local _M = {}-- Instantiates a classlocal function _instantiate(class, ...)    -- 抽象类不能实例化    if rawget(class, "__abstract") then        error("asbtract class cannot be instantiated.")    end    -- 单例模式，如果实例已经生成，则直接返回    if rawget(class, "__singleton") then        -- _G[class]值为本class的实例        if _G[class] then            return _G[class]        end    end    local inst = setmetatable({__class=class}, {__index=class})    if inst.__init__ then        inst:__init__(...)    end    --单例模式，如果实例未生成，则将实例记录到类中    if rawget(class, "__singleton") then        if not _G[class] then            _G[class] = inst            -- 对类对象增加实例获取接口            class.getInstance = function ( self )                return _G[class]            end            -- 销毁单例，为后续建立新单例准备            class.destroyInstance = function ( self )                _G[class] = nil            end        end    end    return instend-- LUA类构造函数function _M.class(base)    local metatable = {        __call = _instantiate,    }    -- 先查原型表，然后查父亲类    metatable.__index=function(t, k)        local v = t.__prototype[k]        if v then            return v        end        local parent = t.__parent        if parent then            return parent[k]        end        return nil    end    -- 缓存类的field    metatable.__newindex=function (t,k,v)        rawset(t.__prototype, k, v)    end    local _class = {}    -- __parent 属性缓存父类    _class.__parent = base or {}    -- 存储此类的所有field    _class.__prototype = {}    -- 在class对象中记录 metatable ，以便重载 metatable.__index    _class.__metatable = metatable    -- 将类冷冻，不允许新建删除修改    _class.freeze = function ( self )        local mt = getmetatable(self)        mt.__newindex=function (t,k,v)            error("class is frozen, cannot revise")        end    end    return setmetatable(_class, metatable)end--- Test whether the given object is an instance of the given class.-- @param object Object instance-- @param class Class object to test against-- @return Boolean indicating whether the object is an instance-- @see class-- @see clonefunction _M.instanceof(object, class)    local objClass = object.__class    if not objClass then        return false    end    while objClass do        if objClass == class then            return true        end        objClass = objClass.__parent    end    return falseendreturn _M

local oopclass = require("oopclass")local class = oopclass.classlocal instanceof = oopclass.instanceoflocal superTab =  class()superTab.test = function ( self )    print("superTab test")endsuperTab:freeze()superTab.test2 = function ( self )    print("superTab test2")endlocal tab = class(superTab)local tabObj = tab()tabObj:test()print( instanceof(tabObj, tab) )print( instanceof(tabObj, superTab) )