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

[alex xmb sw ratchev]

ah
probably to use quotes ..

On Sun, Feb 18, 2024, 15:01 alex xmb sw ratchev <fxmbsw7@gmail.com> wrote:

>
>
> On Sun, Feb 18, 2024, 14:51 Kerin Millar <kfm@plushkava.net> wrote:
>
>> On Sun, 18 Feb 2024 14:34:43 +0100
>> alex xmb sw ratchev <fxmbsw7@gmail.com> wrote:
>>
>> > On Sun, Feb 18, 2024, 14:18 Kerin Millar <kfm@plushkava.net> wrote:
>> >
>> > > On Sat, 17 Feb 2024 17:01:13 +0100
>> > > alex xmb sw ratchev <fxmbsw7@gmail.com> wrote:
>> > >
>> > > > oh i know why it failed
>> > > > set interprets the first -- away
>> > >
>> > > That is not why it is failing to behave as you expect. Rather, the
>> issue
>> > > is that your conditional expression is incorrect. It should be [[
>> "$f$*$f"
>> > > == *"$f--$f"* ]]. Note that you have chosen to change the value of
>> IFS. It
>> > > is important that you do not omit the quotes - not even for the left
>> hand
>> > > side of the expression!
>> > >
>> >
>> > i thought there is a ' flat left side of == '
>>
>> Unfortunately, the raw output of xtrace is not much use for human
>> eyeballs. Here's the exact difference.
>>
>> $ ( set aa bb cc -- dd; f=$'\1' IFS=$f PS4= BASH_XTRACEFD=1; set -x; [[
>> "$f$*$f" == *"$f--$f"* ]] ) | hexdump -C
>> 00000000  5b 5b 20 01 61 61 01 62  62 01 63 63 01 2d 2d 01  |[[
>> .aa.bb.cc.--.|
>> 00000010  64 64 01 20 3d 3d 20 2a  01 5c 2d 5c 2d 01 2a 20  |dd. ==
>> *.\-\-.* |
>> 00000020  5d 5d 0a                                          |]].|
>>
>> $ ( set aa bb cc -- dd; f=$'\1' IFS=$f PS4= BASH_XTRACEFD=1; set -x; [[
>> $f$*$f == *"$f--$f"* ]] ) | hexdump -C
>> 00000000  5b 5b 20 61 61 62 62 63  63 2d 2d 64 64 20 3d 3d  |[[
>> aabbcc--dd ==|
>> 00000010  20 2a 01 5c 2d 5c 2d 01  2a 20 5d 5d 0a           | *.\-\-.*
>> ]].|
>>
>> Of course, you needed the asterisk characters in the pattern too.
>>
>
> ah ye =p unfinished inhead code
>
> question , what should these hexdumps show
>
> --
>> Kerin Millar
>>
>