Re: Feature request: index of index

[Phi Debian]

Meanwhile you may use functions to setup your variables something along
those lines.

PW$ function first-index { echo $1; }
PW$ function last-index { shift $(($#-1)) ; echo $1; }

PW$ declare -a array=([5]="hello" [11]="world" [42]="here")
PW$ declare -i first_index=$(first-index ${!array[@]})
PW$ declare -i last_index=$(last-index ${!array[@]})

PW$ echo $first_index $last_index
5 42

On Thu, May 6, 2021 at 1:24 PM Léa Gris <lea.gris@noiraude.net> wrote:

> Currently, to know the index of an array's indexes (example: first or
> last index), it needs an intermediary index array:
>
> > #!/usr/bin/env bash
> >
> > declare -a array=([5]=hello [11]=world [42]=here)
> > declare -ai indexes=("${!array[@]}")
> > declare -i first_index=${indexes[*]:0:1}
> > declare -i last_index=${indexes[*]: -1:1}
> > declare -p array indexes first_index last_index
>
> Which prints:
> > declare -a array=([5]="hello" [11]="world" [42]="here")
> > declare -ai indexes=([0]="5" [1]="11" [2]="42")
> > declare -i first_index="5"
> > declare -i last_index="42"
>
> It would be convenient to be able to index directly with this syntax:
>
> declare -i first_index=${!array[@]:0:1}
> declare -i last_index=${!array{@}: -1:1}
>
>
> --
> Léa Gris
>
>
>