attribute on the element being defined
that supplies the value. For instance:</p>
<pre>locatorValue="http://www.w3.org/"</pre>

<p>says that the element in question is a locator for a fixed URI, namely
<code>http://www.w3.org/</code>. On the other hand:</p>
<pre>locator="href"</pre>

<p>says that the element in question has an attribute named
<code>href</code>, that contains the URI of the locator.</p>

<p>If both variants are used, then the attribute-name version takes
precedence: if the named attribute (for instance <code>locator</code>) has a
value, that value is used, otherwise the value attribute is used (in this
case <code>locatorValue</code>).</p>

<p>As a shorthand, whenever this specification refers to a <em>property</em>,
it means the final value via the combination of such a pair. For instance "if
the <code>effect</code> property has the value <code>replace</code>" means
"if the <code>effect</code> attribute refers to an attribute that has the
value <code>replace</code> or the <code>effectValue</code> attribute has the
value <code>replace</code>".</p>

<p>The properties are:</p>
<dl>
  <dt>locator</dt>
    <dd>This property specifies a URI-reference [anyURI] for the link. There
      is no default value.<br />
      <span class="issue">[[Issue: URI lists, like html:archive]]</span></dd>
  <dt>effect</dt>
    <dd>This property specifies the effect of actuating the link. It has the
      following possible values:
      <dl>
        <dt>new</dt>
          <dd>The resource identified by the <code>locator</code> property is
            loaded in a new context. For instance in a windowing environment,
            the resource is loaded in a new window.</dd>
        <dt>replace</dt>
          <dd>A suitable context, as identified by the
            <code>replacement</code> property, is located, and the resource
            in that context is replaced by the resource identified by the
            <code>locator</code> property. If no such resource can be
            located, a new context with that name is created, initialised
            with the identified resource. If there is no
            <code>replacement</code> property then the initiating resource is
            replaced by the resource identified by the <code>locator</code>
            property.</dd>
        <dt>embed</dt>
          <dd>The resource identified by the <code>locator</code> property is
            considered to be embedded in the environment of the initiating
            resource. This includes images and other media resources, as well
            as such resources as scripts and style sheets.
            <p><span class="issue">[[Issue: define embed more
            precisely]]</span></p>
          </dd>
        <dt>submit</dt>
          <dd>The locator is used to submit a form.
            <p><span class="issue">[[More needs to be described here]]<br />
            [[Issue: is form submission linking?]]</span></p>
          </dd>
        <dt>map</dt>
          <dd>The resource identified by the <code>locator</code> property
            describes how the presentation of the current element is to be
            interpreted as a series of links to further resources.
            <p><span class="issue">[[More/better: this is here as a
            placeholder to describe XHTML's image maps]]</span></p>
          </dd>
      </dl>
      <p>The default value is <code>replace</code>.</p>
    </dd>
  <dt>actuate</dt>
    <dd>This property specifies the manner that the link should or can be
      actuated. It has the following possible values:
      <dl>
        <dt>onLoad</dt>
          <dd>Actuation of the link is done on loading the initiating
            resource.</dd>
        <dt>onRequest</dt>
          <dd>Actuation is done by the user using the primary actuation
            method or by a method (such as scripting) imitating this
          behavior.</dd>
        <dt>onRequestSecondary</dt>
          <dd>Actuation is done by the user using a secondary actuation
            method or by a method (such as scripting) imitating this
            behavior. For instance, an element specifying a link (such as
            XHTML's <code>a</code> element) may contain an image (for
            instance using XHTML's <code>img</code> element) that
            additionally has a link to a resource describing that image (such
            as XHTML's <code>longdesc</code> attribute). The primary
            actuation method must activate the <code>a</code> element; the
            secondary actuation method must allow the user to request
            activation of any of the other resources available at that point
            (for instance via a pop-up menu).</dd>
      </dl>
      <p>The default value is <code>onRequest</code>.</p>
    </dd>
  <dt>replacement</dt>
    <dd>This property specifies an environment in the case that the
      <code>effect</code> property has the value <code>replace</code>. If the
      <code>effect</code> property does not have that value, the
      <code>replacement</code> property is ignored.</dd>
  <dt>role</dt>
    <dd><p>This property gives information to the user agent about the role
      the link plays. <span class="issue">[[More]]</span></p>
      <p class="issue">[[These are the values that rel and rev can take
      according to HTML 4: Contents Glossary Copyright Chapter Section
      Subsection Appendix Help Bookmark Index Next Prev Alternate Start
      Stylesheet, and other specifications have added other values; e.g.
      P3P]]</p>
    </dd>
  <dt>shape</dt>
    <dd class="issue">[[for image maps: default rect circle poly]]</dd>
  <dt>coords</dt>
    <dd class="issue">[[For image maps: list of coordinates [[or
      percentages?]]]]</dd>
  <dt>contentType</dt>
    <dd>This property specifies the allowable content types of the relevant
      resource. At its most general, it is a comma-separated list of media
      ranges with optional accept parameters, as defined in section 14.1 of
      [<a class="nref"
      href="http://www.w3.org/TR/2003/WD-xhtml2-20030131/references.html#ref_RFC2616">RFC2616</a>]
      as the field value of the accept request header.
      <p>In its simplest case, this is just a media type, such as "image/png"
      or "application/xml", but it may also contain asterisks, such as
      "image/*" or "*/*", or lists of acceptable media types, such as
      "image/png, image/gif, image/jpeg".</p>
      <p>The user agent must combine this list it with its own list of
      acceptable media types by taking the intersection, and then use the
      resulting list as the field value of the <code>accept</code> request
      header when requesting the resource using HTTP.</p>
      <p>For instance, if the property specifies the value "image/png,
      image/gif, image/jpeg", but the user agent does not accept images of
      type "image/gif" then the resultant accept header would contain
      "image/png, image/jpeg".</p>
      <p>A user agent should imitate similar behavior when using other
      methods than HTTP. For instance, when accessing files in a local
      filestore, a <code>contentType</code> property of <code>"image/png,
      image/jpeg"</code> might cause the user agent first to look for a file
      with extension <code>.png</code>, and then for one with extension
      <code>.jpg</code>.</p>
      <p>If this property is not present, "*/*" is used for its value.</p>
    </dd>
  <dt>onSuccess</dt>
    <dd>This property indicates the required processing after successfully
      actuating a link that has an <code>effect</code> property of
      <code>embed</code> and an <code>actuate</code> property of
      <code>onLoad</code>. It has two values:
      <dl>
        <dt>processChildren</dt>
          <dd>processing should continue by processing the children of the
            element</dd>
        <dt>ignoreChildren</dt>
          <dd>processing should continue by ignoring the children of the
            element</dd>
      </dl>
      <p>(If the element has no children, these two values are equivalent)</p>
      <p>The default value is <code>ignoreChildren</code>.</p>
    </dd>
  <dt>onFailure</dt>
    <dd>This property indicates the required processing when a link that has
      an <code>effect</code> property of <code>embed</code> and an
      <code>actuate</code> property of <code>onLoad</code> cannot be
      actuated, either because of network failure or the resource not being
      available or found, or because the user agent cannot process the
      resource or the <code>contentType</code> property indicates that the user
      agent would not be able to process the resource. It has four possible
      values:
      <dl>
        <dt>processChildren</dt>
          <dd>processing should continue by processing the children of the
            element</dd>
        <dt>ignoreChildren</dt>
          <dd>processing should continue by ignoring the children of the
            element</dd>
        <dt>warn</dt>
          <dd>processing continues, though it must be made obvious to the
            user that the actuation failed</dd>
        <dt>fail</dt>
          <dd>processing stops with an error message</dd>
      </dl>
      <p>The default value is <code>warn</code>.</p>
    </dd>
</dl>

