hlint refactorings

30 files changed, 109 insertions, 104 deletions

diff --git a/src/Actions.hs b/src/Actions.hs
index 5bcfea7..a739828 100644
--- a/src/Actions.hs
+++ b/src/Actions.hs
@@ -28,7 +28,7 @@ stripActions s = case matchRegex actionRegex s of
   Nothing -> s
   Just _  -> stripActions strippedOneLevel
   where
-      strippedOneLevel = subRegex actionRegex s $ "[action=\\1\\2]\\3[/action]"
+      strippedOneLevel = subRegex actionRegex s "[action=\\1\\2]\\3[/action]"
 
 actionRegex :: Regex
 actionRegex = mkRegex "<action=`?([^>`]*)`?( +button=[12345]+)?>(.+)</action>"
diff --git a/src/ColorCache.hs b/src/ColorCache.hs
index e9c5810..3f8d7b4 100644
--- a/src/ColorCache.hs
+++ b/src/ColorCache.hs
@@ -35,10 +35,10 @@ import Graphics.X11.Xlib
 data DynPixel = DynPixel Bool Pixel
 
 initColor :: Display -> String -> IO DynPixel
-initColor dpy c = handle black $ (initColor' dpy c)
+initColor dpy c = handle black $ initColor' dpy c
   where
     black :: SomeException -> IO DynPixel
-    black = (const . return $ DynPixel False (blackPixel dpy $ defaultScreen dpy))
+    black = const . return $ DynPixel False (blackPixel dpy $ defaultScreen dpy)
 
 type ColorCache = [(String, Color)]
 {-# NOINLINE colorCache #-}
diff --git a/src/IPC/DBus.hs b/src/IPC/DBus.hs
index b95e59f..3f2d6f2 100644
--- a/src/IPC/DBus.hs
+++ b/src/IPC/DBus.hs
@@ -44,7 +44,7 @@ runIPC mvst = handle printException exportConnection
 
 sendSignalMethod :: TMVar SignalType -> Method
 sendSignalMethod mvst = method interfaceName sendSignalName
-    (signature_ [variantType $ toVariant $ (undefined :: SignalType)])
+    (signature_ [variantType $ toVariant (undefined :: SignalType)])
     (signature_ [])
     sendSignalMethodCall
     where
diff --git a/src/Main.hs b/src/Main.hs
index 92573b9..f3885ff 100644
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -37,7 +37,7 @@ import System.Exit
 import System.Environment
 import System.FilePath ((</>))
 import System.Posix.Files
-import Control.Monad (unless)
+import Control.Monad (unless, liftM)
 
 import Signal (setupSignalHandler)
 
@@ -94,13 +94,13 @@ xdgConfigDir :: IO String
 xdgConfigDir = do env <- getEnvironment
                   case lookup "XDG_CONFIG_HOME" env of
                        Just val -> return val
-                       Nothing  -> getHomeDirectory >>= return . (</> ".config")
+                       Nothing  -> liftM (</> ".config") getHomeDirectory
 
 xmobarConfigDir :: IO FilePath
-xmobarConfigDir = xdgConfigDir >>= return . (</> "xmobar")
+xmobarConfigDir = liftM (</> "xmobar") xdgConfigDir
 
 getXdgConfigFile :: IO FilePath
-getXdgConfigFile = xmobarConfigDir >>= return . (</> "xmobarrc")
+getXdgConfigFile = liftM (</> "xmobarrc") xmobarConfigDir
 
 -- | Read default configuration file or load the default config
 readDefaultConfig :: IO (Config,[String])
diff --git a/src/Parsers.hs b/src/Parsers.hs
index cda7004..69c5f21 100644
--- a/src/Parsers.hs
+++ b/src/Parsers.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE FlexibleContexts, GeneralizedNewtypeDeriving #-}
+{-# LANGUAGE FlexibleContexts #-}
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Xmobar.Parsers
@@ -87,7 +87,7 @@ rawParser c a = do
   char ':'
   case reads lenstr of
     [(len,[])] -> do
-      guard ((len :: Integer) <= (fromIntegral (maxBound :: Int)))
+      guard ((len :: Integer) <= fromIntegral (maxBound :: Int))
       s <- count (fromIntegral len) anyChar
       string "/>"
       return [(Text s, c, a)]
@@ -123,7 +123,7 @@ actionParser c act = do
   return (concat s)
 
 toButtons :: String -> [Button]
-toButtons s = map (\x -> read [x]) s
+toButtons = map (\x -> read [x])
 
