Re: typeof() creates elements in an array

[Andrew J. Schorr]

On Mon, Sep 27, 2021 at 08:44:05PM -1000, david kerns wrote:
> Not a bug
> 
> Remove the typeof operator and you’ll see the array is still increased. 
> Referencing the new element increases the length
> 

Agreed.

> > On Sep 27, 2021, at 11:13 AM, Ivo Palli <ivo@palli.nl> wrote:
> >> Normally, passing a variable that has never been used to a built-in
> >> function causes it to become a scalar variable (unassigned). However,
> >> isarray() and typeof() are different; they do not change their arguments
> >> from untyped to unassigned.

Here's what looks like a more interesting question to me regarding
this issue.

bash-4.2$ ./gawk 'BEGIN {print typeof(x); x[0] = 0; print typeof(x)}'
untyped
array

bash-4.2$ ./gawk 'BEGIN {print typeof(x[0]); x[0][0] = 0; print typeof(x[0])}'
unassigned
gawk: cmd. line:1: fatal: attempt to use scalar `x["0"]' as an array

This example does seem to be more at odds with the language in the manual,
since the array element here has been created as a unassigned scalar, not
as an untyped value. I don't know whether that can be avoided. The array
instantiation stuff is tricky.

Regards,
Andy