The pipeline
<p:declare-step xmlns:p="http://www.w3.org/ns/xproc" version="3.0">
<p:output port="result"/>
<p:choose>
<p:with-input port="source"><doc xmlns=""/></p:with-input>
<p:when test="true()">
<p:identity>
<p:with-input><true xmlns=""/></p:with-input>
</p:identity>
</p:when>
<p:otherwise>
<p:identity>
<p:with-input><false xmlns=""/></p:with-input>
</p:identity>
</p:otherwise>
</p:choose>
</p:declare-step>
