Re: whats wrong with (( a = 8 , a > 4 && a -= 2 || a-- )) , bash: ((: a = 8 , a > 4 && a -= 2 || a-- : attempted assignment to non-variable (error token is "-= 2 || a-- ")

[Bipul kumar]

Hi Alex,

It's failing because, what you are doing is compound assignment
  a -= 2
which needs to be inside parentheses.
It works for me.
 (( a = 8 , a > 4 && (a -= 2) || a-- ))
$ echo $a
6

source https://www.gnu.org/software/bash/manual/bash.html    search
"compound assignment"

    Respectfully,
    Bipul
    PUBLIC KEY <http://ix.io/1nWf>
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On Thu, Mar 23, 2023 at 4:03 PM alex xmb ratchev <fxmbsw7@gmail.com> wrote:

> i remember doing && (( code
> maybe i didnt '=' in action there
>
> (( a = 8 , a > 4 && a -= 2 || a-- ))
>
> bash: ((: a = 8 , a > 4 && a -= 2 || a-- : attempted assignment to
> non-variable (error token is "-= 2 || a-- ")
>
>
> (( a = 8 , a > 4 && a-- && a-- || a-- ))
>
> works
> a=6
>
> ..
> i suppose this is a (( lex bug where u didnt include || && in op for =
>
> is it ? :))
>
> greets
>