 -- | Parsers a string wrapped in a color specification.
 colorParser :: Maybe [Action] -> Parser [(Widget, ColorString, Maybe [Action])]
diff --git a/src/Plugins/BufferedPipeReader.hs b/src/Plugins/BufferedPipeReader.hs
index a2ea2a3..9a7266e 100644
--- a/src/Plugins/BufferedPipeReader.hs
+++ b/src/Plugins/BufferedPipeReader.hs
@@ -14,7 +14,7 @@
 
 module Plugins.BufferedPipeReader where
 
-import Control.Monad(forM_, when)
+import Control.Monad(forM_, when, void)
 import Control.Concurrent
 import Control.Concurrent.STM
 import System.IO
@@ -66,7 +66,7 @@ instance Exec BufferedPipeReader where
 
             where
             sfork :: IO () -> IO ()
-            sfork f = forkIO f >> return ()
+            sfork f = void (forkIO f)
 
             update :: IO (Int, Bool, String, TVar Bool)
             update = atomically $ do
diff --git a/src/Plugins/Date.hs b/src/Plugins/Date.hs
index 3caad30..a263536 100644
--- a/src/Plugins/Date.hs
+++ b/src/Plugins/Date.hs
@@ -21,6 +21,7 @@ module Plugins.Date (Date(..)) where
 import Plugins
 
 import System.Locale
+import Control.Monad (liftM)
 import Data.Time
 
 data Date = Date String String Int
@@ -32,4 +33,4 @@ instance Exec Date where
     rate  (Date _ _ r) = r
 
 date :: String -> IO String
-date format = getZonedTime >>= return . formatTime defaultTimeLocale format
+date format = liftM (formatTime defaultTimeLocale format) getZonedTime
diff --git a/src/Plugins/EWMH.hs b/src/Plugins/EWMH.hs
index d5b70cb..5f1c0c4 100644
--- a/src/Plugins/EWMH.hs
+++ b/src/Plugins/EWMH.hs
@@ -1,5 +1,5 @@
 {-# OPTIONS_GHC -w #-}
-{-# LANGUAGE CPP, RecordWildCards, NamedFieldPuns, GeneralizedNewtypeDeriving #-}
+{-# LANGUAGE CPP, NamedFieldPuns, GeneralizedNewtypeDeriving #-}
 
 -----------------------------------------------------------------------------
 -- |
@@ -58,7 +58,7 @@ instance Exec EWMH where
             liftIO $ nextEvent' d ep
             e <- liftIO $ getEvent ep
             case e of
-                PropertyEvent { ev_atom = a, ev_window = w } -> do
+                PropertyEvent { ev_atom = a, ev_window = w } ->
                     case lookup a handlers' of
                         Just f -> f w
                         _      -> return ()
@@ -95,7 +95,7 @@ fmt e (Workspaces opts) = sep " "
     attrs = [(n, [s | (s, b) <- stats i, b]) | (i, n) <- zip [0 ..] (desktopNames e)]
     nonEmptys = Set.unions . map desktops . Map.elems $ clients e
 
-modifier :: Modifier -> (String -> String)
+modifier :: Modifier -> String -> String
 modifier Hide = const ""
 modifier (Color fg bg) = \x -> concat ["<fc=", fg, if null bg then "" else "," ++ bg
                                       , ">", x, "</fc>"]
@@ -227,9 +227,9 @@ updateClientList _ = do
                         dels = Map.difference cl cl'
                         new = Map.difference cl' cl
                     modify (\s -> s { clients = Map.union (Map.intersection cl cl') cl'})
-                    mapM_ unmanage (map fst $ Map.toList dels)
-                    mapM_ listen (map fst $ Map.toList cl')
-                    mapM_ update (map fst $ Map.toList new)
+                    mapM_ (unmanage . fst) (Map.toList dels)
+                    mapM_ (listen . fst)   (Map.toList cl')
+                    mapM_ (update . fst)   (Map.toList new)
         _       -> return ()
  where
     unmanage w = asks display >>= \d -> liftIO $ selectInput d w 0
diff --git a/src/Plugins/MBox.hs b/src/Plugins/MBox.hs
index d9a9765..62f9d78 100644
--- a/src/Plugins/MBox.hs
+++ b/src/Plugins/MBox.hs
@@ -71,7 +71,7 @@ data MBox = MBox [(String, FilePath, String)] [String] String
 instance Exec MBox where
   alias (MBox _ _ a) = a
 #ifndef INOTIFY
-  start _ _ = do
+  start _ _ =
     hPutStrLn stderr $ "Warning: xmobar is not compiled with -fwith_inotify" ++
           " but the MBox plugin requires it"
 #else
diff --git a/src/Plugins/Mail.hs b/src/Plugins/Mail.hs
index 23a5654..772d1d7 100644
--- a/src/Plugins/Mail.hs
+++ b/src/Plugins/Mail.hs
@@ -41,7 +41,7 @@ data Mail = Mail [(String, FilePath)] String
 instance Exec Mail where
     alias (Mail _ a) = a
 #ifndef INOTIFY
-    start _ _ = do
+    start _ _ =
         hPutStrLn stderr $ "Warning: xmobar is not compiled with -fwith_inotify,"
                         ++ " but the Mail plugin requires it."
 #else
diff --git a/src/Plugins/Monitors.hs b/src/Plugins/Monitors.hs
index 860da71..9aef386 100644
--- a/src/Plugins/Monitors.hs
+++ b/src/Plugins/Monitors.hs
@@ -118,7 +118,7 @@ instance Exec Monitors where
     alias (DiskU _ _ _) = "disku"
     alias (DiskIO _ _ _) = "diskio"
     alias (Uptime _ _) = "uptime"
-    alias (CatInt n _ _ _) = "cat" ++ (show n)
+    alias (CatInt n _ _ _) = "cat" ++ show n
 #ifdef IWLIB
     alias (Wireless i _ _) = i ++ "wi"
 #endif
diff --git a/src/Plugins/Monitors/Batt.hs b/src/Plugins/Monitors/Batt.hs
index 3eb2051..ac8cb24 100644
--- a/src/Plugins/Monitors/Batt.hs
+++ b/src/Plugins/Monitors/Batt.hs
@@ -105,7 +105,7 @@ batteryFiles bat =
   do is_charge <- exists "charge_now"
      is_energy <- if is_charge then return False else exists "energy_now"
      is_power <- exists "power_now"
-     plain <- if is_charge then exists "charge_full" else exists "energy_full"
+     plain <- exists (if is_charge then "charge_full" else "energy_full")
      let cf = if is_power then "power_now" else "current_now"
          sf = if plain then "" else "_design"
      return $ case (is_charge, is_energy) of
@@ -150,8 +150,9 @@ readBatteries opts bfs =
            time = if idle then 0 else sum $ map time' bats
            mwatts = if idle then 1 else sign * watts
            time' b = (if ac then full b - now b else now b) / mwatts
-           acstr = if idle then idleString opts else
-                     if ac then onString opts else offString opts
+           acstr | idle      = idleString opts
+                 | ac        = onString opts
+                 | otherwise = offString opts
        return $ if isNaN left then NA else Result left watts time acstr
 
