finished hlint pass

29 files changed, 114 insertions, 115 deletions

diff --git a/Command/Add.hs b/Command/Add.hs
index 51b95b9b5..58c0143dd 100644
--- a/Command/Add.hs
+++ b/Command/Add.hs
@@ -39,7 +39,7 @@ seek = [withFilesNotInGit start, withFilesUnlocked start]
 start :: CommandStartBackendFile
 start pair@(file, _) = notAnnexed file $ do
 	s <- liftIO $ getSymbolicLinkStatus file
-	if (isSymbolicLink s) || (not $ isRegularFile s)
+	if isSymbolicLink s || not (isRegularFile s)
 		then stop
 		else do
 			showStart "add" file
@@ -58,8 +58,8 @@ perform (file, backend) = do
  - This can be called before or after the symlink is in place. -}
 undo :: FilePath -> Key -> IOException -> Annex a
 undo file key e = do
-	unlessM (inAnnex key) $ rethrow -- no cleanup to do
-	liftIO $ whenM (doesFileExist file) $ do removeFile file
+	unlessM (inAnnex key) rethrow -- no cleanup to do
+	liftIO $ whenM (doesFileExist file) $ removeFile file
 	handle tryharder $ fromAnnex key file
 	logStatus key InfoMissing
 	rethrow
diff --git a/Command/DropUnused.hs b/Command/DropUnused.hs
index 55007c1f7..a01e08ab5 100644
--- a/Command/DropUnused.hs
+++ b/Command/DropUnused.hs
@@ -49,7 +49,7 @@ start (unused, unusedbad, unusedtmp) s = notBareRepo $ search
 	]
 	where
 		search [] = stop
-		search ((m, a):rest) = do
+		search ((m, a):rest) =
 			case M.lookup s m of
 				Nothing -> search rest
 				Just key -> do
@@ -78,10 +78,9 @@ readUnusedLog prefix = do
 	let f = gitAnnexUnusedLog prefix g
 	e <- liftIO $ doesFileExist f
 	if e
-		then do
-			l <- liftIO $ readFile f
-			return $ M.fromList $ map parse $ lines l
-		else return $ M.empty
+		then return . M.fromList . map parse . lines
+			=<< liftIO (readFile f)
+		else return M.empty
 	where
 		parse line = (head ws, fromJust $ readKey $ unwords $ tail ws)
 			where
diff --git a/Command/Fsck.hs b/Command/Fsck.hs
index ec3f1d8e7..0d3ecb58f 100644
--- a/Command/Fsck.hs
+++ b/Command/Fsck.hs
@@ -94,7 +94,7 @@ fsckKey :: Backend Annex -> Key -> Maybe FilePath -> Maybe Int -> Annex Bool
 fsckKey backend key file numcopies = do
 	size_ok <- checkKeySize key
 	copies_ok <- checkKeyNumCopies key file numcopies
-	backend_ok <-(Types.Backend.fsckKey backend) key
+	backend_ok <- (Types.Backend.fsckKey backend) key
 	return $ size_ok && copies_ok && backend_ok
 
 {- The size of the data for a key is checked against the size encoded in
diff --git a/Command/InAnnex.hs b/Command/InAnnex.hs
index b5b59ccf7..24f7162ac 100644
--- a/Command/InAnnex.hs
+++ b/Command/InAnnex.hs
@@ -25,4 +25,4 @@ start key = do
 	present <- inAnnex key
 	if present
 		then stop
-		else liftIO $ exitFailure
+		else liftIO exitFailure
diff --git a/Command/InitRemote.hs b/Command/InitRemote.hs
index 15962ad99..9859308e5 100644
--- a/Command/InitRemote.hs
+++ b/Command/InitRemote.hs
@@ -24,7 +24,7 @@ import Messages
 command :: [Command]
 command = [repoCommand "initremote"
 	(paramPair paramName $
-		paramOptional $ paramRepeating $ paramKeyValue) seek
+		paramOptional $ paramRepeating paramKeyValue) seek
 	"sets up a special (non-git) remote"]
 
 seek :: [CommandSeek]
@@ -32,7 +32,7 @@ seek = [withWords start]
 
 start :: CommandStartWords
 start ws = do
-	when (null ws) $ needname
+	when (null ws) needname
 
 	(u, c) <- findByName name
 	let fullconfig = M.union config c	
@@ -69,7 +69,7 @@ findByName name = do
 	maybe generate return $ findByName' name m
 	where
 		generate = do
-			uuid <- liftIO $ genUUID
+			uuid <- liftIO genUUID
 			return (uuid, M.insert nameKey name M.empty)
 
 findByName' :: String ->  M.Map UUID R.RemoteConfig -> Maybe (UUID, R.RemoteConfig)
@@ -85,7 +85,7 @@ findByName' n m = if null matches then Nothing else Just $ head matches
 remoteNames :: Annex [String]
 remoteNames = do
 	m <- RemoteLog.readRemoteLog
-	return $ catMaybes $ map ((M.lookup nameKey) . snd) $ M.toList m
+	return $ mapMaybe (M.lookup nameKey . snd) $ M.toList m
 
