extends "cd" to accept (multiple) "dots" as indicator to traverse the directory tree up

cd

#
#  Copyright (C) 2015 Stefan Morgenthaler
#
#  This program is free software: you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation, either version 3 of the License, or
#  (at your option) any later version.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with this program. If not, see <http://www.gnu.org/licenses/>.
#

#
#  extends "cd" to accept (multiple) "dots" as indicator to traverse
#  the directory tree up.
#
#  usage/example:
#
#    $ pwd               # => /f/o/0/b/a/r/
#
#    $ cd ..    && pwd   # => /f/o/0/b/a/
#    $ cd ...   && pwd   # => /f/o/0/b/
#    $ cd ....  && pwd   # => /f/o/0/
#    $ cd ..... && pwd   # => /f/o/
#
#    $ cd ............ && pwd    # => /
#
#  howto use:
#
#    source <path_to_this_script>
#

function cd () {
  local  cdargs="${cdargs:=${@:1:$(($#-1))}}"; # $1 .. (n-1)
  local  cdpath="${@:$#}"; # n-th element (last)
  local cdnpath="";

  while [ "${cdpath:0:2}" == ".." ]; do
    cdpath=${cdpath/\.}; cdnpath+="../";
  done && cdnpath=${cdnpath}${cdpath/\.\/}

  builtin cd ${cdargs} ${cdnpath:-${cdpath}}
}

# vim: set ts=2 sw=2 tw=80 ft=sh et :