Re: Get cursor position (Was: [bug report] prompt can erase messages written on the terminal by background processes)

[Mikael Magnusson <mikachu@xxxxxxxxx>]

On 12/8/22, Stephane Chazelas <stephane@xxxxxxxxxxxx> wrote:
> 2022-12-08 09:34:41 +0100, Roman Perepelitsa:
> [...]
>> > curpos() {
>> >   set -o localoptions -o extendedglob
>> >   local match answer
>> >   IFS= read -rsdR -t0.2 answer$'?\e[6n' &&
>> >     [[ $answer = (#b)$'\e['(<->)';'(<->) ]] &&
>> >     eval "${1-x}=\$match[2] ${2-y}=\$match[1]"
>> > }
>>
>> Functions that accept output parameter names as arguments are tricky.
>> The following won't work:
>>
>>     # Which line is the cursor on?
>>     curpos _ answer
>>     print -r -- "The cursor is on the line number $answer"
> [...]
>
> Yes, I thought of using 3 as the intermediary variable, but
> decided against it as we can't do anything about match,
> mbegin... anyway.
>
> typeset -g "${1-x}=$match[2]" "${2-y}=$match[1]"
>
> Doesn't work either. I guess there's no way to access variables
> by the same name in that parent scope or to unlocal a variable?

I have a patch for it, but I never sent it because I couldn't think of
a usecase. http://comm.it.cx/cgit/zsh-cvs/patch/?id=cf1ba693c9f3ed80ff085bfed74d854796349a0d
(I'm not 100% sure all the error checks are correct, and cover all
cases, especially wrt bart's private module).

-- 
Mikael Magnusson