Re: Lua 5.2 sequence definition - clarification needed

[Lorenzo Donati <lorenzodonatibz@...>]

On 29/06/2011 17.27, James Graves wrote:
> I would re-write that section as follows:
>
> Unless the __len metamethod is set, the length N is defined for a
> table which contains consecutive, positive integer keys from 1 to N
> and does not contain any positive integer keys outside the range 1 to
> N.  Such a table is said to contain a 'proper sequence'.
>
> The following types of keys do not affect the length of the table and
> whether or not it contains a proper sequence:
>
> 0 (zero)
> negative integer (-1, -2, -55, etc.)
> non-integer (-1.3, 3.14159265, etc.)

Really? I don't know the internals of Lua, but I thought positive 
numbers, even non-integer ones, could make the table a non-sequence.

From the current definition it seems so, anyway. I.e.: a table is a 
sequence if its positive numeric keys (non necessarily the integer ones) 
*are* 1,2...,n (not *contains*).

I find the current definition much clearer IMHO (save for the glitches I 
mentioned in the other post)

> other non-numeric (strings, tables, functions, etc.)
>
> James Graves

cheers
-- Lorenzo