title: match two exact characters in regex or (pipe) clause
body: <p>I'm trying to parse shorthand notation into an integer representation. This works fine for Hours, Seconds, and Minutes, but not with Milliseconds, where the regex is failing to match.</p>
  
  <p><code>'50ms'.match(/^(\d+)([MS|S|M|H|ms|s|m|h])$/);</code></p>
  
  <p>I wasn't sure how to phrase the question correctly, but i did perform several searches prior to asking here.</p>
  
  <p><a href="https://jsfiddle.net/oxwaodyh/1/" rel="nofollow" title="jsfiddle">jsfiddle</a></p>