title: Regular expression to not match file two file types in Bash
body: <p>I'm trying to do a list in bash of files that are not <code>.html</code> or <code>.js</code></p>
  
  <p>I've tired both of the following methods but neither work?</p>
  
  <pre><code>ls !(*.html|*.js)
  
  
  ls | grep -v '\.(html|js)$'
  </code></pre>