Bash - variable variables
In bash, you can use ${!variable}
to use variable variables.
foo="something"
bar="foo"
echo "${!bar}"
# something
The accepted answer is great. However, @Edison asked how to do the same for arrays. The trick is that you want your variable holding the "[@]", so that the array is expanded with the "!". Check out this function to dump variables:
$ function dump_variables() {
for var in "$@"; do
echo "$var=${!var}"
done
}
$ STRING="Hello World"
$ ARRAY=("ab" "cd")
$ dump_variables STRING ARRAY ARRAY[@]
This outputs:
STRING=Hello World
ARRAY=ab
ARRAY[@]=ab cd
When given as just ARRAY
, the first element is shown as that's what's expanded by the !
. By giving the ARRAY[@]
format, you get the array and all its values expanded.
eval echo \"\$$bar\"
would do it.