-l for check.

Language/Haskell/GhcMod/Check.hs

@@ -18,7 +18,7 @@ checkSyntax :: Options
             -> [FilePath]  -- ^ The target files.
             -> IO String
 checkSyntax _   _      []    = error "ghc-mod: checkSyntax: No files given"
-checkSyntax opt cradle files = unlines <$> withGHC sessionName (check opt cradle files)
+checkSyntax opt cradle files = convert opt <$> withGHC sessionName (check opt cradle files)
   where
     sessionName = case files of
       [file] -> file

Language/Haskell/GhcMod/Internal.hs

@@ -31,6 +31,8 @@ module Language.Haskell.GhcMod.Internal (
   , runAnyOne
   -- * 'GhcMonad' Choice
   , (|||>)
+  -- * Misc
+  , convert
   ) where
 
 import Language.Haskell.GhcMod.Browse

Language/Haskell/GhcMod/Types.hs

@@ -75,7 +75,11 @@ tupToString ((a,b,c,d),s) = show a ++ " "
                          ++ quote s
 
 quote :: String -> String
-quote x = "\"" ++ x ++ "\""
+quote x = "\"" ++ escape x ++ "\""
+  where
+    escape [] = []
+    escape ('"':ys) = '\\':'\"':escape ys
+    escape (y:ys)   = y:escape ys
 
 addNewLine :: String -> String
 addNewLine = (++ "\n")