 runBatt :: [String] -> Monitor String
diff --git a/src/Plugins/Monitors/Bright.hs b/src/Plugins/Monitors/Bright.hs
index 1c4cc01..d29c5a4 100644
--- a/src/Plugins/Monitors/Bright.hs
+++ b/src/Plugins/Monitors/Bright.hs
@@ -14,6 +14,7 @@
 
 module Plugins.Monitors.Bright (brightConfig, runBright) where
 
+import Control.Applicative ((<$>))
 import Control.Exception (SomeException, handle)
 import qualified Data.ByteString.Lazy.Char8 as B
 import System.FilePath ((</>))
@@ -60,12 +61,12 @@ data Files = Files { fCurr :: String
 
 brightFiles :: BrightOpts -> IO Files
 brightFiles opts = do
-  is_curr <- fileExist $ (fCurr files)
-  is_max  <- fileExist $ (fCurr files)
-  if is_curr && is_max then return files else return NoFiles
-  where prefix = sysDir </> (subDir opts)
-        files = Files { fCurr = prefix </> (currBright opts)
-                      , fMax = prefix </> (maxBright opts)
+  is_curr <- fileExist $ fCurr files
+  is_max  <- fileExist $ fCurr files
+  return (if is_curr && is_max then files else NoFiles)
+  where prefix = sysDir </> subDir opts
+        files = Files { fCurr = prefix </> currBright opts
+                      , fMax = prefix </> maxBright opts
                       }
 
 runBright :: [String] ->  Monitor String
@@ -85,9 +86,9 @@ runBright args = do
 readBright :: Files -> IO Float
 readBright NoFiles = return 0
 readBright files = do
-  currVal<- grab $ (fCurr files)
-  maxVal <- grab $ (fMax files)
-  return $ (currVal / maxVal)
-  where grab f = handle handler (fmap (read . B.unpack) $ B.readFile f)
+  currVal<- grab $ fCurr files
+  maxVal <- grab $ fMax files
+  return (currVal / maxVal)
+  where grab f = handle handler (read . B.unpack <$> B.readFile f)
         handler = const (return 0) :: SomeException -> IO Float
 
diff --git a/src/Plugins/Monitors/CatInt.hs b/src/Plugins/Monitors/CatInt.hs
index 3d19270..aacbd71 100644
--- a/src/Plugins/Monitors/CatInt.hs
+++ b/src/Plugins/Monitors/CatInt.hs
@@ -20,6 +20,6 @@ catIntConfig = mkMConfig "<v>" ["v"]
 
 runCatInt :: FilePath -> [String] -> Monitor String
 runCatInt p _ =
-  let failureMessage = "Cannot read: " ++ (show p)
+  let failureMessage = "Cannot read: " ++ show p
       fmt x = show (truncate x :: Int)
   in  checkedDataRetrieval failureMessage [[p]] Nothing id fmt
diff --git a/src/Plugins/Monitors/Common.hs b/src/Plugins/Monitors/Common.hs
index 70f1b5f..1fd09a6 100644
--- a/src/Plugins/Monitors/Common.hs
+++ b/src/Plugins/Monitors/Common.hs
@@ -60,6 +60,7 @@ module Plugins.Monitors.Common (
                        ) where
 
