docs: function(sel, range) {
              var ranges = sel.getAllRanges();
              sel.removeAllRanges();
              for (var i = 0, len = ranges.length; i < len; ++i) {
                  if (!rangesEqual(range, ranges[i])) {
                      sel.addRange(ranges[i]);
                  }
              }
              if (!sel.rangeCount) {
                  updateEmptySelection(sel);
              }
          }