Declare-step-012a (AB)

The pipeline

<p:declare-step xmlns:err="http://www.w3.org/ns/xproc-error" xmlns:p="http://www.w3.org/ns/xproc" xmlns:test="http://test" version="3.0">
   <p:output port="result"/>
   <p:declare-step type="test:step-2">
      <p:output port="result"/>
      <p:identity>
         <p:with-input>
            <doc1/>
         </p:with-input>
      </p:identity>
   </p:declare-step>
   <p:declare-step type="test:step-1">
      <p:output port="result"/>
      <p:declare-step type="test:step-2">
         <p:output port="result"/>
         <p:identity>
            <p:with-input>
               <doc/>
            </p:with-input>
         </p:identity>
      </p:declare-step>
      <test:step-2/>
   </p:declare-step>
   <test:step-1 name="one"/>
   <test:step-2 name="two"/>
   <p:wrap-sequence wrapper="result">
      <p:with-input pipe="@one @two"/>
   </p:wrap-sequence>
</p:declare-step>