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1. Unexpected behavior with "not not" (score: 386)

Author: "Aaron Brown" <aaron-lua@...>

Date: Thu, 30 Jun 2005 13:08:04 -0400

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

2. Re: Unexpected behavior with "not not" (score: 386)

Author: Wim Couwenberg <w.couwenberg@...>

Date: Thu, 30 Jun 2005 19:47:37 +0200

That's funny! The reason seems to lie in some tiny optimisations in lcode.c (that's in 5.0.2): The compiler makes the following substitutions if nil, false or true are encountered as *constants*: no

3. Re: Unexpected behavior with "not not" (score: 386)

Author: Rici Lake <lua@...>

Date: Thu, 30 Jun 2005 23:15:06 -0500

The compiler makes the following substitutions if nil, false or true are encountered as *constants*: not nil --> true not false --> true not true --> false so "not not nil" is directly emitted as "f

4. Re: Unexpected behavior with "not not" (score: 386)

Author: "Aaron Brown" <aaron-lua@...>

Date: Fri, 1 Jul 2005 09:07:57 -0400

I definitely read that sentence in the reference manual multiple times to make sure I wasn't missing something. I can imagine writing a function and wanting it to hide internal information; maybe the