It appears that you need the “p” flag for the join and probably for the split as well.

Also, @ says “In  double  quotes,  array  elements  are put into separate words.”
But you don’t have double quotes so the @ isn’t needed.

> % var1=( a b c d )   
> % var2=${(j:\0:)var1}
> % print $#var2
> 10

At this point var2 is a scaler with two characters ‘\’ and ‘0’ separating what were the words.

> % var3=${(pj:\0:)var1}
> % print $#var3
> 7

This is what you are expecting / needing

> % print -l ${(0)var3}
> a
> b
> c
> d

The print works

> % print -l ${(@0)var3}
> a
> b
> c
> d


The @ isn’t needed

(Again… I’m new here so please verify everything)

> On Nov 27, 2019, at 8:18 AM, Marc Chantreux <eiro@phear.org> wrote:
> 
> hello Perry,
> 
>> I’m very new here so take what I say with caution but why
>> did you put the backslash before the 0?
> 
> if you use xxd:
> 
>    echo -n 0 $'\0'|xxd
> 
> you can see that 0 is the symbol 0x30 (48th of the ascii table)
> when \0 is 00.
> 
> \0 is non-sense in a legit text stream so it can be used as
> a separator instead of all those separators that can exist in
> text ( "\n", ",", ":" " ", "\t").
> 
> see xargs -0, find -print0, ...
> 
> regards
> marc
> 
>