title: perl regex match any number that is not
body: <p>given a string:</p>
  
  <pre><code>//foo.bar/baz/123/index.html
  </code></pre>
  
  <p>I am trying to match the number after baz, so long as it is not 123.</p>
  
  <pre><code>//foo.bar/baz/124/index.html (WOULD MATCH)
  //foo.bar/baz/123/index.html (WOULD NOT MATCH)
  </code></pre>
  
  <p>How can I express this?  I keep trying things like:</p>
  
  <pre><code>/baz\/d+^(123)/index/
  </code></pre>
  
  <p>but have not been successful.  Any help is appreciated!</p>