Oh dear :-)

On the same repository as issue1996 (waiting for permission to
distribute)

$ darcs get ~/PROJECTS/acl-11 --to-match 'touch METEO-PJE'
Unapplicable patch:
Thu Jan 14 16:43:00 GMT 2010  Eric Kow <E.Y.Kow@brighton.ac.uk>
  * Omit GREC-NEG ToDo from repo (can be regenerated).
darcs: ./GREC-NEG-RSE/ToDo: removeDirectory: unsatisified constraints (Directory not empty)

I bet we should be able to boil this one down later.

-- 
Eric Kow <http://www.nltg.brighton.ac.uk/home/Eric.Kow>
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Note also this variant

$ darcs unpull -p 'GREC'
Wed Feb  3 19:47:22 GMT 2010  Eric Kow <E.Y.Kow@brighton.ac.uk>
  * GREC-NEG-RSE: forgotten bits from the setup.
Shall I unpull this patch? (1/36)  [ynW...], or ? for more options: a
Really unpull all undecided patches? yes
WARNING: Doing a one-time conversion of pristine format.
This may take a while. The new format is backwards-compatible.
Pristine conversion done...                    

darcs failed:  No such file AnchoredPath [Name "GREC-NEG-RSE",Name 
"ToDo",Name "ls0_9"]