Re: new "empty" value/type in Lua?

[Petite Abeille <petite.abeille@...>]

On Jul 1, 2013, at 8:04 PM, Roberto Ierusalimschy <roberto@inf.puc-rio.br> wrote:

>> Couldn't a lot of ambiguity and unexpected behavior avoided by keeping
>> nil but introducing two new functions to the table library called
>> "table.has(t,key)" and "table.delete(t,key,[to])" - and dropping the
>> deletion via assigning nil?
> 
> At last something new and worth a discussion. Does anyone see problems/
> incompatibilities/etc. with this?

I, for one, find this an unnecessary and taxing complication, pandering to a minority taste.

Unnecessarily because, if one care enough about it, one can use placeholders and/or metamethods to shape a table whichever way one sees fit.
Taxing because, under such a schema, what used to be a primitive, immediate table operation ( t[ k ] = nil ) has become an esoteric, indirect library operation ( table.delete( t, k ) ).
Minority taste because, while not beyond useful every now and then, it's not worth the overall quotidian complications.

A bit of the perfect (full fledge nil support) being the enemy of the good (primitive key removal).

Just my 2¢.