$ commit()

  > {

  >     msg=$1

  >     p1=$2

  >     p2=$3

  > 

  >     if [ "$p1" ]; then

  >         hg up -qC $p1

  >     fi

  > 

  >     if [ "$p2" ]; then

  >         HGMERGE=true hg merge -q $p2

  >     fi

  > 

  >     echo >> foo

  > 

  >     hg commit -qAm "$msg"

  > }

  $ hg init repo

  $ cd repo

  $ echo '[extensions]' > .hg/hgrc

  $ echo 'parentrevspec =' >> .hg/hgrc

  $ commit '0: add foo'

  $ commit '1: change foo 1'

  $ commit '2: change foo 2a'

  $ commit '3: change foo 3a'

  $ commit '4: change foo 2b' 1

  $ commit '5: merge' 3 4

  $ commit '6: change foo again'

  $ hg log --template '{rev}:{node|short} {parents}\n'

  6:755d1e0d79e9 

  5:9ce2ce29723a 3:a3e00c7dbf11 4:bb4475edb621 

  4:bb4475edb621 1:5d953a1917d1 

  3:a3e00c7dbf11 

  2:befc7d89d081 

  1:5d953a1917d1 

  0:837088b6e1d9 

  $ echo

  $ lookup()

  > {

  >     for rev in "$@"; do

  >         printf "$rev: "

  >         hg id -nr $rev

  >     done

  >     true

  > }

  $ tipnode=`hg id -ir tip`

should work with tag/branch/node/rev

  $ for r in tip default $tipnode 6; do

  >     lookup "$r^"

  > done

  tip^: 5

  default^: 5

  755d1e0d79e9^: 5

  6^: 5

  $ echo

some random lookups

  $ lookup "6^^" "6^^^" "6^^^^" "6^^^^^" "6^^^^^^" "6^1" "6^2" "6^^2" "6^1^2" "6^^3"

  6^^: 3

  6^^^: 2

  6^^^^: 1

  6^^^^^: 0

  6^^^^^^: -1

  6^1: 5

  6^2: hg: parse error at 1: syntax error

  6^^2: 4

  6^1^2: 4

  6^^3: hg: parse error at 1: syntax error

  $ lookup "6~" "6~1" "6~2" "6~3" "6~4" "6~5" "6~42" "6~1^2" "6~1^2~2"

  6~: hg: parse error at 1: syntax error

  6~1: 5

  6~2: 3

  6~3: 2

  6~4: 1

  6~5: 0

  6~42: -1

  6~1^2: 4

  6~1^2~2: 0

  $ echo

with a tag "6^" pointing to rev 1

  $ hg tag -l -r 1 "6^"

  $ lookup "6^" "6^1" "6~1" "6^^"

  6^: 1

  6^1: 5

  6~1: 5

  6^^: 3

  $ echo

with a tag "foo^bar" pointing to rev 2

  $ hg tag -l -r 2 "foo^bar"

  $ lookup "foo^bar" "foo^bar^"

  foo^bar: 2

  foo^bar^: hg: parse error at 3: syntax error