docs: function point() {
    var args = mlutil.asArray.apply(null, arguments);
    switch(args.length) {
    case 0:
      throw new Error('missing latitude and longitude for point');
    case 1:
      return new PointRegionDef([args[0]]);
    case 2:
      return new PointRegionDef([new LatLongDef(args[0], args[1])]);
    default:
      throw new Error('too many arguments for point: '+args.length);
    }
  }