local type = typelocal rawset = rawsetlocal setmetatable = setmetatablelocal traceCount = 0local tracebacks = setmetatable({}, {__mode = "k"})local function class(classname, super)    local cls = {}    cls.classname = classname    cls.class = cls    cls.Get = {}    cls.Set = {}        local Get = cls.Get    local Set = cls.Set    if super then        -- copy super method         for key, value in pairs(super) do            if type(value) == "function" and key ~= "ctor" then                cls[key] = value            end        end        -- copy super getter        for key, value in pairs(super.Get) do            Get[key] = value        end                -- copy super setter        for key, value in pairs(super.Set) do            Set[key] = value        end                cls.super = super    end    function cls.__index(self, key)        local func = cls[key]        if func then           return func        end        local getter = Get[key]        if getter then            return getter(self)        end        return nil    end    function cls.__newindex(self, key, value)        local setter = Set[key]        if setter then            setter(self, value or false)            return        end        if Get[key] then            assert(false, "readonly property")        end                rawset(self, key, value)    end    function cls.new(...)        local self = setmetatable({}, cls)        local function create(cls, ...)            if cls.super then                create(cls.super, ...)            end            if cls.ctor then                cls.ctor(self, ...)            end        end        create(cls, ...)                -- debug        traceCount = traceCount + 1        tracebacks[self] = traceCount        return self    end    -- compat    cls.dtor = nil    function cls.delete(self)        if tracebacks[self] < 0 then return end        local destroy        destroy = function(cls)            if cls.dtor then                cls.dtor(self)            end            if cls.super then                destroy(cls.super)            end        end        destroy(cls)        tracebacks[self] = -tracebacks[self]    end    return clsendreturn class

local class = require "class"local Point = class("Point")function Point:ctor(x, y)    self.x = x    self.y = yendfunction Point.Get:x() return self._x endfunction Point.Set:x(value) self._x = value endfunction Point.Get:y() return self._y endfunction Point.Set:y(value) self._y = value endlocal p = Point.new(10, 20)print(p.x, p.y)p.x = 5p.y = 5print(p.x, p.y)

local class = require "class"local Sprite = class("Sprite")function Sprite:ctor()    self.cobj = cc.Sprite:create()endfunction Sprite.Get:x() return self.cobj:getPositionX() endfunction Sprite.Set:x(value) self.cobj:setPositionX(value) endfunction Sprite.Get:y() return self.cobj:getPositionY() endfunction Sprite.Set:y(value) self.cobj:setPositionY(value) endlocal obj = Sprite.new()obj.x = 30obj.y = 40obj.y = obj.x