add-path() {
  local path paths path_list=( )
  declare -A uniq_paths
  IFS=: read -ra paths <<< "$PATH"

  for path in "$@" "${paths[@]}"; do
    if [[ ! -v uniq_paths[$path] ]]; then
      uniq_paths[$path]=42
      path_list+=("$path")
    fi
  done

  printf -v path %s: "${path_list[@]}"
  export PATH=${path%:}
}