print("hello world")local function fact(n)	if n == 0 then		return 1	else		return n * fact(n-1)	endendlocal a = fact(5)print(a)print(b)--。Lua中有8个基本类型分别为：nil、boolean、number、string、userdata、function、thread和tableprint(type("hello world"))print(type(4.6))print(type(print))print(type(type))print(type(true))print(type(nil))print(type(type(x)))testTable = {}testTable = nilfunction testNil()	if  testTable == nil then		print("nil is false")	else		print("nil is not false")	endendtestNil()--[[这些操作符返回结果为false或者true；==和~=比较两个值，如果两个值类型不同，Lua认为两者不同；nil只和自己相等。Lua通过引用比较tables、userdata、functions。也就是说当且仅当两者表示同一个对象时相等。]]a = {}; a.x = 1; a.y = 0;b = {}; b.x = 1; b.y = 0;c = a;function testEqual()	if a == b then		print("a == b")	elseif c == a then		print("a == c")	endendtestEqual()--[[逻辑运算符认为false和nil是假（false），其他为真，0也是true. and和or的运算结果不是true和false，而是和它的两个操作数相关]]print(4 and 5)print(4 and false)print(false and nil)print(false or nil)print(true or true)x = x or 10print(x)--三元运算符，前提条件是b不为假a = 1; b = true; c = 2;print((a and b) or c)--not的结果一直返回false或者true print(not false)--..字符串连接，如果操作数为数字，Lua将数字转成字符串。print("hello" .. " world")print(1 .. 2)--对于table usedata，function，lua是作引用比较的；nil只与他自身相等a = {}a.x = 1; a.y = 2b = {}b.x = 1; b.y = 2c = aprint(a == b)print(a ~= b)print(a == c)--表的构造local days = {"sun", "mon", "tue", "wed", "thu", "fri", "sat"}print(days[1])local vec = {x = 1, y = 2, "sun"}print(vec[1])print(vec["x"])print(vec.y)--表索引local a = {["x"]=3, ["y"]=4}a["z"] = 5a.w = 6print(a.x)print(a["y"])print(a.z)print(a.w)--list风格初始化和record风格初始化是这种一般初始化的特例: --{x=0, y=0} <--> {["x"]=0, ["y"]=0} --{"red", "green", "blue"} <--> {[1]="red", [2]="green", [3]="blue"} --链表local single_list = nillocal function make_list(begin, count)	for i = 1, count, 1 do		single_list = {value = begin, next = single_list}		begin = begin + 1	endendmake_list(1, 10)local function print_list()	local temp_list = single_list;	while temp_list ~= nil do		print("list value:" .. temp_list.value)		temp_list = temp_list.next;	endendprint_list()function test_do()	--Lua可以对多个变量同时赋值，变量列表和值列表的各个元素用逗号分开，赋值语句右边的值会依次赋给左边的变量。	--a, b = 10, 2*x   <-->   a=10; b=2*x	--遇到赋值语句Lua会先计算右边所有的值然后再执行赋值操作，所以我们可以这样进行交换变量的值	do		x, y = y, x	end	--if	do		if true then				elseif false then				else				end	end	--while	do		while true do		end	end	--for	do		for i = 1, 10, 1 do			print(i)		end	endend--泛型forfunction foreach()	local list = {"2", "3", "4"}	for i,v in ipairs(list) do		print("value:" .. v)	end		for i in pairs(list) do		print("kay:" .. i)	endendforeach()--Lua语法要求break和return只能出现在block的结尾一句（也就是说：作为chunk的最后一句，或者在end之前，或者else前，或者until前）--[[function foo () 	return  --<< SYNTAX ERROR 	-- 'return' is the last statement in the next block 	do return end -- OK 	...   -- statements not reached end ]]--可变参数:Lua函数可以接受可变数目的参数，和C语言类似在函数参数列表中使用三点（...）表示函数有可变的参数。Lua将函数的参数放在一个叫arg的表中，除了参数以外，arg表中还有一个域n表示参数的个数。function pair_fun(a, b, ...)	for i, v in ipairs(arg) do		print("arg:" .. i .. " " .. v)	endendpair_fun(1,2,3)pair_fun(1,2,3, 4)pair_fun(1,2)print(math.sin(1))--闭包function package()	local old_sin = math.sin	local k = math.pi/180	math.sin = function(x)		return old_sin(x*k)	endendpackage()print(math.sin(1))--非全局函数lib = {}lib.foo = function(x, y) 	return x+ y endprint(lib.foo(1,1))function lib.goo(x , y)--另一种语法方式	return x - yendprint(lib.goo(1,2))--函数定义的两种方式local f = function()endfunction f()end--闭包函数调用function list_iter(t)	local i = 0	local n = table.getn(t)	return function()		i = i + 1		if i <= n then			return t[i]		end	endendfunction use_iter()	local t = {10,20,30}	iter = list_iter(t)	while true do		local element = iter()		if element == nil then			break		end		print(element)	endenduse_iter()--loadstringlocal f = loadstring("local a = 1; return a + 2")print(f())--assertassert(true)--errorlocal function foo()	--if false then		error()		debug.traceback()	--endendfunction process_call()	foo()end--process_call()--多维数组mt = {}function create_mt()	for i = 1, 10 do		mt[i] = {}		for j = 1, 10 do			mt[i][j] = i * j		end	endendfunction print_mt()	for i = 1, table.getn(mt) do		for j, v in ipairs(mt[i]) do			print(i, j, v)		end	endendcreate_mt()print_mt()--可变参数function add(...)	local s = 0	for i, v in ipairs{...} do		s = s + v	end	return sendprint(add(1,2,3))--元表my_meta={	__add=function(op1, op2)		op = {}		op.x = op1.x + op2.x;		op.y = op1.y + op2.y;		return op	end}a={x=1, y=2}setmetatable(a,my_meta)b={x=3,y=4}c=a+bprint(c.x,c.y)--输出4,6