Re: case $var in $list) issue

[Chet Ramey]

On 11/1/24 7:15 AM, Greg Wooledge wrote:
> On Fri, Nov 01, 2024 at 06:00:49 +0100, #!microsuxx wrote:
> > shopt -s extglob
> > m='@(a|b)' ; case b in $m) echo ye ; esac
> > ye
>
> Huh, interesting indeed.

It's really not.


> hobbit:~$ shopt -s extglob
> hobbit:~$ m='a|b'
> hobbit:~$ case b in $m) echo ye ; esac
> hobbit:~$ m='@(a|b)'
> hobbit:~$ case b in $m) echo ye ; esac
> ye
>
> I can only speculate that it sometimes re-parses the contents of $m
> based on the first character.

The case statement has a pattern list with a single element, $m, which
expands to a single unquoted extglob pattern, @(a|b).

The case statement tries to match b against that pattern, and, since
extglob is enabled, it matches.

--
``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/

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