Re: Error on arithmetic evaluation of `~0`.

[Andreas Schwab]

On Dez 20 2018, Greg Wooledge <wooledg@eeg.ccf.org> wrote:

> The issue you're reporting appears to be present in arithmetic contexts
> in general, not only arrays:
>
> wooledg:~$ echo $((~0))
> bash: /home/wooledg: syntax error: operand expected (error token is 
> "/home/wooledg")

This has been fixed in bash 5.0.

> It appears that bash is performing tilde expansion when there's no
> whitespace in front of the tilde, or bitwise negation if there is
> whitespace.

POSIX says that arithmetic expressions are not subject to tilde
expansion.  IMHO bash shouldn't do that either for indexed array
subscripts, since they are arithmetic expressions.

Andreas.

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
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