title: Join multiple concatenations of attributes with node values using xpath
body: <p>I have the following xml content:</p>
  
  <pre><code>&lt;ns2:ItemAttributes xml:lang="de-DE"&gt;
      &lt;ns2:Creator Role="Role1"&gt;Creator One&lt;/ns2:Creator&gt;
      &lt;ns2:Creator Role="Role2"&gt;Creator Two&lt;/ns2:Creator&gt;
      &lt;ns2:Creator Role="Role3"&gt;Creator Three&lt;/ns2:Creator&gt;
  &lt;/ns2:ItemAttributes&gt;
  </code></pre>
  
  <p>I'm trying to format and combine this into one line using xpath. 
  Something like:</p>
  
  <pre><code>string-join(//ns2:Creator/concat(./text(), @Role), ', ')
  </code></pre>
  
  <p>I think, i'm somewhere close, because this:</p>
  
  <pre><code>string-join(//ns2:Creator/@Role , ', ')
  </code></pre>
  
  <p>works and gives me a comma-separated list of roles: Role1, Role2, Role3</p>
  
  <p>and this</p>
  
  <pre><code>string-join(//ns2:Creator/node(), ', ')
  </code></pre>
  
  <p>combines the values of creators: "Creator One, Creator Two, Creator Three".</p>
  
  <p>I'd like the final output of</p>
  
  <pre><code>Role1: Creator One, Role2: Creator Two, Role3: Creator Three
  </code></pre>
  
  <p>Could you please help.</p>