title: C++: How to extract a string from RapidXml
body: <p>In my C++ program I want to parse a small piece of XML, insert some nodes, then extract the new XML (preferably as a <code>std::string</code>).<br>
  <a href="http://rapidxml.sourceforge.net/" rel="nofollow noreferrer">RapidXml</a> has been recommended to me, but I can't see how to retrieve the XML back as a text string.<br>
  (I could iterate over the nodes and attributes and build it myself, but surely there's a build in function that I am missing.)<br>
  Thank you.</p>