I want to access the array index variable while looping thru an array in my bash shell script.
myscript.sh#!/bin/bash
AR=('foo' 'bar' 'baz' 'bat')
for i in ${AR[*]}; do
echo $i
done
The result of the above script is:
foo
bar
baz
bat
The result I seek is:
0
1
2
3
How do I alter my script to achieve this?
Add one character:
#!/bin/bash
AR=('foo' 'bar' 'baz' 'bat')
for i in ${!AR[*]}; do ←
echo "$i"
done
(Add an exclamation mark (!) to the array expansion:
${!AR[*]}.) From the man page:
Parameter Expansion
︙
${!name[@]}
${!name[*]}List of array keys. If name is an array variable, expands to the list of array indices (keys) assigned in name. If name is not an array, expands to 0 if name is set and null otherwise. When
@is used and the expansion appears within double quotes, each key expands to a separate word.