 {- find the specified remote type -}
 findType :: R.RemoteConfig -> Annex (R.RemoteType Annex)
diff --git a/Command/Map.hs b/Command/Map.hs
index 0391ab8e8..557ae2787 100644
--- a/Command/Map.hs
+++ b/Command/Map.hs
@@ -12,6 +12,7 @@ import Control.Exception.Extensible
 import System.Cmd.Utils
 import qualified Data.Map as M
 import Data.List.Utils
+import Data.Maybe
 
 import Command
 import qualified Annex
@@ -58,7 +59,7 @@ start = do
  - the repositories first, followed by uuids that were not matched
  - to a repository.
  -}
-drawMap :: [Git.Repo] -> (M.Map UUID String) -> [UUID] -> String
+drawMap :: [Git.Repo] -> M.Map UUID String -> [UUID] -> String
 drawMap rs umap ts = Dot.graph $ repos ++ trusted ++ others
 	where
 		repos = map (node umap rs) rs
@@ -78,23 +79,23 @@ basehostname r = head $ split "." $ hostname r
 
 {- A name to display for a repo. Uses the name from uuid.log if available,
  - or the remote name if not. -}
-repoName :: (M.Map UUID String) -> Git.Repo -> String
+repoName :: M.Map UUID String -> Git.Repo -> String
 repoName umap r
 	| null repouuid = fallback
 	| otherwise = M.findWithDefault fallback repouuid umap
 	where
 		repouuid = getUncachedUUID r
-		fallback = maybe "unknown" id $ Git.repoRemoteName r
+		fallback = fromMaybe "unknown" $ Git.repoRemoteName r
 
 {- A unique id for the node for a repo. Uses the annex.uuid if available. -}
 nodeId :: Git.Repo -> String
 nodeId r =
-	case (getUncachedUUID r) of
+	case getUncachedUUID r of
 		"" -> Git.repoLocation r
 		u -> u
 
 {- A node representing a repo. -}
-node :: (M.Map UUID String) -> [Git.Repo] -> Git.Repo -> String
+node :: M.Map UUID String -> [Git.Repo] -> Git.Repo -> String
 node umap fullinfo r = unlines $ n:edges
 	where
 		n = Dot.subGraph (hostname r) (basehostname r) "lightblue" $
@@ -105,14 +106,14 @@ node umap fullinfo r = unlines $ n:edges
 			| otherwise = reachable
 
 {- An edge between two repos. The second repo is a remote of the first. -}
-edge :: (M.Map UUID String) -> [Git.Repo] -> Git.Repo -> Git.Repo -> String	
+edge :: M.Map UUID String -> [Git.Repo] -> Git.Repo -> Git.Repo -> String	
 edge umap fullinfo from to =
 	Dot.graphEdge (nodeId from) (nodeId fullto) edgename
 	where
 		-- get the full info for the remote, to get its UUID
 		fullto = findfullinfo to
 		findfullinfo n =
-			case (filter (same n) fullinfo) of
+			case filter (same n) fullinfo of
 				[] -> n
 				(n':_) -> n'
 		{- Only name an edge if the name is different than the name
@@ -120,7 +121,7 @@ edge umap fullinfo from to =
 		 - different from its hostname. (This reduces visual clutter.) -}
 		edgename = maybe Nothing calcname $ Git.repoRemoteName to
 		calcname n
-			| n == repoName umap fullto || n == hostname fullto = Nothing
+			| n `elem` [repoName umap fullto, hostname fullto] = Nothing
 			| otherwise = Just n
 
 unreachable :: String -> String
@@ -188,7 +189,7 @@ tryScan r
 	| otherwise = safely $ Git.configRead r
 	where
 		safely a = do
-			result <- liftIO (try (a)::IO (Either SomeException Git.Repo))
+			result <- liftIO (try a :: IO (Either SomeException Git.Repo))
 			case result of
 				Left _ -> return Nothing
 				Right r' -> return $ Just r'
diff --git a/Command/Move.hs b/Command/Move.hs
index 6bf6e0582..a98276e7e 100644
--- a/Command/Move.hs
+++ b/Command/Move.hs
@@ -124,7 +124,7 @@ fromStart src move file = isAnnexed file $ \(key, _) -> do
 	g <- Annex.gitRepo
 	u <- getUUID g
 	remotes <- Remote.keyPossibilities key
-	if (u == Remote.uuid src) || (null $ filter (== src) remotes)
+	if u == Remote.uuid src || not (any (== src) remotes)
 		then stop
 		else do
 			showAction move file
diff --git a/Command/SetKey.hs b/Command/SetKey.hs
index b000a4e8b..f2a5259ba 100644
--- a/Command/SetKey.hs
+++ b/Command/SetKey.hs
@@ -16,7 +16,7 @@ import Content
 import Messages
 
 command :: [Command]
-command = [repoCommand "setkey" (paramPath) seek
+command = [repoCommand "setkey" paramPath seek
 	"sets annexed content for a key using a temp file"]
 
 seek :: [CommandSeek]
@@ -34,7 +34,7 @@ perform file = do
 	-- the file might be on a different filesystem, so mv is used
 	-- rather than simply calling moveToObjectDir; disk space is also
 	-- checked this way.
-	ok <- getViaTmp key $ \dest -> do
+	ok <- getViaTmp key $ \dest ->
 		if dest /= file
 			then liftIO $
 				boolSystem "mv" [File file, File dest]
diff --git a/Command/Status.hs b/Command/Status.hs
index 1ec478236..aef4df232 100644
--- a/Command/Status.hs
+++ b/Command/Status.hs
@@ -32,8 +32,8 @@ type Stat = StatState (Maybe (String, StatState String))
 