<p class="issue">[[Issue: onSuccess and onFailure need more work to cover
other onLoad cases]]</p>

<p><span class="issue">[[Issue: replace onSuccess/onFailure with
fallback="..."?]]</span></p>

<p class="issue">[[Issue: markup for case where link has a side-effect
needed?]]</p>

<h2><a id="s_examples" name="s_examples">3.3. Examples</a></h2>
<ol>
  <li>The definition of the <code>&lt;a href="..."&gt;</code> element in
    XHTML:
    <pre>&lt;hlink namespace="http://www.w3.org/1999/xhtml"
       element="a"
       locator="href"
       effectValue="replace"
       actuateValue="onRequest"
       replacement="target"/&gt;</pre>
  </li>
  <li>Defining <code>&lt;img/&gt;</code> in XHTML
    <pre>&lt;hlink namespace="http://www.w3.org/1999/xhtml"
       element="img"
       locator="src"
       effectValue="embed"
       actuateValue="onLoad"
       onFailureValue="warn"/&gt;
&lt;hlink namespace="http://www.w3.org/1999/xhtml"
       element="img"
       locator="longdesc"
       effectValue="new"
       actuateValue="onRequestSecondary"/&gt;
&lt;hlink namespace="http://www.w3.org/1999/xhtml"
       element="img"
       locator="usemap"
       effectValue="map"
       actuateValue="onLoad"/&gt;</pre>
  </li>
  <li>Defining <code>&lt;object&gt;</code> in XHTML
    <pre>&lt;hlink namespace="http://www.w3.org/1999/xhtml"
       element="object"
       locator="data"
       effectValue="embed"
       actuateValue="onLoad"
       onFailureValue="processChildren"
       onSuccessValue="ignoreChildren"/&gt;</pre>
  </li>
  <li>Defining a new <code>&lt;home/&gt;</code> element
    <pre>&lt;hlink namespace="http://www.example.com/markup"
       element="home"
       locatorValue="/"
       effectValue="replace"
       actuateValue="onRequest"/&gt;
&lt;hlink namespace="http://www.example.com/markup"
       element="home"
       locatorValue="/icons/home.png"
       effectValue="embed"
       actuateValue="onLoad"/&gt;</pre>
    <p>In the context of this definition, and the namespace declaration</p>
    <pre>xmlns="http://www.example.com/markup"</pre>
    <p>the markup</p>
    <pre>&lt;home/&gt;</pre>
    <p>will display a clickable icon that takes the user to the home page.</p>
  </li>
  <li>Defining redirection:
    <pre>&lt;hlink namespace="http://www.example.com/markup"
       element="redirect"
       locator="href"
       effectValue="replace"
       actuateValue="onLoad"/&gt;</pre>
    <p>In the context of this definition and a suitable namespace
    declaration, the following markup will cause the initiating resource to
    be redirected:</p>
    <pre>&lt;redirect href="whereever"&gt;This page has moved&lt;/redirect&gt;</pre>
  </li>
  <li>Defining <code>&lt;html:blockquote&gt;</code>
    <pre>&lt;hlink namespace="http://www.w3.org/1999/xhtml"
       element="blockquote"
       locator="cite"
       effectValue="new"
       actuateValue="onRequestSecondary"/&gt;</pre>
  </li>
  <li>Defining RDF
    <pre>&lt;hlink namespace="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
       element="Description"
       locator="about"
       effectValue="new"
       actuateValue="onRequestSecondary"/&gt;
&lt;hlink namespace="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
       locator="resource"
       effectValue="new"
       actuateValue="onRequestSecondary"/&gt;</pre>
  </li>
</ol>

<h2><a id="s_usage" name="s_usage">4. Usage</a></h2>

<p><em>This section is normative.</em></p>

<p>There are two ways to use HLink. The first is <span class="issue">[[by
putting the <code>&lt;hlink&gt;s</code> in the <code>&lt;head&gt;</code>, and
the other by putting them in a separate resource, and referring to that
resource by a <code>hlink:definition</code> URI attribute on the root element
of the document</span></p>

<div class="issue">
<p>Either this</p>
<pre>&lt;html hlink:definition="http://www.example.org/whatever" ...&gt;</pre>

<p>or this:</p>
<pre>&lt;html ...&gt;
&lt;head&gt;
    &lt;hlink:hlink ... /&gt;
    ...
&lt;/head&gt;</pre>

<p>]]</p>
</div>
<!--OddPage-->

<h2><a id="a_module_definition" name="a_module_definition">A. Module
Implementations</a></h2>

<p>This appendix is <em>normative</em>.</p>

<p>[[NOT YET UP TO DATE]]</p>

<h3><a id="a_DTD_definition" name="a_DTD_definition">A.1. DTD
Implementation</a></h3>

<h3><a id="a_DTD" name="a_DTD">A.1.1. HLink DTD</a></h3>
<pre class="dtd">&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;!-- ...................................................................... --&gt;
&lt;!-- HLink DTD ............................................................ --&gt;
&lt;!-- URI: http://www.w3.org/2002/06/hlink.dtd

     This is HLink - a link recongnition mechanism for the XHTML Family.