 
+import Control.Applicative ((<$>))
 import Control.Monad.Reader
 import qualified Data.ByteString.Lazy.Char8 as B
 import Data.IORef
@@ -112,7 +113,7 @@ mods s m =
 
 setConfigValue :: a -> Selector a -> Monitor ()
 setConfigValue v s =
-       mods s (\_ -> v)
+       mods s (const v)
 
 getConfigValue :: Selector a -> Monitor a
 getConfigValue = sel
@@ -342,7 +343,7 @@ combine m ((s,ts,ss):xs) =
     do next <- combine m xs
        str <- case Map.lookup ts m of
          Nothing -> return $ "<" ++ ts ++ ">"
-         Just  r -> let f "" = r; f n = n; in fmap f $ parseTemplate' r m
+         Just  r -> let f "" = r; f n = n; in f <$> parseTemplate' r m
        return $ s ++ str ++ ss ++ next
 
 -- $strings
@@ -459,7 +460,7 @@ showVerticalBar v x = colorizeString v [convert $ 100 * x]
           | t <= 9600 = ' '
           | t > 9608 = chr 9608
           | otherwise = chr t
-          where t = 9600 + ((round val) `div` 12)
+          where t = 9600 + (round val `div` 12)
 
 showLogBar :: Float -> Float -> Monitor String
 showLogBar f v = do
diff --git a/src/Plugins/Monitors/CoreTemp.hs b/src/Plugins/Monitors/CoreTemp.hs
index bfe9aca..e19baf0 100644
--- a/src/Plugins/Monitors/CoreTemp.hs
+++ b/src/Plugins/Monitors/CoreTemp.hs
@@ -27,8 +27,8 @@ import Data.Char (isDigit)
 coreTempConfig :: IO MConfig
 coreTempConfig = mkMConfig
        "Temp: <core0>C" -- template
-       (zipWith (++) (repeat "core") (map show [0 :: Int ..])) -- available
-                                                               -- replacements
+       (map ((++) "core" . show) [0 :: Int ..]) -- available
+                                                -- replacements
 
 -- |
 -- Function retrieves monitor string holding the core temperature
@@ -39,7 +39,7 @@ runCoreTemp _ = do
    failureMessage <- getConfigValue naString
    let path = ["/sys/bus/platform/devices/coretemp.", "/temp", "_input"]
        path' = ["/sys/bus/platform/devices/coretemp.", "/hwmon/hwmon", "/temp", "_input"]
-       lbl  = Just ("_label", read . (dropWhile (not . isDigit)))
+       lbl  = Just ("_label", read . dropWhile (not . isDigit))
        divisor = 1e3 :: Double
        show' = showDigits (max 0 dn)
    checkedDataRetrieval failureMessage [path, path'] lbl (/divisor) show'
diff --git a/src/Plugins/Monitors/Cpu.hs b/src/Plugins/Monitors/Cpu.hs
index df2dc4e..10d945f 100644
--- a/src/Plugins/Monitors/Cpu.hs
+++ b/src/Plugins/Monitors/Cpu.hs
@@ -38,8 +38,8 @@ parseCpu cref =
        b <- cpuData
        writeIORef cref b
        let dif = zipWith (-) b a
-           tot = fromIntegral $ foldr (+) 0 dif
-           percent = map (/ tot) (map fromIntegral dif)
+           tot = fromIntegral $ sum dif
+           percent = map ((/ tot) . fromIntegral) dif
        return percent
 
 formatCpu :: [Float] -> Monitor [String]
diff --git a/src/Plugins/Monitors/CpuFreq.hs b/src/Plugins/Monitors/CpuFreq.hs
index 3fe2577..d3ecf89 100644
--- a/src/Plugins/Monitors/CpuFreq.hs
+++ b/src/Plugins/Monitors/CpuFreq.hs
@@ -24,8 +24,8 @@ import Plugins.Monitors.CoreCommon
 cpuFreqConfig :: IO MConfig
 cpuFreqConfig = mkMConfig
        "Freq: <cpu0>" -- template
-       (zipWith (++) (repeat "cpu") (map show [0 :: Int ..])) -- available
-                                                              -- replacements
+       (map ((++) "cpu" . show) [0 :: Int ..]) -- available
+                                             -- replacements
 
