title: What does this regexp mean - "\p{Lu}"?
body: <p>I stumble across this regular expression in c# I would like to port to javascript, and I do not understand the following:</p>
  
  <pre><code>[-.\p{Lu}\p{Ll}0-9]+
  </code></pre>
  
  <p>The part I have a hard time with is of course <code>\p{Lu}</code>. All regexp websites I visited never mention this modifier. </p>
  
  <p>Any idea?</p>