345   $ hg cat b --rev .^

   345   $ hg cat b --rev .^

   346   b

   346   b

   347   $ hg cat b --rev 0

   347   $ hg cat b --rev 0

   348   b: no such file in rev 07f494440405

   348   b: no such file in rev 07f494440405

   349   [1]

   349   [1]

   350   $ hg uncommit --rev 0 b

   353   $ hg uncommit --rev 0 b

   351   $ hg cat b --rev .

   354   $ hg cat b --rev .

   352   b: no such file in rev 5b27f6b17da2

   355   b: no such file in rev 5b27f6b17da2

   353   [1]

   356   [1]

   354 

   357