Lua面向对象 --- 多态

多态，简单的理解就是事物的多种形态。专业的术语说就是：同一个实现接口，使用不同的实例而执行不同的操作。

工程结构:

BaseRoom.lua:

 BaseRoom = {}

 function BaseRoom:new()
     self = {}
     setmetatable(self,BaseRoom)
     BaseRoom.__index = BaseRoom
     return self
 end

 --对该方法的调用体现了多态
 function BaseRoom:Size()
     return
 end

 function BaseRoom:GetSize()
     return self:Size()*
 end

 return BaseRoom

MarryRoom.lua:

 require "BaseRoom"

 MarryRoom = {}

 function MarryRoom:new()
     setmetatable(MarryRoom, BaseRoom)
     BaseRoom.__index = BaseRoom

     self = {}
     setmetatable(self,MarryRoom)
     MarryRoom.__index = MarryRoom

     return self
 end

 --对该方法的调用提现了多态
 function MarryRoom:Size()
     return
 end

 return MarryRoom

StarRoom.lua:

 require "BaseRoom"

 StarRoom = {}

 function StarRoom:new()
     setmetatable(StarRoom,BaseRoom)
     BaseRoom.__index = BaseRoom

     self = {}
     setmetatable(self,StarRoom)
     StarRoom.__index = StarRoom

     return self
 end

 --对该方法的调用体现了多态
 function StarRoom:Size()
     return
 end

 return StarRoom

码云上的相关工程:https://gitee.com/luguoshuai/LearnLua