code: function rangeExtents(ranges) {
    var start = Number.MAX_VALUE;
    var end = Number.MIN_VALUE;
    ranges.map(function (_ref) {
      var rs = _ref.start,
          re = _ref.end;
  
      start = Math.min(start, rs);
      end = Math.max(end, re);
    });
    return { start: start, end: end };
  }
docs: cq Engine Util
  
  Utility functions