title: PhpStorm Structural Search, Contained in constraints syntax, how to search for tag, enclosed by tag?
body: <p>I want to search for a <code>footag</code> with attribute <code>foo=bar</code>, enclosed by <code>bartag</code> with <code>other=stuff</code>.</p>
  
  <p>like a</p>
  
  <pre><code>&lt;bartag other="stuff"&gt;
       ...
       &lt;footag foo="bar"&gt;
       ...
  &lt;/bartag&gt;
  </code></pre>
  
  <p>In PhpStorm structural search I find <a href="https://i.stack.imgur.com/TXb2W.png" rel="nofollow noreferrer">this template</a>. I really was wondering how it works and have find out that it's drive by this <a href="https://i.stack.imgur.com/zik97.png" rel="nofollow noreferrer">magical condition</a></p>
  
  <pre><code>&lt;'_tag:[regex( ul|ol )] /
  </code></pre>
  
  <p>What is this syntax? How it works?</p>