nukes another 15 lines thanks to ifM

Remote/Directory.hs

@@ -100,11 +100,7 @@ withCheckedFiles _ _ [] _ _ = return False
 withCheckedFiles check Nothing d k a = go $ locations d k
 	where
 		go [] = return False
-		go (f:fs) = do
-			use <- check f
-			if use
-				then a [f]
-				else go fs
+		go (f:fs) = ifM (check f) ( a [f] , go fs )
 withCheckedFiles check (Just _) d k a = go $ locations d k
 	where
 		go [] = return False
@@ -115,10 +111,8 @@ withCheckedFiles check (Just _) d k a = go $ locations d k
 				then do
 					count <- readcount chunkcount
 					let chunks = take count $ chunkStream f
-					ok <- all id <$> mapM check chunks
-					if ok
-						then a chunks
-						else return False
+					ifM (all id <$> mapM check chunks)
+						( a chunks , return False )
 				else go fs
 		readcount f = fromMaybe (error $ "cannot parse " ++ f)
 			. (readish :: String -> Maybe Int)

Remote/Git.hs

@@ -127,10 +127,11 @@ tryGitConfigRead r
 			Annex.changeState $ \s -> s { Annex.repo = g' }
 
 		exchange [] _ = []
-		exchange (old:ls) new =
-			if Git.remoteName old == Git.remoteName new
-				then new : exchange ls new
-				else old : exchange ls new
+		exchange (old:ls) new
+			| Git.remoteName old == Git.remoteName new =
+				new : exchange ls new
+			| otherwise =
+				old : exchange ls new
 
 {- Checks if a given remote has the content for a key inAnnex.
  - If the remote cannot be accessed, or if it cannot determine
@@ -227,11 +228,11 @@ copyFromRemoteCheap r key file
 	| not $ Git.repoIsUrl r = do
 		loc <- liftIO $ gitAnnexLocation key r
 		liftIO $ catchBoolIO $ createSymbolicLink loc file >> return True
-	| Git.repoIsSsh r = do
-		ok <- Annex.Content.preseedTmp key file
-		if ok
-			then copyFromRemote r key file
-			else return False
+	| Git.repoIsSsh r =
+		ifM (Annex.Content.preseedTmp key file)
+			( copyFromRemote r key file
+			, return False
+			)
 	| otherwise = return False
 
 {- Tries to copy a key's content to a remote's annex. -}
@@ -254,22 +255,24 @@ copyToRemote r key
 rsyncHelper :: [CommandParam] -> Annex Bool
 rsyncHelper p = do
 	showOutput -- make way for progress bar
-	res <- liftIO $ rsync p
-	if res
-		then return res
-		else do
+	ifM (liftIO $ rsync p)
+		( return True
+		, do
 			showLongNote "rsync failed -- run git annex again to resume file transfer"
-			return res
+			return False
+		)
 
 {- Copys a file with rsync unless both locations are on the same
  - filesystem. Then cp could be faster. -}
 rsyncOrCopyFile :: [CommandParam] -> FilePath -> FilePath -> Annex Bool
-rsyncOrCopyFile rsyncparams src dest = do
-	ss <- liftIO $ getFileStatus $ parentDir src
-	ds <- liftIO $ getFileStatus $ parentDir dest
-	if deviceID ss == deviceID ds
-		then liftIO $ copyFileExternal src dest
-		else rsyncHelper $ rsyncparams ++ [Param src, Param dest]
+rsyncOrCopyFile rsyncparams src dest =
+	ifM (sameDeviceIds src dest)
+		( liftIO $ copyFileExternal src dest
+		, rsyncHelper $ rsyncparams ++ [Param src, Param dest]
+		)
+	where
+		sameDeviceIds a b = (==) <$> (getDeviceId a) <*> (getDeviceId b)
+		getDeviceId f = deviceID <$> liftIO (getFileStatus $ parentDir f)
 
 {- Generates rsync parameters that ssh to the remote and asks it
  - to either receive or send the key's content. -}

Remote/Helper/Hooks.hs

@@ -84,10 +84,8 @@ runHooks r starthook stophook a = do
 			liftIO $ closeFd fd
 
 lookupHook :: Remote -> String -> Annex (Maybe String)
-lookupHook r n = do
-	command <- getConfig (repo r) hookname ""
-	if null command
-		then return Nothing
-		else return $ Just command
+lookupHook r n = go =<< getConfig (repo r) hookname ""
 	where
+		go "" = return Nothing
+		go command = return $ Just command
 		hookname =  n ++ "-command"