     Copyright &copy;2002 W3C (MIT, INRIA, Keio), All Rights Reserved.

       Editor:   Masayasu Ishikawa &lt;mimasa@w3.org&gt;
       Revision: $Id: Overview.html,v 1.3 2010/12/16 20:58:10 plehegar Exp $

     Permission to use, copy, modify and distribute the HLink DTD and its
     accompanying documentation for any purpose and without fee is hereby
     granted in perpetuity, provided that the above copyright notice and
     this paragraph appear in all copies.  The copyright holders make no
     representation about the suitability of this DTD for any purpose.

     It is provided "as is" without expressed or implied warranty.

     This DTD module is identified by the PUBLIC and SYSTEM identifiers:

       PUBLIC "-//W3C//DTD HLink 1.0//EN"
       SYSTEM "http://www.w3.org/2002/06/hlink.dtd"

     Revisions:
     (none)
     ....................................................................... --&gt;

&lt;!-- HLink

     hlinks, hlink

     This HLink DTD declares elements and attributes defining
     HLink, a link recongnition mechanism for the XHTML Family.
--&gt;

&lt;!-- Datatypes

     defines containers for the following datatypes, many of
     these imported from other specifications and standards -
     not quite used at the moment.
--&gt;

&lt;!-- media type, as per [RFC2045] --&gt;
&lt;!ENTITY % ContentType.datatype "CDATA" &gt;

&lt;!-- comma separated list of coordinates to use in defining areas --&gt;
&lt;!ENTITY % Coords.datatype "CDATA" &gt;

&lt;!-- space-separated list of link types --&gt;
&lt;!ENTITY % LinkTypes.datatype "NMTOKENS" &gt;

&lt;!-- the shape of a region --&gt;
&lt;!ENTITY % Shape.datatype "( default | rect | circle | poly )"&gt;

&lt;!-- a Uniform Resource Identifier reference, as per anyURI in
     XML Schema Part 2 [SCHEMA]
--&gt;
&lt;!ENTITY % URI.datatype "CDATA" &gt;

&lt;!-- HLink Qname (Qualified Name) Module --&gt;
&lt;!ENTITY % hlink-qname.mod
    PUBLIC "-//W3C//ENTITIES HLink Qualified Names 1.0//EN"
           "hlink-qname.mod" &gt;
%hlink-qname.mod;

&lt;!-- hlinks element .................................... --&gt;
&lt;!ELEMENT %HLINK.hlinks.qname; ( %HLINK.hlink.qname; )+ &gt;
&lt;!ATTLIST %HLINK.hlinks.qname;
    %HLINK.xmlns.attrib;
&gt;

&lt;!-- hlink element ..................................... --&gt;
&lt;!ELEMENT %HLINK.hlink.qname; EMPTY &gt;
&lt;!ATTLIST %HLINK.hlink.qname;
    %HLINK.xmlns.attrib;
    namespace   %URI.datatype; #REQUIRED
    element     NMTOKEN        #IMPLIED
    locator     CDATA          #IMPLIED
    effect      CDATA          #IMPLIED
    actuate     CDATA          #IMPLIED
    replacement CDATA          #IMPLIED
    role        CDATA          #IMPLIED
    reverseRole CDATA          #IMPLIED
    shape       CDATA          #IMPLIED
    coords      CDATA          #IMPLIED
    arcrole     CDATA          #IMPLIED
    label       CDATA          #IMPLIED
    from        CDATA          #IMPLIED
    to          CDATA          #IMPLIED
    contentType   CDATA          #IMPLIED
    onSuccess   CDATA          #IMPLIED
    onFailure   CDATA          #IMPLIED
&gt;

&lt;!-- end of hlink.dtd --&gt;</pre>

<h3><a id="a_DTD_qname" name="a_DTD_qname">A.1.2. HLink Qname Module</a></h3>
<pre class="dtd">&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;!-- ....................................................................... --&gt;
&lt;!-- HLink Qname Module  ................................................... --&gt;
&lt;!-- URI: http://www.w3.org/2002/06/hlink-qname.mod

     This is HLink - a link recongnition mechanism for the XHTML Family.

     Copyright &copy;2002 W3C (MIT, INRIA, Keio), All Rights Reserved.

     Revision: $Id: Overview.html,v 1.3 2010/12/16 20:58:10 plehegar Exp $

     This DTD module is identified by the PUBLIC and SYSTEM identifiers:

       PUBLIC "-//W3C//ENTITIES HLink Qualified Names 1.0//EN"
       SYSTEM "http://www.w3.org/2002/06/hlink-qname.mod"

     Revisions:
     (none)
     ....................................................................... --&gt;

&lt;!-- HLink Qname (Qualified Name) Module

     This module is contained in two parts, labeled Section 'A' and 'B':

       Section A declares parameter entities to support namespace-
       qualified names, namespace declarations, and name prefixing
       for HLink and extensions.

       Section B declares parameter entities used to provide
       namespace-qualified names for all HLink element types:

         %HLINK.hlinks.qname;   the xmlns-qualified name for &lt;hlinks&gt;
         ...
--&gt;

&lt;!-- Section A: HLink XML Namespace Framework :::::::::::::::::::: --&gt;

&lt;!-- 1. Declare a %HLINK.prefixed; conditional section keyword, used
        to activate namespace prefixing. The default value should
        inherit '%HLINK.NS.prefixed;' from the DTD driver, so that unless
        overridden, the default behaviour follows the overall DTD
        prefixing scheme.
--&gt;
&lt;!ENTITY % HLINK.NS.prefixed "IGNORE" &gt;
&lt;!ENTITY % HLINK.prefixed "%HLINK.NS.prefixed;" &gt;

&lt;!-- 2. Declare a parameter entity (eg., %HLINK.xmlns;) containing
        the URI reference used to identify the HLink namespace
--&gt;
&lt;!ENTITY % HLINK.xmlns  "http://www.w3.org/2002/06/hlink" &gt;

&lt;!-- 3. Declare parameter entities (eg., %MODULE.prefix;) containing
        the default namespace prefix string(s) to use when prefixing
        is enabled. This may be overridden in the DTD driver or the
        internal subset of an document instance. If no default prefix
        is desired, this may be declared as an empty string.

