title: Regex to exclude certain file extensions
body: <p>similar questions have been asked, but they miss one thing I need to do and I can't figure it out.</p>
  
  <p>I need to find all files that do NOT have either a tif, or tiff extension, but I DO need to find all others including those that have no extension. I got the first part working with the regex below, but this doesn't match files with no extension.</p>
  
  <pre><code>^(.+)\.(?!tif$|tiff$).+$
  </code></pre>
  
  <p>That works great, but I need the following to work.</p>
  
  <pre><code>filename.ext MATCH
  filename.abc MATCH
  filename.tif FAIL
  filename     MATCH
  </code></pre>
  
  <p>Thanks :)</p>