On Sun, Jan 14, 2024 at 4:03 PM Ray Andrews <rayandrews@xxxxxxxxxxx> wrote:When assigning to an associative array ... % typeset -A asc=( $something ) ... the expansion of $something has to yield an even number of "words", yes. But remember the previous lesson about those outer parens -- they only mean that the thing to the left is an array, they don't matter to what's inside those parens. So if $something is an array with empty elements, those elements are going to be elided, which might leave you with an odd number of words and break the assignment -- or possibly worse, turn some values into keys and some keys into values.
Exactly as I understand it. A arrays are 'not very clever' --
they don't try to protect you from yourself, there's no internal
place holding for a missing value, and as you say things must be
kept to pairs.
I've noticed that. One might think that the order of assignment would be 'the order' by inevitability, but that seems not to be the case. I don't understand how it could be otherwise but nevermind.(output may vary because associative arrays are not ordered).
Returning to the original example, that means if you're copying one
associative array to another, you need to copy both the keys and the
values, and quote it:
% typeset -A asc=( "${(@kv)otherasc}" )
You said something the other day that was important: the parens
do not say 'I am an array' they say 'turn me into an array' it's
one of those things that must be clear.
Yeah, I'm getting somewhat
competent with A's. They're not very forgiving but the rules
aren't that hard to remember.