cd.sh

  cd() {
    if [ $# -gt 1 ]; then
      echo "cd: too many arguments" >&2
      return 1
    fi

    if [ -d "$1" ]; then
      pushd "$1"
    elif [ "$1" == "-" ]; then
      popd
    elif [ "$1" == "--" ]; then
      pushd
    elif [ "$1" == "---" ]; then
      while popd -n &>/dev/null; do :; done
      dirs
    elif [ $# -eq 0 ]; then
      dirs
    else
      echo "cd: $1: No such file or directory" >&2
    fi
  }