Re: Iteration and nils

["Chris Swetenham" <cswetenham@...>]

> A sensible (IMHO) remedy has already been suggested a few times: there
> should something *officially sanctioned* that means "I have a value
> without actually having a value". Call it table.hole, call it sonofnil,
> call it null (the latter had to be reserved words), call it what you
> will: I think once such a "value" is a standard feature of Lua and used
> correctly as such, many problems connected with nil will simply go away.

If I am not mistaken, JavaScript has both "null" and "undefined" values; 
"undefined" has the same role as "nil" does in Lua, and "null" has the 
meaning you suggest. It seems to me that introducing a new "null" value as 
you suggest would be an elegant way of solving the problems of "nil" without 
introducing any new ones, with the only small drawback that "null" becomes a 
reserved word.

It would be possible to simulate by simply adding "null = {}" somewhere, but 
then this would evaluate to "true" in a boolean context, so I think it would 
be best if it were added to the base language.

Chris Swetenham