 -- cached info that multiple Stats may need
 data StatInfo = StatInfo
-	{ keysPresentCache :: (Maybe (SizeList Key))
-	, keysReferencedCache :: (Maybe (SizeList Key))
+	{ keysPresentCache :: Maybe (SizeList Key)
+	, keysReferencedCache :: Maybe (SizeList Key)
 	}
 
 -- a state monad for running Stats in
@@ -84,7 +84,7 @@ stat :: String -> StatState String -> Stat
 stat desc a = return $ Just (desc, a)
 
 nostat :: Stat
-nostat = return $ Nothing
+nostat = return Nothing
 
 showStat :: Stat -> StatState ()
 showStat s = calc =<< s
@@ -144,7 +144,7 @@ cachedKeysPresent = do
 	case keysPresentCache s of
 		Just v -> return v
 		Nothing -> do
-			keys <- lift $ getKeysPresent
+			keys <- lift getKeysPresent
 			let v = sizeList keys
 			put s { keysPresentCache = Just v }
 			return v
@@ -155,7 +155,7 @@ cachedKeysReferenced = do
 	case keysReferencedCache s of
 		Just v -> return v
 		Nothing -> do
-			keys <- lift $ Command.Unused.getKeysReferenced
+			keys <- lift Command.Unused.getKeysReferenced
 			-- A given key may be referenced repeatedly.
 			-- nub does not seem too slow (yet)..
 			let v = sizeList $ nub keys
@@ -164,9 +164,9 @@ cachedKeysReferenced = do
 
 keySizeSum :: SizeList Key -> StatState String
 keySizeSum (keys, len) = do
-	let knownsize = catMaybes $ map keySize keys
-	let total = roughSize storageUnits False $ foldl (+) 0 knownsize
-	let missing = len - genericLength knownsize
+	let knownsizes = mapMaybe keySize keys
+	let total = roughSize storageUnits False $ sum knownsizes
+	let missing = len - genericLength knownsizes
 	return $ total ++
 		if missing > 0
 			then aside $ "but " ++ show missing ++ " keys have unknown size"
diff --git a/Command/Uninit.hs b/Command/Uninit.hs
index 1497bbfd1..8b8d7e364 100644
--- a/Command/Uninit.hs
+++ b/Command/Uninit.hs
@@ -52,8 +52,9 @@ cleanup = do
 	liftIO $ removeDirectoryRecursive (gitAnnexDir g)
 	-- avoid normal shutdown
 	saveState
-	liftIO $ Git.run g "branch" [Param "-D", Param Branch.name]
-	liftIO $ exitSuccess
+	liftIO $ do
+		Git.run g "branch" [Param "-D", Param Branch.name]
+		exitSuccess
 
 gitPreCommitHookUnWrite :: Git.Repo -> Annex ()
 gitPreCommitHookUnWrite repo = do
diff --git a/Command/Unused.hs b/Command/Unused.hs
index 3f51e2c2c..870c993f1 100644
--- a/Command/Unused.hs
+++ b/Command/Unused.hs
@@ -7,7 +7,7 @@
 
 module Command.Unused where
 
-import Control.Monad (filterM, unless, forM_, when)
+import Control.Monad (filterM, unless, forM_)
 import Control.Monad.State (liftIO)
 import qualified Data.Set as S
 import Data.Maybe
@@ -55,9 +55,9 @@ checkUnused = do
 	where
 		list file msg l c = do
 			let unusedlist = number c l
-			when (not $ null l) $ do
+			unless (null l) $ do
 				showLongNote $ msg unusedlist
-				showLongNote $ "\n"
+				showLongNote "\n"
 			writeUnusedFile file unusedlist
 			return $ c + length l
 
@@ -68,7 +68,7 @@ checkRemoteUnused name = do
 
 checkRemoteUnused' :: Remote.Remote Annex -> Annex ()
 checkRemoteUnused' r = do
-	showNote $ "checking for unused data..."
+	showNote "checking for unused data..."
 	referenced <- getKeysReferenced
 	remotehas <- filterM isthere =<< loggedKeys
 	let remoteunused = remotehas `exclude` referenced
@@ -76,7 +76,7 @@ checkRemoteUnused' r = do
 	writeUnusedFile "" list
 	unless (null remoteunused) $ do
 		showLongNote $ remoteUnusedMsg r list
-		showLongNote $ "\n"
+		showLongNote "\n"
 	where
 		isthere k = do
 			us <- keyLocations k
@@ -90,14 +90,14 @@ writeUnusedFile prefix l = do
 		unlines $ map (\(n, k) -> show n ++ " " ++ show k) l
 
 table :: [(Int, Key)] -> [String]
-table l = ["  NUMBER  KEY"] ++ map cols l
+table l = "  NUMBER  KEY" : map cols l
 	where
 		cols (n,k) = "  " ++ pad 6 (show n) ++ "  " ++ show k
 		pad n s = s ++ replicate (n - length s) ' '
 
