XS 001 -15 (AB)

The pipeline

<p:declare-step xmlns:err="http://www.w3.org/ns/xproc-error" xmlns:p="http://www.w3.org/ns/xproc" name="pipeline" version="3.0">
   <p:output port="result"/>
   <p:if test="true()">
      <p:identity depends="last">
         <p:with-input>
            <doc/>
         </p:with-input>
      </p:identity>
   </p:if>
   <p:wrap-sequence wrapper="result" name="last"/>
</p:declare-step>