bd () {
  (($#<1)) && {
    print -- "usage: $0 <name-of-any-parent-directory>"
    return 1
  } >&2
  # Get parents (in reverse order)
  local parents
  local num=${#${(ps:/:)${PWD}}}
  local i
  for i in {$((num+1))..2}
  do
    parents=($parents "`echo $PWD | cut -d'/' -f$i`")
  done
  parents=($parents "/")
  # Build dest and 'cd' to it
  local dest="./"
  local parent
  foreach parent (${parents})
  do
    if [[ $1 == $parent ]]
    then
      cd $dest
      return 0
    fi
    dest+="../"
  done
  print -- "bd: Error: No parent directory named '$1'"
  return 1
}
_bd () {
  # Get parents (in reverse order)
  local num=${#${(ps:/:)${PWD}}}
  local i
  for i in {$((num+1))..2}
  do
    reply=($reply "`echo $PWD | cut -d'/' -f$i`")
  done
  reply=($reply "/")
}
compctl -V directories -K _bd bd