code: function(comparator, comparatorNullsFirst)
    {
      var cmp = comparator ? createComparator( comparator, comparatorNullsFirst ) : this.comparator;
  
      if ( !isSorted( cmp, this ) )
      {
        this.map.sort( cmp );
  
        this.trigger( Collection.Events.Sort, [this] );
      }
  
      return this;
    }
docs: Documented in Collection.js