 -- |
 -- Function retrieves monitor string holding the cpu frequency (or frequencies)
@@ -33,7 +33,7 @@ runCpuFreq :: [String] -> Monitor String
 runCpuFreq _ = do
   let path = ["/sys/devices/system/cpu/cpu", "/cpufreq/scaling_cur_freq"]
       divisor = 1e6 :: Double
-      fmt x | x < 1 = (show (round (x * 1000) :: Integer)) ++ "MHz"
-            | otherwise = (show x) ++ "GHz"
+      fmt x | x < 1 = show (round (x * 1000) :: Integer) ++ "MHz"
+            | otherwise = show x ++ "GHz"
   failureMessage <- getConfigValue naString
   checkedDataRetrieval failureMessage [path] Nothing (/divisor) fmt
diff --git a/src/Plugins/Monitors/Disk.hs b/src/Plugins/Monitors/Disk.hs
index e0a7886..4cc2865 100644
--- a/src/Plugins/Monitors/Disk.hs
+++ b/src/Plugins/Monitors/Disk.hs
@@ -63,10 +63,10 @@ diskDevices req = do
   s <- B.readFile "/proc/diskstats"
   parse `fmap` mapM canon (devs s)
   where
-    canon (d, p) = do {d' <- canonicalizePath (d); return (d', p)}
+    canon (d, p) = do {d' <- canonicalizePath d; return (d', p)}
     devs = map (third . B.words) . B.lines
     parse = map undev . filter isReq
-    third (_:_:c:_) = ("/dev/" ++ (B.unpack c), B.unpack c)
+    third (_:_:c:_) = ("/dev/" ++ B.unpack c, B.unpack c)
     third _ = ("", "")
     isReq (d, p) = p `elem` req || drop 5 d `elem` req
     undev (d, f) = (drop 5 d, f)
diff --git a/src/Plugins/Monitors/Mem.hs b/src/Plugins/Monitors/Mem.hs
index e409095..db2e5de 100644
--- a/src/Plugins/Monitors/Mem.hs
+++ b/src/Plugins/Monitors/Mem.hs
@@ -30,10 +30,10 @@ parseMEM :: IO [Float]
 parseMEM =
     do file <- fileMEM
        let content = map words $ take 8 $ lines file
-           info = M.fromList $ map (\line -> (line !! 0, (read $ line !! 1 :: Float) / 1024)) content
+           info = M.fromList $ map (\line -> (head line, (read $ line !! 1 :: Float) / 1024)) content
            [total, free, buffer, cache] = map (info M.!) ["MemTotal:", "MemFree:", "Buffers:", "Cached:"]
            rest = free + buffer + cache
-           used = total - (M.findWithDefault rest "MemAvailable:" info)
+           used = total - M.findWithDefault rest "MemAvailable:" info
            usedratio = used / total
            freeratio = free / total
        return [usedratio, freeratio, total, free, buffer, cache, rest, used, freeratio]
diff --git a/src/Plugins/Monitors/Mpris.hs b/src/Plugins/Monitors/Mpris.hs
index 98b4c0f..245c0df 100644
--- a/src/Plugins/Monitors/Mpris.hs
+++ b/src/Plugins/Monitors/Mpris.hs
@@ -25,6 +25,7 @@ import Text.Printf (printf)
 import DBus
 import qualified DBus.Client as DC
 
+import Control.Arrow ((***))
 import Data.Maybe ( fromJust )
 import Data.Int ( Int32, Int64 )
 import System.IO.Unsafe (unsafePerformIO)
@@ -43,10 +44,10 @@ instance MprisVersion MprisVersion1 where
         { methodCallDestination = Just busName
         }
         where
-        busName       = busName_       $ "org.mpris." ++ p
-        objectPath    = objectPath_    $ "/Player"
-        interfaceName = interfaceName_ $ "org.freedesktop.MediaPlayer"
-        memberName    = memberName_    $ "GetMetadata"
+        busName       = busName_     $ "org.mpris." ++ p
+        objectPath    = objectPath_    "/Player"
+        interfaceName = interfaceName_ "org.freedesktop.MediaPlayer"
+        memberName    = memberName_    "GetMetadata"
 
     fieldsList MprisVersion1 = [ "album", "artist", "arturl", "mtime", "title"
                                , "tracknumber" ]
@@ -58,10 +59,10 @@ instance MprisVersion MprisVersion2 where
         , methodCallBody = arguments
         }
         where
-        busName       = busName_       $ "org.mpris.MediaPlayer2." ++ p
-        objectPath    = objectPath_    $ "/org/mpris/MediaPlayer2"
-        interfaceName = interfaceName_ $ "org.freedesktop.DBus.Properties"
-        memberName    = memberName_    $ "Get"
+        busName       = busName_     $ "org.mpris.MediaPlayer2." ++ p
+        objectPath    = objectPath_    "/org/mpris/MediaPlayer2"
+        interfaceName = interfaceName_ "org.freedesktop.DBus.Properties"
+        memberName    = memberName_    "Get"
         arguments     = map (toVariant::String -> Variant)
                             ["org.mpris.MediaPlayer2.Player", "Metadata"]
 
