The pipeline
<p:declare-step xmlns:p="http://www.w3.org/ns/xproc" xmlns:x="http://dummy" xmlns:xs="http://www.w3.org/2001/XMLSchema" version="3.0">
<p:output port="result"/>
<p:declare-step type="Q{http://dummy}step" name="step">
<p:input port="source" sequence="true"/>
<p:output port="result" sequence="true"/>
<p:option name="counter" as="xs:integer" required="true"/>
<p:choose>
<p:when test="$counter = 0">
<p:identity/>
</p:when>
<p:otherwise>
<x:step counter="{$counter -1}" name="recursion">
<p:with-input>
<p:inline>
<element/>
</p:inline>
<p:pipe step="step" port="source"/>
</p:with-input>
</x:step>
</p:otherwise>
</p:choose>
</p:declare-step>
<x:step counter="3">
<p:with-input>
<p:empty/>
</p:with-input>
</x:step>
<p:wrap-sequence wrapper="result"/>
</p:declare-step>
Schematron validation
<s:schema xmlns:s="http://purl.oclc.org/dsdl/schematron" queryBinding="xslt2">
<s:pattern>
<s:rule context="/">
<s:assert test="result">The document root is not 'result'.</s:assert>
<s:assert test="count(result/*) = 3">Result does not have three children.</s:assert>
<s:assert test="count(result/element)=3">Result does not have three 'element' children.</s:assert>
</s:rule>
</s:pattern>
</s:schema>