 number :: Int -> [a] -> [(Int, a)]
 number _ [] = []
-number n (x:xs) = (n+1, x):(number (n+1) xs)
+number n (x:xs) = (n+1, x) : number (n+1) xs
 
 staleTmpMsg :: [(Int, Key)] -> String
 staleTmpMsg t = unlines $ 
@@ -210,4 +210,4 @@ staleKeys dirspec = do
 			contents <- liftIO $ getDirectoryContents dir
 			files <- liftIO $ filterM doesFileExist $
 				map (dir </>) contents
-			return $ catMaybes $ map (fileKey . takeFileName) files
+			return $ mapMaybe (fileKey . takeFileName) files
diff --git a/Command/Version.hs b/Command/Version.hs
index bb7acd12d..2392c9bf6 100644
--- a/Command/Version.hs
+++ b/Command/Version.hs
@@ -31,4 +31,4 @@ start = do
 	liftIO $ putStrLn $ "upgrade supported from repository versions: " ++ vs upgradableVersions
 	stop
 	where
-		vs l = join " " l
+		vs = join " "
diff --git a/Command/Whereis.hs b/Command/Whereis.hs
index 0e4858f8b..05748e8d6 100644
--- a/Command/Whereis.hs
+++ b/Command/Whereis.hs
@@ -30,11 +30,11 @@ perform key = do
 	uuids <- keyLocations key
 	let num = length uuids
 	showNote $ show num ++ " " ++ copiesplural num
-	if null $ uuids
+	if null uuids
 		then stop
 		else do
 			pp <- prettyPrintUUIDs uuids
-			showLongNote $ pp
+			showLongNote pp
 			showProgress	
 			next $ return True
 	where
diff --git a/Locations.hs b/Locations.hs
index 2dbf2f55e..942b687bb 100644
--- a/Locations.hs
+++ b/Locations.hs
@@ -167,8 +167,8 @@ display_32bits_as_dir w = trim $ swap_pairs cs
 		-- a real word, use letters that appear less frequently.
 		chars = ['0'..'9'] ++ "zqjxkmvwgpfZQJXKMVWGPF"
 		cs = map (\x -> getc $ (shiftR w (6*x)) .&. 31) [0..7]
-		getc n = chars !! (fromIntegral n)
+		getc n = chars !! fromIntegral n
 		swap_pairs (x1:x2:xs) = x2:x1:swap_pairs xs
 		swap_pairs _ = []
 		-- Last 2 will always be 00, so omit.
-		trim s = take 6 s
+		trim = take 6
diff --git a/Remote/Bup.hs b/Remote/Bup.hs
index 5a44397f0..4ea455226 100644
--- a/Remote/Bup.hs
+++ b/Remote/Bup.hs
@@ -8,7 +8,8 @@
 module Remote.Bup (remote) where
 
 import qualified Data.ByteString.Lazy.Char8 as L
-import IO
+import System.IO
+import System.IO.Error
 import Control.Exception.Extensible (IOException)
 import qualified Data.Map as M
 import Control.Monad (when)
@@ -16,6 +17,7 @@ import Control.Monad.State (liftIO)
 import System.Process
 import System.Exit
 import System.FilePath
+import Data.Maybe
 import Data.List.Utils
 import System.Cmd.Utils
 
@@ -68,7 +70,7 @@ gen r u c = do
 bupSetup :: UUID -> RemoteConfig -> Annex RemoteConfig
 bupSetup u c = do
 	-- verify configuration is sane
-	let buprepo = maybe (error "Specify buprepo=") id $
+	let buprepo = fromMaybe (error "Specify buprepo=") $
 		M.lookup "buprepo" c
 	c' <- encryptionSetup c
 
@@ -87,7 +89,7 @@ bupSetup u c = do
 
 bupParams :: String -> BupRepo -> [CommandParam] -> [CommandParam]
 bupParams command buprepo params = 
-	(Param command) : [Param "-r", Param buprepo] ++ params
+	Param command : [Param "-r", Param buprepo] ++ params
 
 bup :: String -> BupRepo -> [CommandParam] -> Annex Bool
 bup command buprepo params = do
@@ -123,8 +125,8 @@ storeEncrypted r buprepo (cipher, enck) k = do
 	g <- Annex.gitRepo
 	let src = gitAnnexLocation g k
 	params <- bupSplitParams r buprepo enck (Param "-")
-	liftIO $ catchBool $ do
-		withEncryptedHandle cipher (L.readFile src) $ \h -> do
+	liftIO $ catchBool $
+		withEncryptedHandle cipher (L.readFile src) $ \h ->
 			pipeBup params (Just h) Nothing
 
 retrieve :: BupRepo -> Key -> FilePath -> Annex Bool
@@ -184,7 +186,7 @@ onBupRemote :: Git.Repo -> (FilePath -> [CommandParam] -> IO a) -> FilePath -> [
 onBupRemote r a command params = do
 	let dir = shellEscape (Git.workTree r)
 	sshparams <- sshToRepo r [Param $
-			"cd " ++ dir ++ " && " ++ (unwords $ command : toCommand params)]
+			"cd " ++ dir ++ " && " ++ unwords (command : toCommand params)]
 	liftIO $ a "ssh" sshparams
 
