title: SSI $DOCUMENT_URI regular expression
body: <p>I have a nav.shtml file in which I am setting a class on the current menu item as follows:</p>
  
  <pre><code>Faculty'&gt;http://root/level1/level2/page.shtml"&gt;Faculty &amp; Staff
  </code></pre>
  
  <p>This is fine for the top-level pages, but a few have subpages and I would like to be able to set the class on the top-level menu item if the current page is a subpage as well.  E.g. There is a "Faculty/Staff" menu item which goes to an overview page, faculty.shtml, then there are some links on that page to individual faculty/staff pages in a subdirectory.  If I'm looking at one of the individual subpages, I still want the class to get set on the "Faculty/Staff" menu item.</p>
  
  <p>So, I need something like:</p>
  
  <pre><code>"if $DOCUMENT_URI=/level1/level2/page.shtml *or* if $DOCUMENT_URI=/level1/level2/level3/*.shtml".  
  </code></pre>
  
  <p>I can't seem to figure out the correct syntax...  Can anyone help me out?</p>