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James Graves <> writes:

> 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.)

Not a good idea since the transition between floats and integers is
fluid: the larger a value gets, the more likely a non-integer will get
rounded to an integer by accident.  3.14159265 is a noninteger, but
54325432543254325432543254325433.14159265 is likely an integer.

So I'd recommend just allowing for numeric keys <=0 as not affecting #
of the table.

David Kastrup