se/SE/schema/WPS_Functions/dita-ot/dita-ot-3.0.4/docsrc/reference/preprocess-conref.dita

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<!DOCTYPE concept PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
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<concept id="preprocess-conref" xml:lang="en-US">
  <title>Conref (conref)</title>
  <shortdesc>The <codeph>conref</codeph> step resolves conref attributes, processing only the DITA maps or topics that
    use the @conref attribute. This step is implemented in XSLT.</shortdesc>
  <conbody>
    <section>
      <p>The values of the <xmlatt>id</xmlatt> attribute on referenced content are changed as the elements are pulled
        into the new locations. This ensures that the values of the <xmlatt>id</xmlatt> attribute within the referencing
        topic remain unique.</p>
      <p>If an element is pulled into a new context along with a cross reference that references the target, both the
        values of the <xmlatt>id</xmlatt> and <xmlatt>xref</xmlatt> attributes are updated so that they remain valid in
        the new location. For example, a referenced topic might include a section as in the following example: <fig>
          <title>Referenced topic that contains a section and cross reference</title>
          <codeblock>&lt;topic id="referenced_topic">
  &lt;title>...&lt;/title>
  &lt;body>
    &lt;section id="sect">&lt;title>Sample section&lt;/title>
      &lt;p>Figure &lt;xref href="#referenced_topic/fig"/> contains a code sample that demonstrates ... .&lt;/p>
      &lt;fig id="fig">&lt;title>Code sample&lt;/title>
        &lt;codeblock>....&lt;/codeblock>
      &lt;/fig>
    &lt;/section>
  &lt;/body>
&lt;/topic></codeblock>
        </fig></p>
      <p>When the section is referenced using a <xmlatt>conref</xmlatt> attribute, the value of the <xmlatt>id
        </xmlatt>attribute on the <xmlelement>fig</xmlelement> element is modified to ensure that it remains unique in
        the new context. At the same time, the  <xmlelement>xref</xmlelement> element is also modified so that it
        remains valid as a local reference. For example, if the referencing topic has an <xmlatt>id </xmlatt> set to
        "new_topic", then the conrefed  element may look like this in the intermediate
          document <xmlelement>section</xmlelement>.
        <fig>
          <title>Resolved conrefed <xmlelement>section</xmlelement> element after the conref step</title>
          <codeblock>&lt;section id="sect">&lt;title>Sample section&lt;/title>
    &lt;p>Figure &lt;xref href="#new_topic/d1e25"/> contains a code sample that demonstrates ... .&lt;/p>
    &lt;fig id="d1e25">&lt;title>Code sample&lt;/title>
        &lt;codeblock>....&lt;/codeblock>
    &lt;/fig>
&lt;/section></codeblock>
        </fig></p>
      <p>In this case, the value of the <xmlatt>id </xmlatt> attribute on the <xmlelement>fig</xmlelement> element has
        been changed to a generated value of "d1e25". At the same time, the <xmlelement>xref</xmlelement> element has
        been updated to use that new generated ID, so that the cross reference remains valid.</p>
    </section>
  </conbody>
</concept>