code: function (item) {
  		var index = -1;
  		this.items.forEach(function (comparedTo, newIndex) {
  			if (this.comparator(comparedTo, item) <= 0) {
  				index = newIndex;
  				return false;
  			}
  		}, this);
  		return index;
  	}
docs: Determine where a newly inserted item would fit in this collection. Find
  the index of the item to insert after, or -1 to insert at the first
  index.
  @param {*} item Item to be added to collection
  @return {int} Index of the item to insert after
  @todo Rephrase