为什么a不正确？local a = true print(a and false or true) 为什么结果总是true，无论a是false还是true？

为什么a不正确？ 我不理解。

代码：

C:\Users\Administrator>lua53
Lua 5.3.4  版权所有 (C) 1994-2017 Lua.org, PUC-Rio
> local a = true print(a and false or true)
true
> local a = false print(a and false or true)
true
> local a = false print(a == true and false or true)
true
> local a = true print(a == true and false or true)
true
> local a = true print(a == false and false or true)
true
> local a = false print(a == false and false or true)
true
> local a = false print((a == false) and false or true)
true
> local a = false print(not a )
true
> local a = true print(not a )
false
>