Re: why fail , [[ $sep$*$sep == $sep--$sep ]]

[Chet Ramey]

On 2/17/24 10:07 AM, alex xmb sw ratchev wrote:
> i was trying and epic failed
>
> set aa bb cc -- dd ; f=$'\1' IFS=$f ; [[ $f$*$f == "$f--$f" ]] && echo ye
>
> it says no ye

It looks like you've found a bug that manifests itself under a very
specific set of circumstances: IFS=$'\1', word splitting not performed,
and an unquoted word. Bash doesn't quote the ^A sufficiently, and since
it uses ^A as an internal quote character, removes it. This causes the
match to fail. There are other places this happens: case commands, shell
pattern expansion, and array subscript expansion.

I pushed a fix for it this morning; there is another change in the
pipeline.

Chet

--
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU    chet@case.edu    http://tiswww.cwru.edu/~chet/