unify exception handling into Utility.Exception

Removed old extensible-exceptions, only needed for very old ghc.

Made webdav use Utility.Exception, to work after some changes in DAV's
exception handling.

Removed Annex.Exception. Mostly this was trivial, but note that
tryAnnex is replaced with tryNonAsync and catchAnnex replaced with
catchNonAsync. In theory that could be a behavior change, since the former
caught all exceptions, and the latter don't catch async exceptions.

However, in practice, nothing in the Annex monad uses async exceptions.
Grepping for throwTo and killThread only find stuff in the assistant,
which does not seem related.

Command.Add.undo is changed to accept a SomeException, and things
that use it for rollback now catch non-async exceptions, rather than
only IOExceptions.

1 files changed, 4 insertions, 4 deletions

diff --git a/Limit.hs b/Limit.hs
index 9ac849bce..89dd9d33e 100644
--- a/Limit.hs
+++ b/Limit.hs
@@ -152,8 +152,8 @@ limitCopies want = case split ":" want of
 	go num good = case readish num of
 		Nothing -> Left "bad number for copies"
 		Just n -> Right $ \notpresent -> checkKey $
-			handle n good notpresent
-	handle n good notpresent key = do
+			go' n good notpresent
+	go' n good notpresent key = do
 		us <- filter (`S.notMember` notpresent)
 			<$> (filterM good =<< Remote.keyLocations key)
 		return $ length us >= n
@@ -170,10 +170,10 @@ addLackingCopies approx = addLimit . limitLackingCopies approx
 limitLackingCopies :: Bool -> MkLimit Annex
 limitLackingCopies approx want = case readish want of
 	Just needed -> Right $ \notpresent mi -> flip checkKey mi $
-		handle mi needed notpresent
+		go mi needed notpresent
 	Nothing -> Left "bad value for number of lacking copies"
   where
-	handle mi needed notpresent key = do
+	go mi needed notpresent key = do
 		NumCopies numcopies <- if approx
 			then approxNumCopies
 			else case mi of