title: Regex with negative lookahead to ignore the word "class"
body: <p>I'm getting insane over this, it's so simple, yet I can't figure out the right regex. I need a regex that will match blacklisted words, ie "ass".</p>
  
  <p>For example, in this string:</p>
  
  <pre><code>&lt;span class="bob"&gt;Blacklisted word was here&lt;/span&gt;bass
  </code></pre>
  
  <p>I tried that regex:</p>
  
  <pre><code>((?!class)ass)
  </code></pre>
  
  <p>That matches the "ass" in the word "bass" bot NOT "class".
  This regex flags "ass" in both occurences. I checked multiple negative lookaheads on google and none works.</p>
  
  <p>NOTE: This is for a CMS, for moderators to easily find potentially bad words, I know you cannot rely on a computer to do the filtering.</p>