Re: Use of $@

[Christof Warlich]

Am 21.02.23 um 23:48 schrieb Chet Ramey:
> "${!@}" is not a useful expansion. It ends up being indirect expansion,
> since it's not defined to do anything else, and "$@" in a context where
> word splitting doesn't take place rarely expands to a usable variable
> name.
Yes, I got that :-).
> It is not equivalent to ${!1} ${!2} ... .

I would have assumes it to iterate over the indices of "$@", in the same
way as for the array a=(hi ho), ${!a[@]} iterates over the indices of
"${a[@]}":

$ a=(hi ho)
$ for i in "${!a[@]}"; do echo $i; done
0
1

... but (to me, unexpectedly) the following does not work:

$ a=(hi ho)
$ f() for i in "${!@}"; do echo $i; done
$ f "${a[@]}"
bash: hi ho: invalid variable name

Wouldn' it make sense to make "${!a[@}" and "${!@}" behave similar in
some future version of bash?