foreach loop through associative array in bash only returns last element

Question

This should print the whole associative array to the console:

#!/bin/sh

declare -a array=([key1]='value1' [key2]='value2')

for key in ${!array[@]}; do
    echo "Key = $key"
    echo "Value = ${array[$key]}"
done

echo ${array[key1]}
echo ${array[key2]}

Instead it prints oly the last variable:

[mles@sagnix etl-i_test]$ ./test.sh 
Key = 0
Value = value2
value2
value2

Where is my fault?

@htor: Bash Version is 3.2.25(1)-release.

Take a look at http://stackoverflow.com/q/688849/1983854 , there are many solutions to this. — fedorqui, May 22 '13 at 09:49
are you sure /bin/sh is actually /bin/bash? also associative arrays are built using `-A` not `-a` ... see answer below — Ahmed Masud, May 22 '13 at 09:51
What's your BASH version? Provide the output of `echo $BASH_VERSION` in your question. — , May 22 '13 at 12:58

score 6 · Accepted Answer · answered May 22 '13 at 13:08

Associative arrays are supported in Bash 4 and newer versions. An array declared with the -a option is just a regular array that can be indexed by integers, not keys. This declaration results in the array with one element value2. When iterating over the keys with for key in ${!array[@]} the value of $key is 0 and therefore you get the first element.

Given the error output you get when trying to use -A to declare to array, I assume your Bash version is older than 4. Inspect the variable $BASH_VERSION.

For a deeper explaination of arrays, see http://mywiki.wooledge.org/BashGuide/Arrays.

score 3 · Answer 2 · answered May 22 '13 at 09:56

3

#!/bin/bash

declare -A array=([key1]='value1' [key2]='value2')

for key in ${!array[@]}; do
    echo "array[$key] = ${array[$key]}"
done

echo ${array[key1]}
echo ${array[key2]}

answered May 22 '13 at 09:56

Ahmed Masud

21,655
3
33
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that gives me an error `./test.sh: line 3: declare: -A: invalid option declare: usage: declare [-afFirtx] [-p] [name[=value] ...]` – mles May 22 '13 at 12:26
1

@mles: you aren't using `bash` 4 or later. – chepner May 22 '13 at 13:17

foreach loop through associative array in bash only returns last element

2 Answers2