 {- Allow for bup repositories on removable media by checking
@@ -215,20 +217,20 @@ bup2GitRemote "" = do
 	Git.repoFromAbsPath $ h </> ".bup"
 bup2GitRemote r
 	| bupLocal r = 
-		if r !! 0 == '/'
+		if head r == '/'
 			then Git.repoFromAbsPath r
 			else error "please specify an absolute path"
 	| otherwise = Git.repoFromUrl $ "ssh://" ++ host ++ slash dir
 		where
 			bits = split ":" r
-			host = bits !! 0
+			host = head bits
 			dir = join ":" $ drop 1 bits
 			-- "host:~user/dir" is not supported specially by bup;
 			-- "host:dir" is relative to the home directory;
 			-- "host:" goes in ~/.bup
 			slash d
 				| d == "" = "/~/.bup"
-				| d !! 0 == '/' = d
+				| head d == '/' = d
 				| otherwise = "/~/" ++ d
 
 bupLocal :: BupRepo -> Bool
diff --git a/Remote/Directory.hs b/Remote/Directory.hs
index 05d42136f..235f61300 100644
--- a/Remote/Directory.hs
+++ b/Remote/Directory.hs
@@ -8,13 +8,14 @@
 module Remote.Directory (remote) where
 
 import qualified Data.ByteString.Lazy.Char8 as L
-import IO
+import System.IO.Error
 import Control.Exception.Extensible (IOException)
 import qualified Data.Map as M
 import Control.Monad (when)
 import Control.Monad.State (liftIO)
 import System.Directory hiding (copyFile)
 import System.FilePath
+import Data.Maybe
 
 import Types
 import Types.Remote
@@ -60,7 +61,7 @@ gen r u c = do
 directorySetup :: UUID -> RemoteConfig -> Annex RemoteConfig
 directorySetup u c = do
 	-- verify configuration is sane
-	let dir = maybe (error "Specify directory=") id $
+	let dir = fromMaybe (error "Specify directory=") $
 		M.lookup "directory" c
 	liftIO $ doesDirectoryExist dir
 		>>! error $ "Directory does not exist: " ++ dir
diff --git a/Remote/Encryptable.hs b/Remote/Encryptable.hs
index 443f5cf83..66e1738ac 100644
--- a/Remote/Encryptable.hs
+++ b/Remote/Encryptable.hs
@@ -56,10 +56,10 @@ encryptableRemote c storeKeyEncrypted retrieveKeyFileEncrypted r =
 	where
 		store k = cip k >>= maybe
 			(storeKey r k)
-			(\x -> storeKeyEncrypted x k)
+			(`storeKeyEncrypted` k)
 		retrieve k f = cip k >>= maybe
 			(retrieveKeyFile r k f)
-			(\x -> retrieveKeyFileEncrypted x f)
+			(`retrieveKeyFileEncrypted` f)
 		withkey a k = cip k >>= maybe (a k) (a . snd)
 		cip = cipherKey c
 
diff --git a/Remote/Git.hs b/Remote/Git.hs
index fb8512382..1f22ad11c 100644
--- a/Remote/Git.hs
+++ b/Remote/Git.hs
@@ -57,7 +57,7 @@ gen r u _ = do
 	let defcst = if cheap then cheapRemoteCost else expensiveRemoteCost
 	cst <- remoteCost r' defcst
 
-	return $ Remote {
+	return Remote {
 		uuid = u',
 		cost = cst,
 		name = Git.repoDescribe r',
@@ -81,7 +81,7 @@ tryGitConfigRead r
 		-- Reading config can fail due to IO error or
 		-- for other reasons; catch all possible exceptions.
 		safely a = do
-			result <- liftIO (try (a)::IO (Either SomeException Git.Repo))
+			result <- liftIO (try a :: IO (Either SomeException Git.Repo))
 			case result of
 				Left _ -> return r
 				Right r' -> return r'
@@ -154,7 +154,7 @@ copyToRemote r key
 		rsyncHelper =<< rsyncParamsRemote r False key keysrc
 	| otherwise = error "copying to non-ssh repo not supported"
 
-rsyncHelper :: [CommandParam] -> Annex (Bool)
+rsyncHelper :: [CommandParam] -> Annex Bool
 rsyncHelper p = do
 	showProgress -- make way for progress bar
 	res <- liftIO $ rsync p
diff --git a/Remote/Hook.hs b/Remote/Hook.hs
index 86a7bca56..f0e4d5bfb 100644
--- a/Remote/Hook.hs
+++ b/Remote/Hook.hs
@@ -17,6 +17,7 @@ import System.Posix.IO
 import System.IO
 import System.IO.Error (try)
 import System.Exit
+import Data.Maybe
 
