1 files changed, 5 insertions, 5 deletions

diff --git a/src/Network/BitTorrent/DHT/Routing.hs b/src/Network/BitTorrent/DHT/Routing.hs
index 8a6849a1..d64e415e 100644
--- a/src/Network/BitTorrent/DHT/Routing.hs
+++ b/src/Network/BitTorrent/DHT/Routing.hs
@@ -529,11 +529,11 @@ splitTip nid n i bucket
 -- k nodes in them.  Which subtrees I mean is illustrated in Fig 1. of Kademlia
 -- paper.  The rule requiring additional splits is in section 2.4.
 modifyBucket
-  :: forall f ip xs. (Alternative f, Eq ip) =>
-     NodeId -> (Bucket ip -> f (xs, Bucket ip)) -> Table ip -> f (xs,Table ip)
+  :: forall ip xs. (Eq ip) =>
+     NodeId -> (Bucket ip -> Maybe (xs, Bucket ip)) -> Table ip -> Maybe (xs,Table ip)
 modifyBucket nodeId f = go (0 :: BitIx)
   where
-    go :: BitIx -> Table ip -> f (xs, Table ip)
+    go :: BitIx -> Table ip -> Maybe (xs, Table ip)
     go i (Zero table  bucket)
       | testIdBit nodeId i  = second (Zero  table) <$> f bucket
       |     otherwise       = second (`Zero` bucket) <$> go (succ i) table
@@ -562,8 +562,8 @@ data CheckPing ip = CheckPing [NodeInfo ip]
 
 
 -- | Atomic 'Table' update
-insert :: (Alternative m, Eq ip) => Timestamp -> Event ip -> Table ip -> m ([CheckPing ip], Table ip)
-insert tm event = modifyBucket (eventId event) (insertBucket tm event)
+insert :: (Eq ip, Applicative m) => Timestamp -> Event ip -> Table ip -> m ([CheckPing ip], Table ip)
+insert tm event tbl = pure $ fromMaybe ([],tbl) $ modifyBucket (eventId event) (insertBucket tm event) tbl
 
 
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