clone an associative array?

clone an associative array?

[Marc Chantreux]

hello all,

i don't know what i missed in 'parameters expansions' manual but i'm
unable to clone an associative array :

% typeset -A homemade
% homemade=( tm myself c 2005 )
% echo $homemade[tm]
myself

% typeset -A counterfeit
% counterfeit=${homemade}

% echo $counterfeit[c]
m

% counterfeit="${homemade}"
% echo $counterfeit[c]
m

% counterfeit="${(AA)homemade}"
% echo $counterfeit[c]
m

% counterfeit="${(A)homemade}"
% echo $counterfeit[c]
m

# other tries failed too ...

in a future time, i would like to write something as :

func () {
    local who=$1
    shift
    local -A config
    config=$@

    # implementation here ....

}

i'm sure that it is possible, i just want to know how.

regards
mc

Re: clone an associative array?

[Peter Stephenson]

Marc Chantreux wrote:
> hello all,
> 
> i don't know what i missed in 'parameters expansions' manual but i'm
> unable to clone an associative array :
> 
> % typeset -A homemade
> % homemade=( tm myself c 2005 )
> % echo $homemade[tm]
> myself
> 
> % typeset -A counterfeit
> % counterfeit=${homemade}

As it's a sort of array, you need braces.  However, you also need
to copy keys as well as values.  The syntax is:

typeset -A counterfeit
counterfeit=(${(kv)homemade})

Make sure you don't have the option SH_WORD_SPLIT set.  (This is a
classic example of why it's a good idea to get used to doing without it.)

-- 
Peter Stephenson <pws@csr.com>                  Software Engineer
CSR PLC, Churchill House, Cambridge Business Park, Cowley Road
Cambridge, CB4 0WZ, UK                          Tel: +44 (0)1223 692070




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Re: clone an associative array?

[Stephane Chazelas]

On Fri, Aug 19, 2005 at 04:13:38PM +0200, Marc Chantreux wrote:
[...]
> % typeset -A counterfeit
> % counterfeit=${homemade}
[...]

counterfeit=("${(@kv)homemade}")

-- 
Stephane

Re: clone an associative array?

[Peter Stephenson]

Peter Stephenson wrote:
> > % typeset -A counterfeit
> > % counterfeit=${homemade}
> 
> As it's a sort of array, you need braces.

I meant parentheses, of course.  You've already got the braces.

> typeset -A counterfeit
> counterfeit=(${(kv)homemade})
> 
> Make sure you don't have the option SH_WORD_SPLIT set.  (This is a
> classic example of why it's a good idea to get used to doing without it.)

This is what Stephane's version works around.

pws


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Re: clone an associative array?

[Stephane Chazelas]

On Fri, Aug 19, 2005 at 03:24:52PM +0100, Peter Stephenson wrote:
[...]
> typeset -A counterfeit
> counterfeit=(${(kv)homemade})
> 
> Make sure you don't have the option SH_WORD_SPLIT set.  (This is a
> classic example of why it's a good idea to get used to doing without it.)
[...]

Hmmm,

~$ typeset -A a b
~$ a=(a 1 b '' c 2)
~$ echo "$a[b]"

~$ b=(${(kv)a})
zsh: bad set of key/value pairs for associative array

Hence, the b=("${(@kv)a}") that would also work with
SH_WORD_SPLIT.

-- 
Stephane