 import Types
 import Types.Remote
@@ -61,7 +62,7 @@ gen r u c = do
 
 hookSetup :: UUID -> RemoteConfig -> Annex RemoteConfig
 hookSetup u c = do
-	let hooktype = maybe (error "Specify hooktype=") id $
+	let hooktype = fromMaybe (error "Specify hooktype=") $
 		M.lookup "hooktype" c
 	c' <- encryptionSetup c
 	gitConfigSpecialRemote u c' "hooktype" hooktype
@@ -73,12 +74,13 @@ hookEnv k f = Just $ fileenv f ++ keyenv
 		env s v = ("ANNEX_" ++ s, v)
 		keyenv =
 			[ env "KEY" (show k)
-			, env "HASH_1" (hashbits !! 0)
-			, env "HASH_2" (hashbits !! 1)
+			, env "HASH_1" hash_1
+			, env "HASH_2" hash_2
 			]
 		fileenv Nothing = []
 		fileenv (Just file) =  [env "FILE" file]
-		hashbits = map takeDirectory $ splitPath $ hashDirMixed k
+		[hash_1, hash_2, _rest] =
+			map takeDirectory $ splitPath $ hashDirMixed k
 
 lookupHook :: String -> String -> Annex (Maybe String)
 lookupHook hooktype hook =do
@@ -127,7 +129,7 @@ retrieveEncrypted h (cipher, enck) f = withTmp enck $ \tmp ->
 		return True
 
 remove :: String -> Key -> Annex Bool
-remove h k = runHook h "remove" k Nothing $ do return True
+remove h k = runHook h "remove" k Nothing $ return True
 
 checkPresent :: Git.Repo -> String -> Key -> Annex (Either IOException Bool)
 checkPresent r h k = do
@@ -135,7 +137,7 @@ checkPresent r h k = do
 	v <- lookupHook h "checkpresent"
 	liftIO (try (check v) ::IO (Either IOException Bool))
 	where
-		findkey s = (show k) `elem` (lines s)
+		findkey s = show k `elem` lines s
 		env = hookEnv k Nothing
 		check Nothing = error "checkpresent hook misconfigured"
 		check (Just hook) = do
@@ -150,5 +152,5 @@ checkPresent r h k = do
 			hClose fromh
 			s <- getProcessStatus True False pid
 			case s of
-				Just (Exited (ExitSuccess)) -> return $ findkey reply
+				Just (Exited ExitSuccess) -> return $ findkey reply
 				_ -> error "checkpresent hook failed"
diff --git a/Remote/Rsync.hs b/Remote/Rsync.hs
index 80e194fed..ca4236276 100644
--- a/Remote/Rsync.hs
+++ b/Remote/Rsync.hs
@@ -15,6 +15,7 @@ import System.FilePath
 import System.Directory
 import System.Posix.Files
 import System.Posix.Process
+import Data.Maybe
 
 import Types
 import Types.Remote
@@ -82,7 +83,7 @@ genRsyncOpts r = do
 rsyncSetup :: UUID -> RemoteConfig -> Annex RemoteConfig
 rsyncSetup u c = do
 	-- verify configuration is sane
-	let url = maybe (error "Specify rsyncurl=") id $
+	let url = fromMaybe (error "Specify rsyncurl=") $
 		M.lookup "rsyncurl" c
 	c' <- encryptionSetup c
 
@@ -160,10 +161,10 @@ partialParams = Params "--no-inplace --partial --partial-dir=.rsync-partial"
 withRsyncScratchDir :: (FilePath -> Annex Bool) -> Annex Bool
 withRsyncScratchDir a = do
 	g <- Annex.gitRepo
-	pid <- liftIO $ getProcessID
+	pid <- liftIO getProcessID
 	let tmp = gitAnnexTmpDir g </> "rsynctmp" </> show pid
 	nuke tmp
-	liftIO $ createDirectoryIfMissing True $ tmp
+	liftIO $ createDirectoryIfMissing True tmp
 	res <- a tmp
 	nuke tmp
 	return res
@@ -189,15 +190,14 @@ rsyncRemote o params = do
 rsyncSend :: RsyncOpts -> Key -> FilePath -> Annex Bool
 rsyncSend o k src = withRsyncScratchDir $ \tmp -> do
 	let dest = tmp </> hashDirMixed k </> f </> f
-	liftIO $ createDirectoryIfMissing True $ parentDir $ dest
+	liftIO $ createDirectoryIfMissing True $ parentDir dest
 	liftIO $ createLink src dest
-	res <- rsyncRemote o
+	rsyncRemote o
 		[ Param "--recursive"
 		, partialParams
  		  -- tmp/ to send contents of tmp dir
 		, Param $ addTrailingPathSeparator tmp
 		, Param $ rsyncUrl o
 		]
-	return res
 	where
 		f = keyFile k
diff --git a/Remote/S3real.hs b/Remote/S3real.hs
index 52d1ed1be..cbd3ef622 100644
--- a/Remote/S3real.hs
+++ b/Remote/S3real.hs
@@ -52,7 +52,7 @@ gen r u c = do
 	cst <- remoteCost r expensiveRemoteCost
 	return $ gen' r u c cst
 gen' :: Git.Repo -> UUID -> Maybe RemoteConfig -> Int -> Remote Annex
-gen' r u c cst = do
+gen' r u c cst =
 	encryptableRemote c
 		(storeEncrypted this)
 		(retrieveEncrypted this)
@@ -85,7 +85,7 @@ s3Setup u c = handlehost $ M.lookup "host" c
 		
 		handlehost Nothing = defaulthost
 		handlehost (Just h)
-			| ".archive.org" `isSuffixOf` (map toLower h) = archiveorg
+			| ".archive.org" `isSuffixOf` map toLower h = archiveorg
 			| otherwise = defaulthost
 