     NOTE: As specified in [XMLNAMES], the namespace prefix serves
     as a proxy for the URI reference, and is not in itself significant.
--&gt;
&lt;!ENTITY % HLINK.prefix  "hlink" &gt;

&lt;!-- 4. Declare parameter entities (eg., %HLINK.pfx;) containing the
        colonized prefix(es) (eg., '%HLINK.prefix;:') used when
        prefixing is active, an empty string when it is not.
--&gt;
&lt;![%HLINK.prefixed;[
&lt;!ENTITY % HLINK.pfx  "%HLINK.prefix;:" &gt;
]]&gt;
&lt;!ENTITY % HLINK.pfx  "" &gt;

&lt;!-- declare qualified name extensions here ............ --&gt;
&lt;!ENTITY % hlink-qname-extra.mod "" &gt;
%hlink-qname-extra.mod;

&lt;!-- 5. The parameter entity %HLINK.xmlns.extra.attrib; may be
        redeclared to contain any non-HLink namespace declaration
        attributes for namespaces embedded in XML. The default
        is an empty string.  XLink should be included here if used
        in the DTD.
--&gt;
&lt;!ENTITY % HLINK.xmlns.extra.attrib "" &gt;

&lt;![%HLINK.prefixed;[
&lt;!ENTITY % HLINK.NS.decl.attrib
     "xmlns:%HLINK.prefix;  %URI.datatype;  #FIXED '%HLINK.xmlns;'
      %HLINK.xmlns.extra.attrib;"
&gt;
]]&gt;
&lt;!ENTITY % HLINK.NS.decl.attrib
     "%HLINK.xmlns.extra.attrib;"
&gt;

&lt;!-- Declare a parameter entity %HLINK.NS.decl.attrib; containing all
     XML namespace declaration attributes used by HLink, including
     a default xmlns declaration when prefixing is inactive.
--&gt;
&lt;![%HLINK.prefixed;[
&lt;!ENTITY % HLINK.xmlns.attrib
     "%HLINK.NS.decl.attrib;"
&gt;
]]&gt;
&lt;!ENTITY % HLINK.xmlns.attrib
     "xmlns                   %URI.datatype;  #FIXED '%HLINK.xmlns;'
      %HLINK.xmlns.extra.attrib;"
&gt;

&lt;!-- Section B: XML Qualified Names ::::::::::::::::::::::::::::: --&gt;

&lt;!-- 6. This section declares parameter entities used to provide
        namespace-qualified names for all HLink element types.
--&gt;

&lt;!ENTITY % HLINK.hlinks.qname "%HLINK.pfx;hlinks" &gt;
&lt;!ENTITY % HLINK.hlink.qname "%HLINK.pfx;hlink" &gt;

&lt;!-- end of hlink-qname.mod --&gt;</pre>

<h3><a id="a_RELAXNG_definition" name="a_RELAXNG_definition">A.2. RELAX NG
Implementation</a></h3>
<pre class="rng">&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;grammar xmlns="http://relaxng.org/ns/structure/1.0"
         xmlns:a="http://relaxng.org/ns/compatibility/annotations/1.0"
         ns="http://www.w3.org/2002/06/hlink"
         datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes"&gt;

  &lt;start&gt;
    &lt;choice&gt;
      &lt;ref name="hlinks"/&gt;
    &lt;/choice&gt;
  &lt;/start&gt;

  &lt;a:documentation&gt;
     HLink in RELAX NG
     URI: http://www.w3.org/2002/06/hlink.rng

     This is HLink - a link recongnition mechanism for the XHTML Family.

     Copyright &copy;2002 W3C (MIT, INRIA, Keio), All Rights Reserved.

       Editor:   Masayasu Ishikawa (mimasa@w3.org)
       Revision: $Id: Overview.html,v 1.3 2010/12/16 20:58:10 plehegar Exp $

     Permission to use, copy, modify and distribute the HLink RELAX NG
     schema and its accompanying documentation for any purpose and
     without fee is hereby  granted in perpetuity, provided that
     the above copyright notice and this paragraph appear in all copies.
     The copyright holders make no  representation about the suitability
     of this RELAX NG schema for any purpose.

     It is provided "as is" without expressed or implied warranty.

     Revisions:
     (none)
  &lt;/a:documentation&gt;

  &lt;a:documentation&gt;
     HLink

     hlinks, hlink

     This HLink RELAX NG schema declares elements and attributes defining
     HLink, a link recongnition mechanism for the XHTML Family.
  &lt;/a:documentation&gt;

  &lt;a:documentation&gt;
     Datatypes

     defines containers for the following datatypes, many of
     these imported from other specifications and standards.
  &lt;/a:documentation&gt;

  &lt;define name="AttName"&gt;
    &lt;a:documentation&gt;
       the name of an attribute which begins with "@", a la @name
    &lt;/a:documentation&gt;
    &lt;data type="string"&gt;
      &lt;param name="pattern"&gt;@\c+&lt;/param&gt;
    &lt;/data&gt;
  &lt;/define&gt;

  &lt;define name="ContentType"&gt;
    &lt;a:documentation&gt;
       media type, as per [RFC2045]
    &lt;/a:documentation&gt;
    &lt;text/&gt;
  &lt;/define&gt;

  &lt;define name="Coords"&gt;
    &lt;a:documentation&gt;
       comma separated list of coordinates to use in defining areas
    &lt;/a:documentation&gt;
    &lt;data type="string"&gt;
      &lt;param name="pattern"
        &gt;[-+]?(\d+|\d+(\.\d+)?%)(,\s*[-+]?(\d+|\d+(\.\d+)?%))*&lt;/param&gt;
    &lt;/data&gt;
  &lt;/define&gt;

  &lt;define name="LinkTypes"&gt;
    &lt;a:documentation&gt;
       space-separated list of link types
    &lt;/a:documentation&gt;
    &lt;data type="NMTOKENS"/&gt;
  &lt;/define&gt;

