Mac lua tutorial - 1 (Hello world)

Macbook pro (OS X EI Captian 10.11.5)
lua-5.3.3-0.pkg 2016-06-06 0.43
1. lua Hello world
1.1 準備 luaHello.lua
-- luaHello.lua
-- lua -E luaHello.lua
print ("Hello World!")
1.2 執行 (@bash) lua -E luaHello.lua

2. lua function
2.1 準備檔案
-- luaFunction.lua
-- lua -E luaFunction.lua
foo = function () print("hello") end -- declare the function

foo() -- call the function
2.2 執行

3. lua IO

3.1 準備檔案
-- luaIO.lua
-- lua -E luaIO.lua
print ("enter a integer for n ")
n=io.read("*n") --not *number
if  (n<0)   then return 1 end

sum = 0
i = 1 --0 has no effect :)?
while (i<=n) do
    sum = sum + i^2
    i = i + 1
end

print(sum)
3.2 執行