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HTML is good for debugging, but is unsuitable for application use.
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To see the non HTML representation of the XML format, set format=xml.
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<?xml version="1.0"?>
<api>
  <query-continue>
    <alllinks alcontinue="R_Native_API" />
  </query-continue>
  <query>
    <alllinks>
      <l ns="0" title="Code Coverage Tool for R" />
      <l ns="0" title="Distributed Computing Working Group" />
      <l ns="0" title="Distributed Computing Working Group Progress Report 2016" />
      <l ns="0" title="Initial Survey of API Usage" />
      <l ns="0" title="Native API stats of R.h" />
      <l ns="0" title="Native API stats of Rinternals.h with USE R INTERNALS" />
      <l ns="0" title="Native API stats of Rinternals.h without USE R INTERNALS" />
      <l ns="0" title="Native API stats of all header files" />
      <l ns="0" title="R Certification" />
      <l ns="0" title="R Consortium and the R Community Code of Conduct" />
    </alllinks>
  </query>
</api>