  &lt;define name="Shape"&gt;
    &lt;a:documentation&gt;
       the shape of a region
    &lt;/a:documentation&gt;
    &lt;choice&gt;
      &lt;value&gt;default&lt;/value&gt;
      &lt;value&gt;rect&lt;/value&gt;
      &lt;value&gt;circle&lt;/value&gt;
      &lt;value&gt;poly&lt;/value&gt;
    &lt;/choice&gt;
  &lt;/define&gt;

  &lt;define name="URI"&gt;
    &lt;a:documentation&gt;
       a Uniform Resource Identifier reference, as per anyURI in
       XML Schema Part 2 [SCHEMA]
    &lt;/a:documentation&gt;
    &lt;data type="anyURI"/&gt;
  &lt;/define&gt;

  &lt;define name="hlinks"&gt;
    &lt;a:documentation&gt;
       hlinks element
    &lt;/a:documentation&gt;
    &lt;element name="hlinks"&gt;
      &lt;oneOrMore&gt;
        &lt;ref name="hlink"/&gt;
      &lt;/oneOrMore&gt;
    &lt;/element&gt;
  &lt;/define&gt;

  &lt;define name="hlink"&gt;
    &lt;a:documentation&gt;
       hlink element
    &lt;/a:documentation&gt;
    &lt;element name="hlink"&gt;
      &lt;ref name="hlink.attlist"/&gt;
    &lt;/element&gt;
  &lt;/define&gt;

  &lt;define name="hlink.attlist"&gt;
    &lt;attribute name="namespace"&gt;
      &lt;ref name="URI"/&gt;
    &lt;/attribute&gt;
    &lt;optional&gt;
      &lt;attribute name="element"&gt;
        &lt;data type="NMTOKEN"/&gt;
      &lt;/attribute&gt;
    &lt;/optional&gt;
    &lt;optional&gt;
      &lt;attribute name="locator"&gt;
        &lt;choice&gt;
          &lt;ref name="URI"/&gt;
          &lt;ref name="AttName"/&gt;
        &lt;/choice&gt;
      &lt;/attribute&gt;
    &lt;/optional&gt;
    &lt;optional&gt;
      &lt;attribute name="effect" a:defaultValue="replace"&gt;
        &lt;choice&gt;
          &lt;value&gt;new&lt;/value&gt;
          &lt;value&gt;replace&lt;/value&gt;
          &lt;value&gt;embed&lt;/value&gt;
          &lt;value&gt;submit&lt;/value&gt;
          &lt;value&gt;map&lt;/value&gt;
          &lt;ref name="AttName"/&gt;
        &lt;/choice&gt;
      &lt;/attribute&gt;
    &lt;/optional&gt;
    &lt;optional&gt;
      &lt;attribute name="actuate" a:defaultValue="onRequest"&gt;
        &lt;choice&gt;
          &lt;value&gt;onLoad&lt;/value&gt;
          &lt;value&gt;onRequest&lt;/value&gt;
          &lt;value&gt;onRequestSecondary&lt;/value&gt;
          &lt;ref name="AttName"/&gt;
        &lt;/choice&gt;
      &lt;/attribute&gt;
    &lt;/optional&gt;
    &lt;optional&gt;
      &lt;attribute name="replacement"/&gt;
    &lt;/optional&gt;
    &lt;optional&gt;
      &lt;attribute name="role"&gt;
        &lt;choice&gt;
          &lt;ref name="LinkTypes"/&gt;
          &lt;ref name="AttName"/&gt;
        &lt;/choice&gt;
      &lt;/attribute&gt;
    &lt;/optional&gt;
    &lt;optional&gt;
      &lt;attribute name="reverseRole"&gt;
        &lt;choice&gt;
          &lt;ref name="LinkTypes"/&gt;
          &lt;ref name="AttName"/&gt;
        &lt;/choice&gt;
       &lt;/attribute&gt;
    &lt;/optional&gt;
    &lt;optional&gt;
      &lt;attribute name="shape" a:defaultValue="default"&gt;
        &lt;choice&gt;
          &lt;ref name="Shape"/&gt;
          &lt;ref name="AttName"/&gt;
        &lt;/choice&gt;
      &lt;/attribute&gt;
    &lt;/optional&gt;
    &lt;optional&gt;
      &lt;attribute name="coords"&gt;
        &lt;choice&gt;
          &lt;ref name="Shape"/&gt;
          &lt;ref name="AttName"/&gt;
        &lt;/choice&gt;
      &lt;/attribute&gt;
    &lt;/optional&gt;
    &lt;optional&gt;
      &lt;attribute name="arcrole"&gt;
        &lt;choice&gt;
          &lt;ref name="URI"/&gt;
          &lt;ref name="AttName"/&gt;
        &lt;/choice&gt;
      &lt;/attribute&gt;
    &lt;/optional&gt;
    &lt;optional&gt;
      &lt;attribute name="label"/&gt;
    &lt;/optional&gt;
    &lt;optional&gt;
      &lt;attribute name="from"/&gt;
    &lt;/optional&gt;
    &lt;optional&gt;
      &lt;attribute name="to"/&gt;
    &lt;/optional&gt;
    &lt;optional&gt;
      &lt;attribute name="contentType"&gt;
        &lt;choice&gt;
          &lt;ref name="ContentType"/&gt;
          &lt;ref name="AttName"/&gt;
        &lt;/choice&gt;
      &lt;/attribute&gt;
    &lt;/optional&gt;
    &lt;optional&gt;
      &lt;attribute name="onSuccess" a:defaultValue="ignoreChildren"&gt;
        &lt;choice&gt;
          &lt;value&gt;processChildren&lt;/value&gt;
          &lt;value&gt;ignoreChildren&lt;/value&gt;
          &lt;ref name="AttName"/&gt;
        &lt;/choice&gt;
      &lt;/attribute&gt;
    &lt;/optional&gt;
    &lt;optional&gt;
      &lt;attribute name="onFailure" a:defaultValue="warn"&gt;
        &lt;choice&gt;
          &lt;value&gt;processChildren&lt;/value&gt;
          &lt;value&gt;ignoreChildren&lt;/value&gt;
          &lt;value&gt;warn&lt;/value&gt;
          &lt;value&gt;fail&lt;/value&gt;
          &lt;ref name="AttName"/&gt;
        &lt;/choice&gt;
      &lt;/attribute&gt;
    &lt;/optional&gt;
  &lt;/define&gt;

&lt;/grammar&gt;</pre>

<h3><a id="a_XMLSchema_definition" name="a_XMLSchema_definition">A.3. XML
Schema Implementation</a></h3>
<pre class="xsd">&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           targetNamespace="http://www.w3.org/2002/06/hlink"
           xmlns="http://www.w3.org/2002/06/hlink"
           elementFormDefault="qualified"&gt;

  &lt;xs:annotation&gt;
    &lt;xs:documentation&gt;
    HLink in XML Schema
    URI: http://www.w3.org/2002/06/hlink.xsd

    This is HLink - a link recongnition mechanism for the XHTML Family.

