title: How do I turn any regex into an complement of itself without complex hand editing?
body: <p>The following are pseudo examples, not real regex, but still an example of what I mean:</p>
  
  <hr>
  
  <pre><code>.* (anything)
  
  -.* (NOT anything)
  </code></pre>
  
  <hr>
  
  <pre><code>[A-Z] (Any letter A to Z, caps only)
  
  -[A-Z] (NOT any letter A to Z, caps only)
  </code></pre>
  
  <hr>
  
  <p><strong>EDIT:</strong> Changed inverse into complement in the question. Here's where the change was made: "turn any regex into an <strong>complement</strong> of itself "</p>