title: Substrings from iterable node
body: <p>Please consider this sample file: <a href="http://www.w3schools.com/dom/books.xml" rel="nofollow">http://www.w3schools.com/dom/books.xml</a></p>
  
  <p>This XPath expression <code>//title/text()</code>, returns:</p>
  
  <blockquote>
    <p>Everyday Italian<br>
    Harry Potter<br>
    XQuery Kick Start<br>
    Learning XML  </p>
  </blockquote>
  
  <p>Now I want just the first names, and try: <code>tokenize(//title/text(),' ')[1]</code>, which returns:</p>
  
  <blockquote>
    <p>Too many items  </p>
  </blockquote>
  
  <p>OTOH <code>tokenize((//title/text())[1],' ')[1]</code> returns first name for first node.</p>
  
  <p>How can I get substrings with XPath while iterating nodes?</p>