Get unique elements in Bash

uniqueElements.sh

function uniqueElements {
  local input_array=( "$@" )
  local IFS=$'\n'
  local RESULT=( $(printf '%s\n' ${input_array[@]} | awk '!seen[$0]++') )
  
  # Uncomment if you want the result to come back in a format that can easily be passed to `declare -a`
  #echo $(declare -p RESULT | sed "s/^[^(]*// ; s/'$//")
  
  echo "${RESULT[@]}"
}

# Run if not sourced
if [[ "$0" == "${BASH_SOURCE[0]}" ]]; then
    uniqueElements "$@"
fi