title: Starting the week on Monday with isoWeekday()
body: <p>I'm creating a calendar where I print out weeks in a tabular format. One requirement is that I be able to start the weeks either on Monday or Sunday, as per some user option. I'm having a hard time using moment's <a href="http://momentjs.com/docs/?codekitCB=401206465.298830#/get-set/iso-weekday/">isoWeekday</a> method.</p>
  
  <pre><code>// Start of some date range. Can be any day of the week.
  var startOfPeriod = moment("2013-06-23T00:00:00"),
  
      // We begin on the start of the first week.
      // Mon Tues Wed Thur Fri Sat Sun
      // 20  21   22  23   24  25  26
      begin = moment(startOfPeriod).isoWeekday(1); // will pull from user setting
  
  console.log(begin.isoWeekday()); // 1 - all good
  
  // Let's get the beginning of this first week, respecting the isoWeekday
  begin.startOf('week');
  
  console.log(begin.isoWeekday()); // 7 - what happened ???
  
  // Get column headers
  for (var i=0; i&lt;7; i++) {
      console.log(begin.format('ddd')); // I want Monday first!
      begin.add('d', 1);
  }
  </code></pre>
  
  <p><a href="http://jsfiddle.net/PxAUd/">jsFiddle</a></p>
  
  <p><strong>EDIT</strong> I misunderstood what <code>isoWeekday</code> was actually doing. I thought it set the "which day of the week is the first day of the week" variable (that doesn't exist). What it actually does is simply changes the day of the week, just like <code>moment.weekday()</code>, but uses a 1-7 range instead of the 0-6.</p>