@@ -98,7 +99,7 @@ fromVar = fromJust . fromVariant
 
 unpackMetadata :: [Variant] -> [(String, Variant)]
 unpackMetadata [] = []
-unpackMetadata xs = ((map (\(k, v) -> (fromVar k, fromVar v))) . unpack . head) xs where
+unpackMetadata xs = (map (fromVar *** fromVar) . unpack . head) xs where
                       unpack v = case variantType v of
                             TypeDictionary _ _ -> dictionaryItems $ fromVar v
                             TypeVariant -> unpack $ fromVar v
diff --git a/src/Plugins/Monitors/MultiCpu.hs b/src/Plugins/Monitors/MultiCpu.hs
index 429c38a..150fb7e 100644
--- a/src/Plugins/Monitors/MultiCpu.hs
+++ b/src/Plugins/Monitors/MultiCpu.hs
@@ -15,6 +15,7 @@
 module Plugins.Monitors.MultiCpu (startMultiCpu) where
 
 import Plugins.Monitors.Common
+import Control.Applicative ((<$>))
 import qualified Data.ByteString.Lazy.Char8 as B
 import Data.List (isPrefixOf, transpose, unfoldr)
 import Data.IORef (IORef, newIORef, readIORef, writeIORef)
@@ -52,16 +53,16 @@ parseCpuData cref =
 percent :: [Float] -> [Float] -> [Float]
 percent b a = if tot > 0 then map (/ tot) $ take 4 dif else [0, 0, 0, 0]
   where dif = zipWith (-) b a
-        tot = foldr (+) 0 dif
+        tot = sum dif
 
 formatMultiCpus :: [[Float]] -> Monitor [String]
 formatMultiCpus [] = return []
-formatMultiCpus xs = fmap concat $ mapM formatCpu xs
+formatMultiCpus xs = concat <$> mapM formatCpu xs
 
 formatCpu :: [Float] -> Monitor [String]
 formatCpu xs
   | length xs < 4 = showPercentsWithColors $ replicate vNum 0.0
-  | otherwise = let t = foldr (+) 0 $ take 3 xs
+  | otherwise = let t = sum $ take 3 xs
                 in do b <- showPercentBar (100 * t) t
                       h <- showVerticalBar (100 * t) t
                       ps <- showPercentsWithColors (t:xs)
diff --git a/src/Plugins/Monitors/Net.hs b/src/Plugins/Monitors/Net.hs
index 31dc411..39bdd61 100644
--- a/src/Plugins/Monitors/Net.hs
+++ b/src/Plugins/Monitors/Net.hs
@@ -22,7 +22,7 @@ import Plugins.Monitors.Common
 
 import Data.IORef (IORef, newIORef, readIORef, writeIORef)
 import Data.Time.Clock (UTCTime, getCurrentTime, diffUTCTime)
-import Control.Monad (forM, filterM)
+import Control.Monad (forM, filterM, liftM)
 import System.Directory (getDirectoryContents, doesFileExist)
 import System.FilePath ((</>))
 
@@ -147,11 +147,11 @@ runNet :: NetDevRef -> String -> [String] -> Monitor String
 runNet nref i _ = io (parseNet nref i) >>= printNet
 
 parseNets :: [(NetDevRef, String)] -> IO [NetDev]
-parseNets = mapM $ \(ref, i) -> parseNet ref i
+parseNets = mapM $ uncurry parseNet
 
 runNets :: [(NetDevRef, String)] -> [String] -> Monitor String
 runNets refs _ = io (parseActive refs) >>= printNet
-    where parseActive refs' = parseNets refs' >>= return . selectActive
+    where parseActive refs' = liftM selectActive (parseNets refs') 
           selectActive = maximum
 
 startNet :: String -> [String] -> Int -> (String -> IO ()) -> IO ()
diff --git a/src/Plugins/Monitors/Swap.hs b/src/Plugins/Monitors/Swap.hs
index 107eb1e..b6c5019 100644
--- a/src/Plugins/Monitors/Swap.hs
+++ b/src/Plugins/Monitors/Swap.hs
@@ -33,8 +33,8 @@ parseMEM =
                | l /= [] = head l !! i
                | otherwise = B.empty
            fs s l
-               | l == []    = False
-               | otherwise  = head l == B.pack s
+               | null l    = False
+               | otherwise = head l == B.pack s
            get_data s = flip (/) 1024 . read . B.unpack . li 1 . filter (fs s)
            st   = map B.words . B.lines $ file
            tot  = get_data "SwapTotal:" st
diff --git a/src/Plugins/Monitors/Thermal.hs b/src/Plugins/Monitors/Thermal.hs
index a3ffe6d..6013511 100644
--- a/src/Plugins/Monitors/Thermal.hs
+++ b/src/Plugins/Monitors/Thermal.hs
@@ -14,6 +14,7 @@
 
