Re: How can one decide between 'not set' and 'not existing?

[Dimiter 'malkia' Stanev <malkia@...>]

On 7/25/2012 8:30 PM, Coda Highland wrote:
> On Wed, Jul 25, 2012 at 9:46 PM, Jay Carlson <nop@nop.com> wrote:
> > On Jul 25, 2012, at 5:09 PM, Coda Highland wrote:
> >
> > > On Wed, Jul 25, 2012 at 2:02 PM, Dimiter 'malkia' Stanev
> > > <malkia@gmail.com> wrote:
> > > > -- "function() end" would gurantee an unique value, differentiated from
> > > > others, unless the VM merges it under one umbrella. Even them, maybe reusing
> > > > coroutine might return you an unique value for the lifetime of the
> > > > application (or something even simpler)
> > >
> > > Unless I miss my guess, the VM couldn't merge it because they'd have
> > > different upvalues.
> >
> > There are no free variables in function() end and hence no upvalues, so it certainly could be merged/hoisted to chunk level.
>
> Oh right. Silly me.

Put me in the silly list too :)

After seeing it done much simpler ...

> > Use NULL={} instead. List constructors guarantee uniqueness.

HERE :)

> *nods* And tables have reference equality only, so that's completely sufficient.
>
> /s/ Adam