title: Regex and JavaScript strings
body: <p>I am working with a set of blood pressure readings, for example</p>
  
  <pre><code>lines[50] = '(523,112)';
  </code></pre>
  
  <p>and I am using</p>
  
  <pre><code>readings[i] = lines[i].slice(5,8);
  </code></pre>
  
  <p>to extract the second 3 digit number.  How can this be done with a regular expression?</p>