Re: case $var in $list) issue

[#!microsuxx]

On Fri, Nov 1, 2024, 16:51 Greg Wooledge <greg@wooledge.org> wrote:

> On Fri, Nov 01, 2024 at 11:20:31 -0400, Zachary Santer wrote:
> > On Thu, Oct 31, 2024 at 9:55 PM #!microsuxx <fxmbsw7@gmail.com> wrote:
> > >
> > > ~ $ echo $short
> > > li|la|ds|fs|ac|U|S|u|s|r|i|f|c
> >
> > declare -a short=( li la ds fs ac U S u s r i f c )
> > match='false'
> > for pattern in "${short[@]}"; do
> >   if [[ ${whatever} == ${pattern} ]]; then
> >     match='true'
> >     break
> >   fi
> > done
> >
> > Probably the way to go if your list of patterns is determined
> dynamically.
>
> Yeah, but in my experience, a lot of people just *abhor* writing a loop.
> They'll do anything else.  It's like a religion or something.
>
> (Also, you should quote "$pattern" there if each list element is to be
> treated as a fixed string instead of a glob.)
>
> > If the case construct didn't require a | between different patterns in
> > the same pattern list, then you could just expand ${short[@]} there.
>
> We've already learned that you can use an extglob to achieve the desired
> result (matching a short string against a list of short strings in a
> single matching step).  Chet even explained why it works.


imo long complecated shall work too

but i failed at that :

a=( "' " '$(' ) IFS=\| m='@('${a[*]@Q}\) IFS=$' \t\n'

for : case '$(' in $m) echo ye ;; esac

but

~ $ echo $m
'|'$(')

what is this $m
i dont get it

its supposed to Q escape both elements in a[*] with one | inside separating

.. ?

greets

> > ~ $ echo $short
> > > li|la|ds|fs|ac|U|S|u|s|r|i|f|c
>
> shopt -s extglob
> shorts="@($short)"
> case $input in $shorts) echo match;; *) echo no match;; esac
>     ... or the [[ ]] equivalent.
>
> > Using [[  ]] in a for loop is going to be easier to wrap your head
> > around
>
> I'm assuming that writing a simple script that works, is efficient, and
> is readable is NOT the goal here.  It very rarely is.
>
> The goal is most likely one of:
>
>  * Do it using a special dedicated feature that looks cool.
>  * Do it in a clever way instead of an obvious way.
>  * Make it short.
>
> We do get the golfer mentality sometimes, though I don't think xmb falls
> into that particular group.  Usually it's one of the first two.
>
>