Re: code not working ..

[alex xmb sw ratchev]

On Wed, Sep 11, 2024, 1:52 AM Greg Wooledge <greg@wooledge.org> wrote:

> On Wed, Sep 11, 2024 at 01:35:15 +0200, alex xmb sw ratchev wrote:
> > hmm hard to code an args check like this ..
>
> Are you trying to determine whether a STRING argument appears in a LIST?
>
> I have a feeling that's what you're trying to do.
>
> Many people think there should be some "clever" way to do this using
> list-to-string serialization and delimiters.
>
> The actual BEST way to do it is to iterate over the list, do a simple
> comparison of your string against each list element, and stop if you
> have a match.
>
> Loops are not evil.  Loops are your friend.  You don't need to do
> backflips trying to avoid writing them.
>
>
> # Usage: isin stringvarname arrayvarname
> # Returns 0 (true) if the string pointed to by stringvarname appears
> # as an element of the array pointed to by arrayvarname.  Otherwise,
> # returns 1.
>
> isin() {
>     local -n _isin_needle="$1"      # Using namerefs means we must
>     local -n _isin_haystack="$2"    # use ridiculous local variable names
>     local _isin_x                   # to try to avoid collisions.
>
>     for _isin_x in "${_isin_haystack[@]}"; do
>         [[ $_isin_needle = "$_isin_x" ]] && return 0
>     done
>     return 1
> }
>
>
> hobbit:~$ var=foo
> hobbit:~$ arr=(a 12 foo bar)
> hobbit:~$ isin var arr ; echo "$?"
> 0
> hobbit:~$ var=fo
> hobbit:~$ isin var arr ; echo "$?"
> 1
>
>
> Of course, this function could be written in many other ways.  You might
> choose to pass the first argument as a value, rather than a variable
> name that must be dereferenced.  You might expand the array in the caller,
> and pass each array element as an additional argument.  These are all
> reasonable choices.
>
> What's *not* as reasonable is trying to join the array into a string with
> a weird delimiter like $'\xff' before, between and after every element,
> and then match that string against a pattern like *$'\ff'"$string"$'\ff'*.
> I wish people would stop doing that.  I know they won't, but I can dream.
>

at least u answered and helped some ..
yes i check script args via this
the 'new' this time is the substitution of inside var seps , .. as anyway
for this check not needed
.. i dont expect it to fail ..

btw , unlike ur old sticking to old methods , i blaze the newest ..
learning ...
greets ..

>