Re: Keying arrays to names: is there an array of arrays?

[Bart Schaefer <schaefer@xxxxxxxxxxxxxxxx>]

On May 28,  2:34am, Johann 'Myrkraverk' Oskarsson wrote:
>
> The following version also works with IFS="" (I guess it will work
> with IFS equal to something sensible too).
> 
> mapassign() {
>     local h=$1 k=$2 
>     shift 2 
>     set -- ${(j: :q)*} 
>     typeset -gA $h 
>     typeset -g $h\[$k\]="$*"
> }

A better approach might be:

    mapassign() {
        emulate -L zsh
	local h=$1 k=$2 IFS=$' \t\n\0'
	shift 2
	set -- ${(q)*}
	typeset -gA $h
	typeset -g $h\[$k\]="$*"
    }
 
> Same with this one:
> 
> mapread() {
>     set -- $1\[$2\]
>     reply=( ${(s: :Q)${(z)${(P)1}}} ) 
> }

That's actually incorrect.  The (z) option is already splitting the
value; you shouldn't need or want to split it again with (s: :).  If
the setting of IFS is preventing (z) from working properly, that's
probably a bug, but in any case the workaround is to make IFS local.

    mapread() {
	emulate -L zsh
	local IFS=$' \t\n\0'
	set -- $1\[$2\]
	reply=( ${(Q)${(z)${(P)1}}} )
    }

If you're going to use these functions for hash access anyway, then
you might as well also use ${(q)2} instead of $2 in both of them, to
avoid issues with non-alphanumeric keys.