title: Regex matching multiple negative lookaheads
body: <p>I'm trying to match a string (using a Perl regex) only if it doesn't start with &quot;abc:&quot; or &quot;defg:&quot;, but I can't seem to find out how. I've tried something like</p>
  <pre><code>^(?:(?!abc:)|(?!defg:))
  </code></pre>