#!/bin/bash

set -euo pipefail

load_example usevars

# Arrays.

RED=(A B C)

usevars 'RED[1]=X'
usevars 'RED[2]' 'RED[3]'
declare -p RED

# Associative arrays.

usevars 'GREEN[abc]=X'

usevars GREEN 'GREEN[abc]' 'GREEN[def]'
declare -p GREEN
unset GREEN

declare -A GREEN
GREEN[B]=Y
usevars 'GREEN[Xyz]=AAA'
echo "${GREEN[B]} ${GREEN[Xyz]}"

# Unset.

usevars RED= YELLOW=
echo "${RED:-EMPTY}"
echo "${GREEN:-EMPTY}"