    Copyright &copy;2002 W3C (MIT, INRIA, Keio), All Rights Reserved.

      Editor:   Masayasu Ishikawa (mimasa@w3.org)
      Revision: $Id: Overview.html,v 1.3 2010/12/16 20:58:10 plehegar Exp $

    Permission to use, copy, modify and distribute the HLink XML Schema
    and its accompanying documentation for any purpose and without fee
    is hereby granted in perpetuity, provided that the above copyright
    notice and this paragraph appear in all copies.
    The copyright holders make no  representation about the suitability
    of this XML Schema for any purpose.

    It is provided "as is" without expressed or implied warranty.

    Revisions:
    (none)
    &lt;/xs:documentation&gt;
  &lt;/xs:annotation&gt;

  &lt;xs:annotation&gt;
    &lt;xs:documentation&gt;
    HLink

    hlinks, hlink

    This HLink XML Schema declares elements and attributes defining
    HLink, a link recongnition mechanism for the XHTML Family.
    &lt;/xs:documentation&gt;
  &lt;/xs:annotation&gt;

  &lt;xs:annotation&gt;
    &lt;xs:documentation&gt;
    Datatypes

    defines containers for the following datatypes, many of
    these imported from other specifications and standards.
    &lt;/xs:documentation&gt;
  &lt;/xs:annotation&gt;

  &lt;xs:simpleType name="AttName"&gt;
    &lt;xs:annotation&gt;
      &lt;xs:documentation&gt;
      the name of an attribute which begins with "@", a la @name
      &lt;/xs:documentation&gt;
    &lt;/xs:annotation&gt;
    &lt;xs:restriction base="xs:string"&gt;
      &lt;xs:pattern value="@\c+"/&gt;
    &lt;/xs:restriction&gt;
  &lt;/xs:simpleType&gt;

  &lt;xs:simpleType name="ContentType"&gt;
    &lt;xs:annotation&gt;
      &lt;xs:documentation&gt;
      media type, as per [RFC2045]
      &lt;/xs:documentation&gt;
    &lt;/xs:annotation&gt;
    &lt;xs:restriction base="xs:string"/&gt;
  &lt;/xs:simpleType&gt;

  &lt;xs:simpleType name="Coords"&gt;
    &lt;xs:annotation&gt;
      &lt;xs:documentation&gt;
      comma separated list of lengths
      &lt;/xs:documentation&gt;
    &lt;/xs:annotation&gt;
    &lt;xs:restriction base="xs:string"&gt;
      &lt;xs:pattern
          value="[-+]?(\d+|\d+(\.\d+)?%)(,\s*[-+]?(\d+|\d+(\.\d+)?%))*"/&gt;
    &lt;/xs:restriction&gt;
  &lt;/xs:simpleType&gt;

  &lt;xs:simpleType name="LinkTypes"&gt;
    &lt;xs:annotation&gt;
      &lt;xs:documentation&gt;
      space-separated list of link types
      &lt;/xs:documentation&gt;
    &lt;/xs:annotation&gt;
    &lt;xs:restriction base="xs:NMTOKENS"/&gt;
  &lt;/xs:simpleType&gt;

  &lt;xs:simpleType name="Shape"&gt;
    &lt;xs:restriction base="xs:token"&gt;
      &lt;xs:enumeration value="default"/&gt;
      &lt;xs:enumeration value="rect"/&gt;
      &lt;xs:enumeration value="circle"/&gt;
      &lt;xs:enumeration value="poly"/&gt;
    &lt;/xs:restriction&gt;
  &lt;/xs:simpleType&gt;

  &lt;xs:simpleType name="URI"&gt;
    &lt;xs:annotation&gt;
      &lt;xs:documentation&gt;
      a Uniform Resource Identifier reference, as per anyURI in
      XML Schema Part 2 [SCHEMA]
      &lt;/xs:documentation&gt;
    &lt;/xs:annotation&gt;
    &lt;xs:restriction base="xs:anyURI"/&gt;
  &lt;/xs:simpleType&gt;

  &lt;xs:simpleType name="Effect"&gt;
    &lt;xs:restriction base="xs:token"&gt;
      &lt;xs:enumeration value="new"/&gt;
      &lt;xs:enumeration value="replace"/&gt;
      &lt;xs:enumeration value="embed"/&gt;
      &lt;xs:enumeration value="submit"/&gt;
      &lt;xs:enumeration value="map"/&gt;
    &lt;/xs:restriction&gt;
  &lt;/xs:simpleType&gt;

  &lt;xs:simpleType name="Actuate"&gt;
    &lt;xs:restriction base="xs:token"&gt;
      &lt;xs:enumeration value="onLoad"/&gt;
      &lt;xs:enumeration value="onRequest"/&gt;
      &lt;xs:enumeration value="onRequestSecondary"/&gt;
    &lt;/xs:restriction&gt;
  &lt;/xs:simpleType&gt;

  &lt;xs:simpleType name="OnSuccess"&gt;
    &lt;xs:restriction base="xs:token"&gt;
      &lt;xs:enumeration value="processChildren"/&gt;
      &lt;xs:enumeration value="ignoreChildren"/&gt;
    &lt;/xs:restriction&gt;
  &lt;/xs:simpleType&gt;

