title: How do I traverse all the nodes in a YAML tree in Ruby?
body: <p>I am loading an arbitrary YAML document, and want to walk every node in the tree.  I don't know how nested the tree is beforehand, so I can't just use a simple each statement to walk all the nodes.</p>
  
  <p>Here is how I'm loading the document:</p>
  
  <pre><code>tree = File.open( "#{RAILS_ROOT}/config/locales/es.yml" ){ |yf| YAML::load (yf)}
  </code></pre>