function IceyMaze(width, height, regularity) {
      var _this17;
      if (regularity === void 0) {
        regularity = 0;
      }
      _this17 = _Map6.call(this, width, height) || this;
      _this17._regularity = regularity;
      _this17._map = [];
      return _this17;
    }
Icey's Maze generator
See http://roguebasin.com/index.php/Simple_maze for explanation