  &lt;xs:simpleType name="OnFailure"&gt;
    &lt;xs:restriction base="xs:token"&gt;
      &lt;xs:enumeration value="processChildren"/&gt;
      &lt;xs:enumeration value="ignoreChildren"/&gt;
      &lt;xs:enumeration value="warn"/&gt;
      &lt;xs:enumeration value="fail"/&gt;
    &lt;/xs:restriction&gt;
  &lt;/xs:simpleType&gt;

  &lt;xs:element name="hlinks"&gt;
    &lt;xs:annotation&gt;
      &lt;xs:documentation&gt;
      hlinks element
      &lt;/xs:documentation&gt;
    &lt;/xs:annotation&gt;
    &lt;xs:complexType&gt;
      &lt;xs:sequence&gt;
        &lt;xs:element maxOccurs="unbounded" ref="hlink"/&gt;
      &lt;/xs:sequence&gt;
    &lt;/xs:complexType&gt;
  &lt;/xs:element&gt;

  &lt;xs:element name="hlink"&gt;
    &lt;xs:annotation&gt;
      &lt;xs:documentation&gt;
      hlink element
      &lt;/xs:documentation&gt;
    &lt;/xs:annotation&gt;
    &lt;xs:complexType&gt;
      &lt;xs:attributeGroup ref="hlink.attlist"/&gt;
    &lt;/xs:complexType&gt;
  &lt;/xs:element&gt;

  &lt;xs:attributeGroup name="hlink.attlist"&gt;
    &lt;xs:attribute name="namespace" use="required" type="URI"/&gt;
    &lt;xs:attribute name="element" type="xs:NMTOKEN"/&gt;
    &lt;xs:attribute name="locator"&gt;
      &lt;xs:simpleType&gt;
  &lt;xs:union memberTypes="URI AttName"/&gt;
      &lt;/xs:simpleType&gt;
    &lt;/xs:attribute&gt;
    &lt;xs:attribute name="effect" default="replace"&gt;
      &lt;xs:simpleType&gt;
  &lt;xs:union memberTypes="Effect AttName"/&gt;
      &lt;/xs:simpleType&gt;
    &lt;/xs:attribute&gt;
    &lt;xs:attribute name="actuate" default="onRequest"&gt;
      &lt;xs:simpleType&gt;
  &lt;xs:union memberTypes="Actuate AttName"/&gt;
      &lt;/xs:simpleType&gt;
    &lt;/xs:attribute&gt;
    &lt;xs:attribute name="replacement"/&gt;
    &lt;xs:attribute name="role"&gt;
      &lt;xs:simpleType&gt;
  &lt;xs:union memberTypes="LinkTypes AttName"/&gt;
      &lt;/xs:simpleType&gt;
    &lt;/xs:attribute&gt;
    &lt;xs:attribute name="reverseRole"&gt;
      &lt;xs:simpleType&gt;
  &lt;xs:union memberTypes="LinkTypes AttName"/&gt;
      &lt;/xs:simpleType&gt;
    &lt;/xs:attribute&gt;
    &lt;xs:attribute name="shape" default="default"&gt;
      &lt;xs:simpleType&gt;
  &lt;xs:union memberTypes="Shape AttName"/&gt;
      &lt;/xs:simpleType&gt;
    &lt;/xs:attribute&gt;
    &lt;xs:attribute name="coords"&gt;
      &lt;xs:simpleType&gt;
  &lt;xs:union memberTypes="Coords AttName"/&gt;
      &lt;/xs:simpleType&gt;
    &lt;/xs:attribute&gt;
    &lt;xs:attribute name="arcrole"&gt;
      &lt;xs:simpleType&gt;
  &lt;xs:union memberTypes="URI AttName"/&gt;
      &lt;/xs:simpleType&gt;
    &lt;/xs:attribute&gt;
    &lt;xs:attribute name="label"/&gt;
    &lt;xs:attribute name="from"/&gt;
    &lt;xs:attribute name="to"/&gt;
    &lt;xs:attribute name="contentType"&gt;
      &lt;xs:simpleType&gt;
  &lt;xs:union memberTypes="ContentType AttName"/&gt;
      &lt;/xs:simpleType&gt;
    &lt;/xs:attribute&gt;
    &lt;xs:attribute name="onSuccess" default="ignoreChildren"&gt;
      &lt;xs:simpleType&gt;
  &lt;xs:union memberTypes="OnSuccess AttName"/&gt;
      &lt;/xs:simpleType&gt;
    &lt;/xs:attribute&gt;
    &lt;xs:attribute name="onFailure" default="warn"&gt;
      &lt;xs:simpleType&gt;
  &lt;xs:union memberTypes="OnFailure AttName"/&gt;
      &lt;/xs:simpleType&gt;
    &lt;/xs:attribute&gt;
  &lt;/xs:attributeGroup&gt;