 		use fullconfig = do
@@ -99,7 +99,7 @@ s3Setup u c = handlehost $ M.lookup "host" c
 			use fullconfig
 
 		archiveorg = do
-			showNote $ "Internet Archive mode"
+			showNote "Internet Archive mode"
 			maybe (error "specify bucket=") (const $ return ()) $
 				M.lookup "bucket" archiveconfig
 			use archiveconfig
@@ -203,10 +203,8 @@ s3Error :: ReqError -> a
 s3Error e = error $ prettyReqError e
 
 s3Bool :: AWSResult () -> Annex Bool
-s3Bool res = do
-	case res of
-		Right _ -> return True
-		Left e -> s3Warning e
+s3Bool (Right _) = return True
+s3Bool (Left e) = s3Warning e
 
 s3Action :: Remote Annex -> a -> ((AWSConnection, String) -> Annex a) -> Annex a
 s3Action r noconn action = do
@@ -219,7 +217,7 @@ s3Action r noconn action = do
 		_ -> return noconn
 
 bucketFile :: Remote Annex -> Key -> FilePath
-bucketFile r k = (munge $ show k)
+bucketFile r = munge . show
 	where
 		munge s = case M.lookup "mungekeys" $ fromJust $ config r of
 			Just "ia" -> iaMunge s
@@ -271,8 +269,8 @@ s3Connection c = do
 			warning $ "Set both " ++ s3AccessKey ++ " and " ++ s3SecretKey  ++ " to use S3"
 			return Nothing
 	where
-		host = fromJust $ (M.lookup "host" c)
-		port = let s = fromJust $ (M.lookup "port" c) in
+		host = fromJust $ M.lookup "host" c
+		port = let s = fromJust $ M.lookup "port" c in
 			case reads s of
 			[(p, _)] -> p
 			_ -> error $ "bad S3 port value: " ++ s
@@ -283,7 +281,7 @@ s3GetCreds :: RemoteConfig -> Annex (Maybe (String, String))
 s3GetCreds c = do
 	ak <- getEnvKey s3AccessKey
 	sk <- getEnvKey s3SecretKey
-	if (null ak || null sk)
+	if null ak || null sk
 		then do
 			mcipher <- remoteCipher c
 			case (M.lookup "s3creds" c, mcipher) of
@@ -291,9 +289,7 @@ s3GetCreds c = do
 					s <- liftIO $ withDecryptedContent cipher
 						(return $ L.pack $ fromB64 encrypted)
 						(return . L.unpack)
-					let line = lines s
-					let ak' = line !! 0
-					let sk' = line !! 1
+					let [ak', sk', _rest] = lines s
 					liftIO $ do
 						setEnv s3AccessKey ak True
 						setEnv s3SecretKey sk True
diff --git a/Remote/Special.hs b/Remote/Special.hs
index 9a00dbd82..d6f362ce3 100644
--- a/Remote/Special.hs
+++ b/Remote/Special.hs
@@ -38,7 +38,7 @@ gitConfigSpecialRemote u c k v = do
 	g <- Annex.gitRepo
 	liftIO $ do
 		Git.run g "config" [Param (configsetting $ "annex-"++k), Param v]
-		Git.run g "config" [Param (configsetting $ "annex-uuid"), Param u]
+		Git.run g "config" [Param (configsetting "annex-uuid"), Param u]
 	where
 		remotename = fromJust (M.lookup "name" c)
 		configsetting s = "remote." ++ remotename ++ "." ++ s
diff --git a/Remote/Ssh.hs b/Remote/Ssh.hs
index 0d4842a1a..fe4e6dfc1 100644
--- a/Remote/Ssh.hs
+++ b/Remote/Ssh.hs
@@ -39,7 +39,7 @@ git_annex_shell r command params
 	where
 		dir = Git.workTree r
 		shellcmd = "git-annex-shell"
-		shellopts = (Param command):(File dir):params
+		shellopts = Param command : File dir : params
 		sshcmd = shellcmd ++ " " ++ 
 			unwords (map shellEscape $ toCommand shellopts)
 
diff --git a/Remote/Web.hs b/Remote/Web.hs
index d3d140d73..60f64cfe0 100644
--- a/Remote/Web.hs
+++ b/Remote/Web.hs
@@ -52,7 +52,7 @@ webUUID = "00000000-0000-0000-0000-000000000001"
 
 gen :: Git.Repo -> UUID -> Maybe RemoteConfig -> Annex (Remote Annex)
 gen r _ _ = 
-	return $ Remote {
+	return Remote {
 		uuid = webUUID,
 		cost = expensiveRemoteCost,
 		name = Git.repoDescribe r,
@@ -111,7 +111,7 @@ checkKey' (u:us) = do
 	if e then return e else checkKey' us
 
 urlexists :: URLString -> IO Bool
-urlexists url = do
+urlexists url =
 	case parseURI url of
 		Nothing -> return False
 		Just u -> do
diff --git a/Touch.hsc b/Touch.hsc
index 4f26855d2..dd0c38984 100644
--- a/Touch.hsc
+++ b/Touch.hsc
@@ -15,6 +15,7 @@ module Touch (
 
 import Foreign
 import Foreign.C
+import Control.Monad (when)
 
