Re: Associative Arrays

[Nikolai Weibull <zsh-users-list@pcppopper.org>]

* Stephane Chazelas <Stephane.Chazelas@morse.com> [Oct 21, 2004 13:10]:
> > I'm have a few questions regarding associative arrays.  What exactly is
> > the A flag for parameter expansion for?  I mean, how does one use it,
> > and how does one use the AA flag?
>
> Not very useful, except maybe to avoid the use of typeset.
>
> typeset -A a
> a=(foo bar)
>
> can be written:
>
> : ${(AA)=a::=foo bar}

aha, OK.  How very useful.

> > Is there any way to pass an associative array as ONE argument to a
> > function and easily deal with it as the same associative array in the
> > other function?  The easiest way seems to be the "pass-by-reference"
> > technique, where one simply passes the name of the array and then use
> > the P flag to deal with it.

> You could use "${${(@qqkv)A}[*]}"
> $ typeset -A A
> $ A=("foo" "b bar" \' \" "" q)
> $ print -lr "${${(@qqkv)A}[*]}"
> '' 'q' 'foo' 'b bar' ''\''' '"'

> So that in the function you can have
>
> typeset -A local_hash
> eval "local_hash=($1)"
>
> or:
>
> typeset -A local_hash
> local_hash=("${(Q@)${(z)1}}")

Aha, double quotation and then dequoting.  What a bitch...is this
seriously the simplest/only ways to do it?  I'd say that shell
programming would be a lot simpler as a whole if this was simpler.
Still, I guess I'm thinking a bit too much like a Ruby or C programmer.
	nikolai

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