&lt;/xs:schema&gt;</pre>
<!--OddPage-->

<h2><a id="s_refs" name="s_refs">B. References</a></h2>

<p>This appendix is <em>normative</em>.</p>

<h3><a id="s_norm-refs" name="s_norm-refs">B.1. Normative References</a></h3>
<dl>
  <dt>[<a id="ref_xlink" name="ref_xlink">XLINK</a>]</dt>
    <dd>"<cite><a href="http://www.w3.org/TR/2001/REC-xlink-20010627/">XML
      Linking Language (XLink)</a></cite>", W3C Recommendation, S. DeRose
      <span xml:lang="lt" lang="lt">et al.</span> (editors), 27 June 2001.
      Available at: http://www.w3.org/TR/2001/REC-xlink-20010627<br />
      The <a href="http://www.w3.org/TR/xlink/">latest version</a> is
      available at: http://www.w3.org/TR/xlink</dd>
  <dt>[<a id="ref_uri" name="ref_uri">URI</a>]</dt>
    <dd>"<cite><a href="http://www.rfc-editor.org/rfc/rfc2396.txt">Uniform
      Resource Identifiers (URI): Generic Syntax</a></cite>" (RFC 2396), T.
      Berners-Lee <span xml:lang="lt" lang="lt">et al.</span>, August 1998.
      Available at: http://www.rfc-editor.org/rfc/rfc2396.txt</dd>
  <dt>[<a id="ref_xml" name="ref_xml">XML</a>]</dt>
    <dd>"<cite><a
      href="http://www.w3.org/TR/2000/REC-xml-20001006">Extensible Markup
      Language (XML) 1.0 Specification (Second Edition)</a></cite>", W3C
      Recommendation, T. Bray <span xml:lang="lt" lang="lt">et al.</span>
      (editors), 6 October 2000. Available at:
      http://www.w3.org/TR/2000/REC-xml-20001006<br />
      The <a href="http://www.w3.org/TR/REC-xml">latest version</a> is
      available at: http://www.w3.org/TR/REC-xml</dd>
  <dt>[<a id="ref_name" name="ref_name">NAME</a>]</dt>
    <dd>"<cite><a
      href="http://www.w3.org/TR/1999/REC-xml-names-19990114/">Namespaces in
      XML</a></cite>", W3C Recommendation, T. Bray <span xml:lang="lt"
      lang="lt">et al.</span> (editors), 14 January 1999. Available at:
      http://www.w3.org/TR/1999/REC-xml-names-19990114<br />
      The <a href="http://www.w3.org/TR/REC-xml-names/">latest version</a> is
      available at: http://www.w3.org/TR/REC-xml-names</dd>
  <dt>[<a id="ref_schema" name="ref_schema">SCHEMA</a>]</dt>
    <dd>"<cite><a
      href="http://www.w3.org/TR/2001/REC-xmlschema-2-20010502/">XML Schema
      Part 2: Datatypes</a></cite>", W3C Recommendation, P. V. Biron <span
      xml:lang="lt" lang="lt">et al.</span> (editors), 2 May 2001. Available
      at: http://www.w3.org/TR/2001/REC-xmlschema-2-20010502<br />
      The <a href="http://www.w3.org/TR/xmlschema-2/">latest version</a> is
      available at: http://www.w3.org/TR/xmlschema-2</dd>
</dl>

<h3><a id="s_other-refs" name="s_other-refs">B.2. Other References</a></h3>
<dl>
  <dt>[<a id="ref_html4" name="ref_html4">HTML4</a>]</dt>
    <dd>"<cite><a href="http://www.w3.org/TR/1999/REC-html401-19991224/">HTML
      4.01 Specification</a></cite>", W3C Recommendation, D. Raggett <span
      xml:lang="lt" lang="lt">et al.</span> (editors), 24 December 1999.
      Available at: http://www.w3.org/TR/1999/REC-html401-19991224<br />
      The <a href="http://www.w3.org/TR/html401/">latest version of HTML
      4.01</a> is available at: http://www.w3.org/TR/html401<br />
      The <a href="http://www.w3.org/TR/html4/">latest version of HTML 4</a>
      is available at: http://www.w3.org/TR/html4</dd>
  <dt>[<a id="ref_xhtml" name="ref_xhtml">XHTML</a>]</dt>
    <dd>"<cite><a
      href="http://www.w3.org/TR/2002/REC-xhtml1-20020801/">XHTML™ 1.0 The
      Extensible HyperText Markup Language (Second Edition): A Reformulation
      of HTML 4 in XML 1.0</a></cite>", W3C Recommendation, S. Pemberton
      <span xml:lang="lt" lang="lt">et al.</span>, August 2002. Available at:
      http://www.w3.org/TR/2002/REC-xhtml1-20020801<br />
      The <a href="http://www.w3.org/TR/xhtml1">latest version</a> is
      available at: http://www.w3.org/TR/xhtml1</dd>
  <dt>[<a id="ref_xmod" name="ref_xmod">XHTMLMOD</a>]</dt>
    <dd>"<cite><a
      href="http://www.w3.org/TR/2001/REC-xhtml-modularization-20010410/">Modularization
      of XHTML™</a></cite>", W3C Recommendation, M. Altheim, <span
      xml:lang="lt" lang="lt">et al.</span> (editors), 10 April 2001.
      Available at:
      http://www.w3.org/TR/2001/REC-xhtml-modularization-20010410<br />
      The <a href="http://www.w3.org/TR/xhtml-modularization/">latest
      version</a> is at: http://www.w3.org/TR/xhtml-modularization</dd>
</dl>
<!--OddPage-->

<h2><a id="s_acks" name="s_acks">C. Acknowledgments</a></h2>

<p><em>This section is informative.</em></p>

<p>This document was prepared by
the <acronym title="World Wide Web Consortium">W3C</acronym>
<acronym title="Extensible HyperText Markup Language">XHTML2</acronym> Working Group.
The members at the time of publication of the Note were:</p>

<ul>
<li>Markus Gylling, <a href="http://www.daisy.org">DAISY Consortium</a>
(<acronym title="Extensible HyperText Markup Language">XHTML</acronym> 2 Working Group Co-Chair)</li>
<li>Steven Pemberton, <acronym title="Centrum voor Wiskunde en Informatica"
    xml:lang="nl">CWI</acronym>
(<acronym title="Extensible HyperText Markup Language">XHTML</acronym> 2 Working Group Co-Chair)</li>
<li>Mark Birbeck, Sidewinder Labs (Invited Expert)</li>
<li>Susan Borgrink, Progeny Systems</li>
<li>Christina Bottomley, Society for Technical Communication (STC)</li>
<li>Alessio Cartocci, International Webmasters Association / HTML Writers Guild (IWA-HWG)</li>
<li>Alexander Graf, University of Innsbruck</li>
<li>Tina Holmboe, Greytower Technologies (Invited Expert)</li>
<li>John Kugelman, Progeny Systems</li>
<li>Luca Mascaro, International Webmasters Association / HTML Writers Guild (IWA-HWG)</li>
<li>Shane McCarron, Applied Testing and Technology, Inc. (Invited Expert)</li>
<li>Michael Rawling, IVIS Group Limited</li>
<li>Gregory Rosmaita, Invited Expert</li>
<li>Sebastian Schnitzenbaumer, Dreamlab Technologies AG</li>
<li>Richard Schwerdtfeger,
<acronym title="International Business Machines">IBM</acronym></li>
<li>Elias Torres,
<acronym title="International Business Machines">IBM</acronym></li>
<li>Masataka Yakura, Mitsue-Links Co., Ltd.</li>
<li>Toshihiko Yamakami, ACCESS Co., Ltd. </li>
</ul>

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</html>