将JavaScript oop代码翻译为Lua

我正在尝试将一堆代码从JavaScript翻译成Lua。不过我还是被下一个问题卡住了。我不理解Lua面向对象的语法。有人能告诉我正确的语法是什么吗？谢谢

//=======================================================
//=======================================================
//=======================================================
// The TMaze object
//------------------------------------------------------------------------------ Ctor
function TMaze(nHigh, nWide) {
    this.high = nHigh;
    this.wide = nWide;
    this.ary = TMazeArray(nHigh, nWide);
    this.totRooms = gnHigh * gnWide;  // less (short) bottom line
    this.curRoomCnt = 0;  // rooms that have been visited/door opened
    this.GetCell = function(x,y) {return this.ary[y][x];}
    this.SetCell = function(x,y,value) {this.ary[y][x] = value;}
    this.HasCellBit = function(x,y,value) {return ((this.ary[y][x] & value) == value);}
    this.SetCellBit = function(x,y,value) {this.ary[y][x] |= value;}
    this.ClearCellBit = function(x,y,value) {this.ary[y][x] &= ~value;}
    this.ToggleCellBit = function(x,y,value) {this.ary[y][x] ^= value;}
    this.IsEmptyCellAt = IsEmptyCellAt;  // some member fns, defined below
    this.IsValidXY = IsValidXY;
    this.GetNewXY = GetNewXY;
}
//----------- TRUE if cell in that direction is empty and valid
//
function IsEmptyCellAt(x, y, dir) {
    var o = this.GetNewXY(x, y, dir);
    if (!this.IsValidXY(o.newX, o.newY))   return (false); 
    if (this.GetCell(o.newX, o.newY) != 0)  return (false);
    return true;  // yes, it's possible to move into that cell
}
//------------------------------------------------------------------------------
// return -1 if that would be an invalid move (off the board)
// true if X,Y is on the board
//
function IsValidXY(x, y) {
    if (y < 0) return (false);
    if (y > this.high-1) return (false);
    if (x < 0) return (false);
    if (x > this.wide-1) return (false);
//    if (y & 1) {  // on off Y, max X an maxY are 1 less
//        if (x > this.wide-2) return (false);
//        if (y > this.high-2) return (false);
//    }
    return true;  // possible to move into that direction
}
//------------------------------------------
// If I move in a direction, what are the new X,Y values?
// Return an object with newX and newY properties
//
function GetNewXY(x, y, dir) {
    var oRet = {"newX":-1, "newY":-1, "isValid":false};
    var newX = x;
    var newY = y;
    newX += ganDeltaX[dir];  // add the deltas
    newY += ganDeltaY[dir];
    if (this.IsValidXY(newX, newY)) {
        oRet.newX = newX;
        oRet.newY = newY;
        oRet.isValid = true;
    }
    return oRet;
}

你可以忽略按位操作，因为我已经想好了如何翻译它。我最关心的是oop的东西。

[编辑]

这是我到目前为止所拥有的，但它崩溃了。

--=======================================================
--=======================================================
-- The TMaze object
-------------------------------------------------------------------------------- Ctor
TMaze =
{
    high = gnHigh,
    wide = gnWide,
    ary = TMazeArray(gnHigh, gnWide),
    totRooms = gnHigh * gnWide,         -- less (short) bottom line
    curRoomCnt = 0,                     -- rooms that have been visited/door opened
}
TMaze.GetCell = function(self,x,y) return self.ary[y][x] end
TMaze.SetCell = function(self,x,y,value) self.ary[y][x] = value end
TMaze.HasCellBit = function(self,x,y,value) return bit.band(self.ary[y][x], value) == value end
TMaze.SetCellBit = function(self,x,y,value) self.ary[y][x] = bit.bor(self.ary[y][x], value) end
TMaze.ClearCellBit = function(self,x,y,value) self.ary[y][x] = bit.band(self.ary[y][x], bit.bnot(value)) end
TMaze.ToggleCellBit = function(self,x,y,value) self.ary[y][x] = bit.bxor(self.ary[y][x], value) end
--=======================================================
------------- TRUE if cell in that direction is empty and valid
--
TMaze.IsEmptyCellAt = function(self, x, y, dir)
    local o = self.GetNewXY(self, x, y, dir)
    if (not self.IsValidXY(self, o.newX, o.newY)) then return 0 end
    if (self.GetCell(self, o.newX, o.newY) ~= 0) then return 0 end
    return 1  -- yes, it's possible to move into that cell
end
--------------------------------------------------------------------------------
-- return -1 if that would be an invalid move (off the board)
-- true if X,Y is on the board
--
TMaze.IsValidXY = function(self, x, y)
    if (y < 1) then return 0 end
    if (y > self.high) then return 0 end
    if (x < 1) then return 0 end
    if (x > self.wide) then return 0 end
--  if (y & 1) then  -- on off Y, max X an maxY are 1 less
--      if (x > self.wide-2) then return 0 end
--      if (y > self.high-2) then return 0 end
--  end
    return 1  -- possible to move into that direction
end
--------------------------------------------
-- If I move in a direction, what are the new X,Y values?
-- Return an object with newX and newY properties
--
TMaze.GetNewXY =  function(self, x, y, dir)
    local oRet = {newX=-1, newY=-1, isValid=0}
    local newX = x
    local newY = y
    newX = newX + ganDeltaX[dir]  -- add the deltas
    newY = newY + ganDeltaY[dir]
    if (self.IsValidXY(self, newX, newY)) then
        oRet.newX = newX
        oRet.newY = newY
        oRet.isValid = 1
    end
    return oRet
end