In praise of 'nil' (Was: Proposal for table length operator

[Dirk Laurie <dpl@...>]

On Wed, Dec 15, 2010 at 06:28:30AM +0200, Mark Hamburg wrote:
> True. I guess it's more the issue that Lua has a number of more 
> or less standard idioms that almost work until confronted with nil 
> and so you can write idiomatic code that will be fine until you hit 
> the case it doesn't handle and that doesn't generally get called out 
> as not handled in descriptions of the idiom.

It is a tribute to the thoughtfulness with which the behaviour of nil 
has been designed that very often one does not need to test for it.
It is a beautiful philosophical concept.
    What happened before the Big Bang?  Nil.

And nobody, really nobody, stops you from writing
    if a==nil then
when you can't think of a more elegant (but probably more
obfuscated) way to do what you mean.

Dirk