 module Plugins.Monitors.Thermal where
 
+import Control.Monad (liftM)
 import qualified Data.ByteString.Lazy.Char8 as B
 import Plugins.Monitors.Common
 import System.Posix.Files (fileExist)
@@ -32,11 +33,9 @@ runThermal args = do
     let zone = head args
         file = "/proc/acpi/thermal_zone/" ++ zone ++ "/temperature"
     exists <- io $ fileExist file
-    case exists of
-         False  -> return $ "Thermal (" ++ zone ++ "): N/A"
-         True   -> do number <- io $ B.readFile file
-                                     >>= return . (read :: String -> Int)
-                                                . stringParser (1, 0)
-                      thermal <- showWithColors show number
-                      parseTemplate [  thermal ]
+    if exists
+        then do number <- io $ liftM ((read :: String -> Int) . stringParser (1, 0)) (B.readFile file)
+                thermal <- showWithColors show number
+                parseTemplate [  thermal ]
+        else return $ "Thermal (" ++ zone ++ "): N/A"
 
diff --git a/src/Plugins/Monitors/Weather.hs b/src/Plugins/Monitors/Weather.hs
index dfc421e..ba4d911 100644
--- a/src/Plugins/Monitors/Weather.hs
+++ b/src/Plugins/Monitors/Weather.hs
@@ -68,7 +68,7 @@ pTime = do y <- getNumbersAsString
            char ' '
            (h:hh:mi:mimi) <- getNumbersAsString
            char ' '
-           return (y, m, d ,([h]++[hh]++":"++[mi]++mimi))
+           return (y, m, d ,[h]++[hh]++":"++[mi]++mimi)
 
 pTemp :: Parser (Int, Int)
 pTemp = do let num = digit <|> char '-' <|> char '.'
@@ -76,10 +76,10 @@ pTemp = do let num = digit <|> char '-' <|> char '.'
            manyTill anyChar $ char '('
            c <- manyTill num $ char ' '
            skipRestOfLine
-           return $ (floor (read c :: Double), floor (read f :: Double))
+           return (floor (read c :: Double), floor (read f :: Double))
 
 pRh :: Parser Int
-pRh = do s <- manyTill digit $ (char '%' <|> char '.')
+pRh = do s <- manyTill digit (char '%' <|> char '.')
          return $ read s
 
 pPressure :: Parser Int
@@ -123,7 +123,7 @@ parseData =
        skipTillString "Pressure (altimeter): "
        p <- pPressure
        manyTill skipRestOfLine eof
-       return $ [WI st ss y m d h w v sk tC tF dp rh p]
+       return [WI st ss y m d h w v sk tC tF dp rh p]
 
 defUrl :: String
 defUrl = "http://weather.noaa.gov/pub/data/observations/metar/decoded/"
@@ -139,7 +139,7 @@ getData station = do
           errHandler _ = return "<Could not retrieve data>"
 
 formatWeather :: [WeatherInfo] -> Monitor String
-formatWeather [(WI st ss y m d h w v sk tC tF dp r p)] =
+formatWeather [WI st ss y m d h w v sk tC tF dp r p] =
     do cel <- showWithColors show tC
        far <- showWithColors show tF
        parseTemplate [st, ss, y, m, d, h, w, v, sk, cel, far, dp, show r , show p ]
@@ -158,10 +158,10 @@ weatherReady str = do
     io $ CE.catch (simpleHTTP request >>= checkResult) errHandler
     where errHandler :: CE.IOException -> IO Bool
           errHandler _ = return False
-          checkResult result = do
+          checkResult result =
             case result of
                 Left _ -> return False
-                Right response -> do
+                Right response ->
                     case rspCode response of
                         -- Permission or network errors are failures; anything
                         -- else is recoverable.
diff --git a/src/Plugins/PipeReader.hs b/src/Plugins/PipeReader.hs
index 7efea60..058ed46 100644
--- a/src/Plugins/PipeReader.hs
+++ b/src/Plugins/PipeReader.hs
@@ -19,7 +19,7 @@ import Plugins
 import System.Posix.Files
 import Control.Concurrent(threadDelay)
 import Control.Exception
-import Control.Monad(when)
+import Control.Monad(forever, unless)
 
 data PipeReader = PipeReader String String
     deriving (Read, Show)
@@ -28,21 +28,18 @@ instance Exec PipeReader where
     alias (PipeReader _ a)    = a
     start (PipeReader p _) cb = do
         let (def, pipe) = split ':' p
-        when (not $ null def) (cb def)
+        unless (null def) (cb def)
         checkPipe pipe
         h <- openFile pipe ReadWriteMode
         forever (hGetLineSafe h >>= cb)
       where
-        forever a = a >> forever a
-        split c xs | c `elem` xs = let (pre, post) = span ((/=) c) xs
-                                   in (pre, dropWhile ((==) c) post)
+        split c xs | c `elem` xs = let (pre, post) = span (c /=) xs
+                                   in (pre, dropWhile (c ==) post)
                    | otherwise   = ([], xs)
 
