Lua的类有点像javascript,但是更简明灵活,table即对象,对象就是类。Metatables比起ruby里的MetaClass更加好用,缺点是实例化和继承的代码有点多,
不像ruby里的“<”和“<<”,继承链就是查找方法时的方法链。
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Account={ test1=function(a) print( "Account test1" ) end } Account.test2=function(a) print( "Account test2" ) end function Account.test3(a) print( "Account test3" ) end function Account: new (o) --类的实例化 o = o or {} setmetatable(o, self) self.__index = self return o end function Account.print0(o,a) print(a) end function Account:print1(a) print(a) end --方法定义测试 Account.test1() Account.test2() Account.test3() --类测试 acc=Account: new () acc.test1() acc.print0(acc, "dot print0" ) acc:print0( "not dot print0" ) acc.print1(acc, "dot print1" ) acc:print1( "not dot print1" ) acc.specialMethod=function(specialMethodTest) print(specialMethodTest) end acc.specialMethod( "smt test" ) --继承测试 SpecialAccount = Account: new () s = SpecialAccount: new {limit=1000.00} --多重继承测试 Named = {} function Named:getname () return self.name end function Named:setname (n) self.name = n end local function search (k, plist) for i=1, table.getn(plist) do local v = plist[i][k] if v then return v end end end function createClass (...) local c = {} -- new class setmetatable(c, {__index = function (t, k) return search(k, arg) end}) c.__index = c function c: new (o) o = o or {} setmetatable(o, c) return o end return c end NamedAccount = createClass(Account, Named) account = NamedAccount: new {name = "Paul" } print(account:getname()) |