Remote/Hook.hs

@@ -89,13 +89,13 @@ runHook hooktype hook k f a = maybe (return False) run =<< lookupHook hooktype h
 	where
 		run command = do
 			showOutput -- make way for hook output
-			res <- liftIO $ boolSystemEnv
-				"sh" [Param "-c", Param command] $ hookEnv k f
-			if res
-				then a
-				else do
+			ifM (liftIO $ boolSystemEnv
+				"sh" [Param "-c", Param command] $ hookEnv k f)
+				( a
+				, do
 					warning $ hook ++ " hook exited nonzero!"
-					return res
+					return False
+				)
 
 store :: String -> Key -> Annex Bool
 store h k = do

Remote/Rsync.hs

@@ -113,20 +113,16 @@ retrieve o k f = untilTrue (rsyncUrls o k) $ \u -> rsyncRemote o
 	]
 
 retrieveCheap :: RsyncOpts -> Key -> FilePath -> Annex Bool
-retrieveCheap o k f = do
-	ok <- preseedTmp k f
-	if ok
-		then retrieve o k f
-		else return False
+retrieveCheap o k f = ifM (preseedTmp k f) ( retrieve o k f , return False )
 
 retrieveEncrypted :: RsyncOpts -> (Cipher, Key) -> Key -> FilePath -> Annex Bool
 retrieveEncrypted o (cipher, enck) _ f = withTmp enck $ \tmp -> do
-	res <- retrieve o enck tmp
-	if res
-		then liftIO $ catchBoolIO $ do
+	ifM (retrieve o enck tmp)
+		( liftIO $ catchBoolIO $ do
 			withDecryptedContent cipher (L.readFile tmp) $ L.writeFile f
 			return True
-		else return res
+		, return False
+		)
 
 remove :: RsyncOpts -> Key -> Annex Bool
 remove o k = withRsyncScratchDir $ \tmp -> liftIO $ do
@@ -188,12 +184,12 @@ withRsyncScratchDir a = do
 rsyncRemote :: RsyncOpts -> [CommandParam] -> Annex Bool
 rsyncRemote o params = do
 	showOutput -- make way for progress bar
-	res <- liftIO $ rsync $ rsyncOptions o ++ defaultParams ++ params
-	if res
-		then return res
-		else do
+	ifM (liftIO $ rsync $ rsyncOptions o ++ defaultParams ++ params)
+		( return True
+		, do
 			showLongNote "rsync failed -- run git annex again to resume file transfer"
-			return res
+			return False
+		)
 	where
 		defaultParams = [Params "--progress"]
 

Utility/Url.hs

@@ -14,15 +14,10 @@ module Utility.Url (
 	get
 ) where
 
-import Control.Applicative
-import Control.Monad
+import Common
 import qualified Network.Browser as Browser
 import Network.HTTP
 import Network.URI
-import Data.Maybe
-
-import Utility.SafeCommand
-import Utility.Path
 
 type URLString = String
 
@@ -47,7 +42,7 @@ exists url =
 				(2,_,_) -> return (True, size r)
 				_ -> return (False, Nothing)
 	where
-		size = liftM read . lookupHeader HdrContentLength . rspHeaders
+		size = liftM Prelude.read . lookupHeader HdrContentLength . rspHeaders
 
 canDownload :: IO Bool
 canDownload = (||) <$> inPath "wget" <*> inPath "curl"
@@ -60,20 +55,17 @@ canDownload = (||) <$> inPath "wget" <*> inPath "curl"
  - for only one in.
  -}
 download :: URLString -> [CommandParam] -> FilePath -> IO Bool
-download url options file = do
-	e <- inPath "wget"
-	if e
-		then
-			go "wget" [Params "-c -O", File file, File url]
-		else
-			-- Uses the -# progress display, because the normal
-			-- one is very confusing when resuming, showing
-			-- the remainder to download as the whole file,
-			-- and not indicating how much percent was
-			-- downloaded before the resume.
-			go "curl" [Params "-L -C - -# -o", File file, File url]
+download url options file = ifM (inPath "wget") (wget , curl)
 	where
-		go cmd opts = boolSystem cmd (options++opts)
+		wget = go "wget" [Params "-c -O"]
+		{- Uses the -# progress display, because the normal
+		 - one is very confusing when resuming, showing
+		 - the remainder to download as the whole file,
+		 - and not indicating how much percent was
+		 - downloaded before the resume. -}
+		curl = go "curl" [Params "-L -C - -# -o"]
+		go cmd opts = boolSystem cmd $
+			options++opts++[File file, File url]
 
 {- Downloads a small file. -}
 get :: URLString -> IO String