title: How to iterate over archive in boost::serialization
body: <p>I loaded multiple data into <code>boost::archive::text_oarchive</code>, now I need to extract the data.
  But because the archive contains multiple records, I would need an iterator.</p>
  
  <p>something like</p>
  
  <pre><code>//input archive
  boost::archive::text_iarchive iarch(ifs);
  
  //read until the end of file
  while (!iarch.eof()){
  
  //read current value
  iarch &gt;&gt; temp;
  ...//do something with temp
  
  }
  </code></pre>
  
  <p>is there any standard way to iterate over elements of the archive?
  I found only <code>iarchive.iterator_type</code>, but is it what I need and how do I use it?</p>