code: function (points, point, index, len) {
                  if (this.addedIndex < index && this.addedIndex < len - 1) {
                      points.push(point);
                      this.addedIndex = index;
                  }
              }
docs: Internal. Applications should not call this method.
  Adds an element to an array preventing duplication
  @param {Location[] | Position[]} points
  @param {Location | Position} point
  @param {Number} index The index of the Point from the source array
  @param {Number} len The length of the source array