How to check if a array is empty in Bash

In this tutorial, we are going to learn about how to check if a array is empty or not in Bash.

Checking array is empty

To check if a array is empty or not, we can use the arithmetic expansion syntax (( )) in Bash.

Here is an example:

arr=()

if ((${#arr[@]})); then
  echo "array is not empty"
else
  echo  "array is empty"
fi

Output:

"array is empty"

or we can also check it like this:

arr=()

if [ ${#arr[@]} -gt 0 ]; then
  echo "array is not empty"
else
  echo  "array is empty"
fi

In the example above, this syntax ${#arr[@]} returns the total number of elements in an array.