title: Ruby Regex error
body: <p>My regex:</p>
  
  <pre class="lang-none prettyprint-override"><code>https?://[\w-]+(?:\.[\w-]+)+(?:/[\w-]+)*(?:[./%?=&amp;#-]\w+)+)?
  </code></pre>
  
  <p>In Ruby, I get the following error:</p>
  
  <pre class="lang-none prettyprint-override"><code>unmatched close parenthesis:/https?://[\w-]+(?:\.[\w-]+)+(?:/[\w-]+)*(?:[./%?=&amp;#-]\w+)+)?/'
  </code></pre>
  
  <p>How can I fix this?</p>