Clean up here and there

Signed-off-by: Alexander Berntsen <alexander@plaimi.net>

Distribution/Gentoo/GHC.hs

@@ -119,7 +119,7 @@ readConf = ghcLibDir >>= confFiles >>= foldM addConf Map.empty
 -- Add this .conf file to the Map
 addConf          :: ConfMap -> FilePath -> IO ConfMap
 addConf cmp conf = do cnts <- BS.unpack `fmap` BS.readFile conf
-                      case (reads cnts) of
+                      case reads cnts of
                         []       -> return cmp
                         -- ebuilds that have CABAL_CORE_LIB_GHC_PV set
                         -- for this version of GHC will have a .conf
@@ -150,9 +150,7 @@ oldGhcPkgs v =
        -- It would be nice to do this, but we can't assume
        -- some crazy user hasn't deleted one of these dirs
        -- libFronts' <- filterM doesDirectoryExist libFronts
-       pkgs <- liftM notGHC
-               $ checkLibDirs v thisGhc' libFronts
-       return pkgs
+       liftM notGHC $ checkLibDirs v thisGhc' libFronts
 
 -- Find packages installed by other versions of GHC in this possible
 -- library directory.
@@ -163,7 +161,7 @@ checkLibDirs v thisGhc libDirs =
   where
     wanted dir = isValid dir && (not . isInvalid) dir
 
-    isValid dir = any (\ldir -> isGhcLibDir ldir dir) libDirs
+    isValid dir = any (`isGhcLibDir` dir) libDirs
 
     -- Invalid if it's this GHC
     isInvalid fp = fp == thisGhc || BS.isPrefixOf (thisGhc `BS.snoc` pathSeparator) fp
@@ -222,6 +220,5 @@ getBroken = liftM (mapMaybe simpleParse . words)
 allInstalledPackages :: IO [Package]
 allInstalledPackages = do libDir <- ghcLibDir
                           let libDir' = BS.pack libDir
-                          pkgs <- liftM notGHC
-                                  $ pkgsHaveContent $ hasDirMatching (==libDir')
-                          return pkgs
+                          liftM notGHC $ pkgsHaveContent
+                                       $ hasDirMatching (==libDir')

Distribution/Gentoo/Packages.hs

@@ -59,7 +59,7 @@ ghcPkg = Package "dev-lang" "ghc" Nothing
 
 -- Return all packages that are not a version of GHC.
 notGHC :: [Package] -> [Package]
-notGHC = filter (\p -> isNot ghcPkg p)
+notGHC = filter (isNot ghcPkg)
   where
     isNot p1 = not . samePackageAs p1
 
@@ -182,7 +182,7 @@ haveFiles :: [FilePath] -> IO [Package]
 haveFiles fps = pkgsHaveContent p
   where
     fps' = S.fromList $ map BS.pack fps
-    p = hasObjMatching (\fp -> S.member fp fps')
+    p = hasObjMatching (`S.member` fps')
 
 -- Find which packages have Content information that matches the
 -- provided predicate; to be used with the searching predicates

Distribution/Gentoo/PkgManager.hs

@@ -43,7 +43,7 @@ data PkgManager = Portage
 --   defined, if it is unknown then it won't be used.
 defaultPM :: IO PkgManager
 defaultPM = do eDPM <- lookup "PACKAGE_MANAGER" `fmap` getEnvironment
-               let dPM = maybe defaultPMName id eDPM
+               let dPM = fromMaybe defaultPMName eDPM
                    mPM = dPM `M.lookup` pmNameMap
                return $ fromMaybe knownDef mPM
   where
@@ -77,7 +77,7 @@ nameOfPM pm                 = pmNameMap' M.! pm
 -- | Choose the appropriate PM from the textual representation; throws
 --   an error if that PM isn't known.
 choosePM    :: String -> PkgManager
-choosePM pm = maybe (InvalidPM pm) id $ pm' `M.lookup` pmNameMap
+choosePM pm = fromMaybe (InvalidPM pm) $ pm' `M.lookup` pmNameMap
     where
       pm' = map toLower pm
 

Main.hs

@@ -23,7 +23,7 @@ import qualified Data.Set as Set
 import qualified Paths_haskell_updater as Paths(version)
 import System.Console.GetOpt
 import System.Environment(getArgs, getProgName)
-import System.Exit(ExitCode(..), exitWith)
+import System.Exit(ExitCode(..), exitSuccess, exitWith)
 import System.IO(hPutStrLn, stderr)
 import Control.Monad(liftM, unless)
 import System.Process(rawSystem)
@@ -62,7 +62,7 @@ combineAllActions = emptyElse defaultAction (foldl1' combineActions)
 -- Note that it's safe (at the moment at least) to assume that when
 -- the lower of one is a Build that they're both build.
 combineActions       :: Action -> Action -> Action
-combineActions a1 a2 = case (a1 `min` a2) of
+combineActions a1 a2 = case a1 `min` a2 of
                          Help    -> Help
                          Version -> Version
                          Build{} -> Build $ targets a1 `Set.union` targets a2
@@ -143,7 +143,7 @@ data WithCmd = RunOnly
 runCmd :: WithCmd -> String -> [String] -> IO a
 runCmd mode cmd args = case mode of
         RunOnly     ->                      runCommand cmd args
-        PrintOnly   -> putStrLn cmd_line >> exitWith (ExitSuccess)
+        PrintOnly   -> putStrLn cmd_line >> exitSuccess
         PrintAndRun -> putStrLn cmd_line >> runCommand cmd args
     where cmd_line = unwords (cmd:args)
 
@@ -250,7 +250,7 @@ options =
       "Print this help message."
     ]
     where
-      pmList = unlines . map ((++) "  * ") $ definedPMs
+      pmList = unlines . map (" * " ++) $ definedPMs
       defPM = "The last valid value of PM specified is chosen.\n\
               \The default package manager is: " ++ defaultPMName ++ ",\n\
               \which can be overriden with the \"PACKAGE_MANAGER\"\n\
@@ -297,7 +297,7 @@ systemInfo v rm = do ver    <- ghcVersion
 
 success :: Verbosity -> String -> IO a
 success v msg = do say v msg
-                   exitWith ExitSuccess
+                   exitSuccess
 
 die     :: String -> IO a
 die msg = do putErrLn ("ERROR: " ++ msg)