darcsPatchLevel :: ReleaseType -> C Int
darcsPatchLevel t =
           do patches' <- systemOut "darcs" ["changes","--from-tag",
                                             releaseRegexp t,"--count"]
              ((patches'',_):_) <- return $ reads patches'
              return $  max 0 (patches'' - 1)
darcsPatchLevel :: ReleaseType -> C Int
darcsPatchLevel t =
           do patches' <- systemOut "darcs" ["changes","--from-tag",
                                             releaseRegexp t,"--count"]
              ((patches'',_):_) <- return $ reads patches'
              return $  max 0 (patches'' - 1)
darcsPatchLevel t =
           do patches' <- systemOut "darcs" ["changes","--from-tag",
                                             releaseRegexp t,"--count"]
              ((patches'',_):_) <- return $ reads patches'
              return $  max 0 (patches'' - 1)