Unexpected behavior with "not not"

["Aaron Brown" <aaron-lua@...>]

Hey everybody,

The third and fourth of the following lines don't seem right
to me.  Do I have a faulty concept in my head?

print(not not nil)              --> false
print(not not nil and true)     --> false
print(not not (nil and true))   --> nil (!)
print(not (not (nil and true))) --> nil (!)

To take the fourth line as an example, I expect it to
evaluate like this:

* not (not (nil and true))
* not (not nil) -- innermost first
* not true
* false

(I get the same results on several versions of Lua.)

-- 
Aaron