Re: [ANN] Lua 5.2.0 (alpha) now available

[Enrico Colombini <erix@...>]

A minimalist crazy idea: perhaps, just to avoid surprises and offer a 
predictable behavior to Lua beginners, #t could return nil if the list 
has holes (i.e. it's not a proper array).

That should be cheap to implement, at least for one-way behavior: once a 
hole in introduced (i.e. a non-nil assignment is made outside the range 
[1..#t+1], or a nil assigment is made inside [1..#t-1]) #t would stay 
nil forever even if the hole is later filled. It would probably cost too 
much to detect if all holes are re-filled.

I'm not sure if the that behavior could create trouble in normal usage, 
though (e.g. because of a temporary nil assignment inside the array).

--
  Enrico