Associative arrays: transitioning to Bash 4.0 and maintaining compatibility with older shells
Goal Create a single Bash script that leverages associative arrays for efficient key‑value lookups while remaining functional on systems that only provide Bash 3.x or earlier, where the -A option to declare is unavailable. The constraint is that attempting to declare an associative array on Bash 3.x produces a parsing error, preventing the script from starti