[ILUG] dynamic variable creation in sh

[A. Dreyer]

On Tue, 05 May 2009, Gavin McCullagh wrote:

> Hi,
> 
> On Tue, 05 May 2009, ageerts at agc-it.com wrote:
> 
> > $ a="example" 
> > $ eval "${a}_desc"=\"hello world\" 
> > $ echo "$example_desc" 
> 
> I wasn't as clear as I should have been, sorry.  That bit, I can do.
> Effectively the same as:
> 
> VAR_1="I"
> VAR_2="pity"
> VAR_3="the"
> VAR_4="fool."
> ...
> 
> Now what I want to do is loop over the values until "VAR$i" is not set, eg
> concatenating them together.
> 
> i=1
> eval CURRVAL="VAR_${i}"
> while [ ! -z $CURRVAL ]
> do
>       VALUES ="$VALUES : $CURRVAL"
>       eval CURRVAL="VAR_${i}"
>       i=$(( $i + 1 ))
> done
> 
> but that doesn't work.
> 
> Gavin

Hi Gavin,

To many little mistakes... 

Try this one:
--snip--
#!/bin/sh -fe

VAR_1='I'
VAR_2='pity'
VAR_3='the'
VAR_4='fool.'
i=1
eval "CURRVAL=\${VAR_$i}"
VALUES=''
while [ ! -z $CURRVAL ]; do
	VALUES="$VALUES : $CURRVAL"
	i=`expr $i + 1`
	eval "CURRVAL=\${VAR_$i}"
done
echo "$VALUES"
--snip--


Cheers,
Achim

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Achim Dreyer                || http://www.adreyer.com/
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