Using io-choice.

AA.hs

@@ -1,42 +0,0 @@
-{-# LANGUAGE ScopedTypeVariables, DeriveDataTypeable #-}
-{-# OPTIONS_GHC -fno-warn-orphans #-}
-
-module AA where
-
-import Control.Applicative
-import Control.Exception
-import Control.Monad
-import CoreMonad
-import Data.Typeable
-import Exception
-import GHC
-
-----------------------------------------------------------------
-
-instance Applicative Ghc where
-    pure  = return
-    (<*>) = ap
-
-instance Alternative Ghc where
-  empty = goNext
-  x <|> y = x `gcatch` (\(_ :: SomeException) -> y)
-
-----------------------------------------------------------------
-
-{-| Go to the next 'Ghc' monad by throwing 'AltGhcgoNext'.
--}
-goNext :: Ghc a
-goNext = liftIO $ throwIO AltGhcgoNext
-
-{-| Run any one 'Ghc' monad.
--}
-runAnyOne :: [Ghc a] -> Ghc a
-runAnyOne = foldr (<|>) goNext
-
-----------------------------------------------------------------
-
-{-| Exception to control 'Alternative' 'Ghc'.
--}
-data AltGhcgoNext = AltGhcgoNext deriving (Show, Typeable)
-
-instance Exception AltGhcgoNext

Cabal.hs

@@ -14,6 +14,7 @@ import Distribution.Verbosity (silent)
 import ErrMsg
 import GHC
 import GHCApi
+import GHCChoice
 import qualified Gap
 import Language.Haskell.Extension
 import System.Directory
@@ -26,7 +27,7 @@ importDirs :: [String]
 importDirs = [".","..","../..","../../..","../../../..","../../../../.."]
 
 initializeGHC :: Options -> FilePath -> [String] -> Bool -> Ghc (FilePath,LogReader)
-initializeGHC opt fileName ghcOptions logging = withCabal <|> withoutCabal
+initializeGHC opt fileName ghcOptions logging = withCabal ||> withoutCabal
   where
     withoutCabal = do
         logReader <- initSession opt ghcOptions importDirs logging

CabalDev.hs

@@ -5,17 +5,17 @@ module CabalDev (modifyOptions) where
   options ghc-mod uses to check the source.  Otherwise just pass it on.
 -}
 
-import Control.Applicative ((<$>),(<|>))
+import Control.Applicative ((<$>))
 import Control.Exception (throwIO)
+import Control.Exception.IOChoice
 import Data.List (find)
 import System.Directory
 import System.FilePath (splitPath,joinPath,(</>))
 import Text.Regex.Posix ((=~))
 import Types
-import Data.Alternative.IO ()
 
 modifyOptions :: Options -> IO Options
-modifyOptions opts = found <|> notFound
+modifyOptions opts = found ||> notFound
   where
     found = addPath opts <$> findCabalDev
     notFound = return opts

GHCChoice.hs

@@ -0,0 +1,25 @@
+{-# LANGUAGE ScopedTypeVariables #-}
+
+module GHCChoice where
+
+import Control.Exception
+import CoreMonad
+import Exception
+import GHC
+
+----------------------------------------------------------------
+
+(||>) :: Ghc a -> Ghc a -> Ghc a
+x ||> y = x `gcatch` (\(_ :: IOException) -> y)
+
+----------------------------------------------------------------
+
+{-| Go to the next 'Ghc' monad by throwing 'AltGhcgoNext'.
+-}
+goNext :: Ghc a
+goNext = liftIO . throwIO $ userError "goNext"
+
+{-| Run any one 'Ghc' monad.
+-}
+runAnyOne :: [Ghc a] -> Ghc a
+runAnyOne = foldr (||>) goNext

Gap.hs

@@ -16,12 +16,12 @@ module Gap (
 #endif
   ) where
 
-import AA ()
 import Control.Applicative hiding (empty)
 import Control.Monad
 import DynFlags
 import FastString
 import GHC
+import GHCChoice
 import Language.Haskell.Extension
 import Outputable
 import StringBuffer
@@ -117,7 +117,7 @@ setCtx ms = do
     return (not . null $ top)
 #endif
   where
-    isTop mos = lookupMod <|> returnFalse
+    isTop mos = lookupMod ||> returnFalse
       where
         lookupMod = lookupModule (ms_mod_name mos) Nothing >> return True
         returnFalse = return False

Info.hs

@@ -2,7 +2,6 @@
 
 module Info (infoExpr, typeExpr) where
 
-import AA
 import Cabal
 import Control.Applicative
 import CoreUtils
@@ -15,6 +14,7 @@ import Desugar
 import GHC
 import GHC.SYB.Utils
 import GHCApi
+import GHCChoice
 import qualified Gap
 import HscTypes
 import NameSet
@@ -127,7 +127,7 @@ pprInfo pefas (thing, fixity, insts)
 
 inModuleContext :: Options -> FilePath -> ModuleString -> Ghc String -> String -> IO String
 inModuleContext opt fileName modstr action errmsg =
-    withGHC (valid <|> invalid <|> return errmsg)
+    withGHC (valid ||> invalid ||> return errmsg)
   where
     valid = do
         (file,_) <- initializeGHC opt fileName ["-w"] False

ghc-mod.cabal

@@ -23,14 +23,14 @@ Data-Files:             Makefile ghc.el ghc-func.el ghc-doc.el ghc-comp.el
                         ghc-flymake.el ghc-command.el ghc-info.el ghc-ins-mod.el
 Executable ghc-mod
   Main-Is:              GHCMod.hs
-  Other-Modules:        AA
-                        Browse
+  Other-Modules:        Browse
                         Cabal
                         CabalDev
                         Check
                         ErrMsg
                         Flag
                         GHCApi
+                        GHCChoice
                         Gap
                         Info
                         Lang
@@ -44,13 +44,13 @@ Executable ghc-mod
     GHC-Options:        -Wall
   Build-Depends:        base >= 4.0 && < 5
                       , Cabal
-                      , alternative-io
                       , directory
                       , filepath
                       , ghc
                       , ghc-paths
                       , ghc-syb-utils
                       , hlint >= 1.7.1
+                      , io-choice
                       , old-time
                       , process
                       , regex-posix