Lua 单例

Lua中没有类的概念，但是程序猿说要面向对象，然后就有类。程序猿说要继承?和override，然后就有了继承?和?override 。程序猿说要有单例然后有了单例

这里用?Person?和?Student?来作为例子。有少许解释在代码中。

Person类 Person.lua

local Person = {}

function Person:Create()
	-- body
	setmetatable(Person,{__index=Person})
	local p={}
	setmetatable(p,{__index=Person})
	return p
end


function Person:talk( words )
	-- body
	print("Person say " ..words)
end

function Person:jump()
	print("Person jump")
end

return Person

派生类 Student.lua

local Student = {}

local Person= require("Person")


local m_instance = nil

local m_name="Student"

function Student:SharedInstance()
	print("Student:SharedInstance")
	-- body
	if(m_instance==nil) then
		print("m_instance==nil new one")
		setmetatable(Student,{__index=Person})--设置Student的 __index 为Person，这样在Student中找不到的就会去Person中找
		m_instance={}
		setmetatable(m_instance,{__index=Student})--设置s 的 __index 为Student
	end
	return m_instance
end


function Student:run(speed)
	print(self.m_name .. " run speed=" .. speed)
end

function Student:jump()
	print(self.m_name .. " jump");
end

return Student

测试代码test.lua

local Student = require("Student")
local Person = require("Person")



local student1=Student:SharedInstance()
student1.m_name="student1"
student1:talk(" wahaha")
student1:jump()
student1:run(123)

local student2=Student:SharedInstance()
student2.m_name="student2"
student2:talk(" wahaha2")
student2:jump()
student2:run(1232)

local person1 = Person:Create()
person1:talk(" 61")
person1:jump()

代码下载

http://pan.baidu.com/s/1o6jEgvK

http://download.csdn.net/detail/cp790621656/9239899