 newtype TimeSpec = TimeSpec CTime
 
@@ -66,9 +67,7 @@ touchBoth file atime mtime follow =
 	withCString file $ \f -> do
 		pokeArray ptr [atime, mtime]
 		r <- c_utimensat at_fdcwd f ptr flags
-		if (r /= 0)
-			then throwErrno "touchBoth"
-			else return ()
+		when (r /= 0) $ throwErrno "touchBoth"
 	where
 		flags = if follow
 			then 0
diff --git a/Utility/CopyFile.hs b/Utility/CopyFile.hs
index 5ee4a91df..2e06dd92b 100644
--- a/Utility/CopyFile.hs
+++ b/Utility/CopyFile.hs
@@ -20,10 +20,8 @@ copyFile src dest = do
 		removeFile dest
 	boolSystem "cp" [params, File src, File dest]
 	where
-		params = if SysConfig.cp_reflink_auto
-			then Params "--reflink=auto"
-			else if SysConfig.cp_a
-				then Params "-a"
-				else if SysConfig.cp_p
-					then Params "-p"
-					else Params ""
+		params
+			| SysConfig.cp_reflink_auto = Params "--reflink=auto"
+			| SysConfig.cp_a = Params "-a"
+			| SysConfig.cp_p = Params "-p"
+			| otherwise = Params ""
diff --git a/Utility/DataUnits.hs b/Utility/DataUnits.hs
index 7af2eadaf..f2bc333ea 100644
--- a/Utility/DataUnits.hs
+++ b/Utility/DataUnits.hs
@@ -106,7 +106,7 @@ oldSchoolUnits = map mingle $ zip storageUnits memoryUnits
 {- approximate display of a particular number of bytes -}
 roughSize :: [Unit] -> Bool -> ByteSize -> String
 roughSize units abbrev i
-	| i < 0 = "-" ++ findUnit units' (negate i)
+	| i < 0 = '-' : findUnit units' (negate i)
 	| otherwise = findUnit units' i
 	where
 		units' = reverse $ sort units -- largest first
@@ -139,10 +139,10 @@ readSize :: [Unit] -> String -> Maybe ByteSize
 readSize units input
 	| null parsednum = Nothing
 	| null parsedunit = Nothing
-	| otherwise = Just $ round $ number * (fromIntegral multiplier)
+	| otherwise = Just $ round $ number * fromIntegral multiplier
 	where
 		(number, rest) = head parsednum
-		multiplier = head $ parsedunit
+		multiplier = head parsedunit
 		unitname = takeWhile isAlpha $ dropWhile isSpace rest
 
 		parsednum = reads input :: [(Double, String)]
diff --git a/Utility/Dot.hs b/Utility/Dot.hs
index 869684996..83f52a3cc 100644
--- a/Utility/Dot.hs
+++ b/Utility/Dot.hs
@@ -20,13 +20,13 @@ graphNode nodeid desc = label desc $ quote nodeid
 
 {- an edge between two nodes -}
 graphEdge :: String -> String -> Maybe String -> String
-graphEdge fromid toid desc = indent $ maybe edge (\d -> label d edge) desc
+graphEdge fromid toid desc = indent $ maybe edge (`label` edge) desc
 	where
 		edge = quote fromid ++ " -> " ++ quote toid
 
 {- adds a label to a node or edge -}
 label :: String -> String -> String
-label l s = attr "label" l s
+label = attr "label"
 
 {- adds an attribute to a node or edge
  - (can be called multiple times for multiple attributes) -}
@@ -35,7 +35,7 @@ attr a v s = s ++ " [ " ++ a ++ "=" ++ quote v ++ " ]"
 
 {- fills a node with a color -}
 fillColor :: String -> String -> String
-fillColor color s = attr "fillcolor" color $ attr "style" "filled" $ s
+fillColor color s = attr "fillcolor" color $ attr "style" "filled" s
 
 {- apply to graphNode to put the node in a labeled box -}
 subGraph :: String -> String -> String -> String -> String
@@ -52,10 +52,10 @@ subGraph subid l color s =
 		setlabel = "label=" ++ quote l
 		setfilled = "style=" ++ quote "filled"
 		setcolor = "fillcolor=" ++ quote color
-		ii x = (indent $ indent x) ++ "\n"
+		ii x = indent (indent x) ++ "\n"
 
 indent ::String -> String
-indent s = "\t" ++ s
+indent s = '\t' : s
 
 quote :: String -> String
 quote s = "\"" ++ s' ++ "\""
diff --git a/Utility/RsyncFile.hs b/Utility/RsyncFile.hs
index c68909d2d..6e21ba063 100644
--- a/Utility/RsyncFile.hs
+++ b/Utility/RsyncFile.hs
@@ -19,7 +19,7 @@ rsyncShell command = [Param "-e", Param $ unwords $ map escape (toCommand comman
 		{- rsync requires some weird, non-shell like quoting in
                  - here. A doubled single quote inside the single quoted
                  - string is a single quote. -}
-		escape s = "'" ++  (join "''" $ split "'" s) ++ "'"
+		escape s = "'" ++  join "''" (split "'" s) ++ "'"
 
 {- Runs rsync in server mode to send a file, and exits. -}
 rsyncServerSend :: FilePath -> IO ()