 checkPipe :: FilePath -> IO ()
-checkPipe file = do
+checkPipe file =
     handle (\(SomeException _) -> waitForPipe) $ do
-    status <- getFileStatus file
-    if isNamedPipe status
-      then return ()
-      else waitForPipe
+        status <- getFileStatus file
+        unless (isNamedPipe status) waitForPipe
     where waitForPipe = threadDelay 1000 >> checkPipe file
diff --git a/src/Plugins/StdinReader.hs b/src/Plugins/StdinReader.hs
index 35f0375..31d041e 100644
--- a/src/Plugins/StdinReader.hs
+++ b/src/Plugins/StdinReader.hs
@@ -34,7 +34,7 @@ instance Exec StdinReader where
     s <- handle (\(SomeException e) -> do hPrint stderr e; return "")
                 (hGetLineSafe stdin)
     cb $ escape stdinReader s
-    eof <- hIsEOF stdin
+    eof <- isEOF
     if eof
       then exitImmediately ExitSuccess
       else start stdinReader cb
diff --git a/src/Window.hs b/src/Window.hs
index 876b7a2..f7e1801 100644
--- a/src/Window.hs
+++ b/src/Window.hs
@@ -16,6 +16,7 @@
 module Window where
 
 import Prelude
+import Control.Applicative ((<$>))
 import Control.Monad (when, unless)
 import Graphics.X11.Xlib hiding (textExtents, textWidth)
 import Graphics.X11.Xlib.Extras
@@ -190,5 +191,5 @@ showWindow r c d w = do
     sync d False
 
 isMapped :: Display -> Window -> IO Bool
-isMapped d w = fmap ism $ getWindowAttributes d w
+isMapped d w = ism <$> getWindowAttributes d w
     where ism (WindowAttributes { wa_map_state = wms }) = wms /= waIsUnmapped
diff --git a/src/Xmobar.hs b/src/Xmobar.hs
index c126b7c..6ea8fab 100644
--- a/src/Xmobar.hs
+++ b/src/Xmobar.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE DeriveDataTypeable, CPP #-}
+{-# LANGUAGE CPP #-}
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Xmobar
@@ -36,13 +36,14 @@ import Graphics.X11.Xinerama
 import Graphics.X11.Xrandr
 
 import Control.Arrow ((&&&))
+import Control.Applicative ((<$>))
 import Control.Monad.Reader
 import Control.Concurrent
 import Control.Concurrent.STM
 import Control.Exception (handle, SomeException(..))
 import Data.Bits
 import Data.Map hiding (foldr, map, filter)
-import Data.Maybe (fromJust)
+import Data.Maybe (fromJust, isJust)
 
 import Bitmap
 import Config
@@ -204,10 +205,11 @@ eventLoop tv xc@(XConf d r w fs is cfg) as signal = do
           case position ocfg of
             OnScreen n o -> do
               srs <- getScreenInfo d
-              if n == length srs then
-                  return (ocfg {position = OnScreen 1 o})
-                else
-                  return (ocfg {position = OnScreen (n+1) o})
+              return (if n == length srs
+                       then
+                        (ocfg {position = OnScreen 1 o})
+                       else
+                        (ocfg {position = OnScreen (n+1) o}))
             o ->
               return (ocfg {position = OnScreen 1 o})
 
@@ -254,7 +256,7 @@ updateActions conf (Rectangle _ _ wid _) ~[left,center,right] = do
       getCoords (Text s,_,a) = textWidth d fs s >>= \tw -> return (a, 0, fi tw)
       getCoords (Icon s,_,a) = return (a, 0, fi $ iconW s)
       partCoord off xs = map (\(a, x, x') -> (fromJust a, x, x')) $
-                         filter (\(a, _,_) -> a /= Nothing) $
+                         filter (\(a, _,_) -> isJust a) $
                          scanl (\(_,_,x') (a,_,w') -> (a, x', x' + w')) (Nothing, 0, off) xs
 
       totSLen              = foldr (\(_,_,len) -> (+) len) 0
@@ -265,7 +267,7 @@ updateActions conf (Rectangle _ _ wid _) ~[left,center,right] = do
                                R -> remWidth xs
                                L -> offs
 
-  fmap concat $ mapM (\(a,xs) -> fmap (\xs' -> partCoord (offset a xs') xs') $ strLn xs) $
+  fmap concat $ mapM (\(a,xs) -> (\xs' -> partCoord (offset a xs') xs') <$> strLn xs) $
                 zip [L,C,R] [left,center,right]
 
 -- $print