Hello, everyone. I am in need of setting up custom exception handlers when using GHC API to compile modules. Right now I have the following piece of code:
* Main.hs: -------------------------------------------------------------------------------------------------- import GHC import GHC.Paths import MonadUtils import Exception import Panic import Unsafe.Coerce import System.IO.Unsafe handleException :: (ExceptionMonad m, MonadIO m) => m a -> m (Either String a) handleException m = ghandle (\(ex :: SomeException) -> return (Left (show ex))) $ handleGhcException (\ge -> return (Left (showGhcException ge ""))) $ flip gfinally (liftIO restoreHandlers) $ m >>= return . Right initGhc :: Ghc () initGhc = do dfs <- getSessionDynFlags setSessionDynFlags $ dfs { hscTarget = HscInterpreted , ghcLink = LinkInMemory } return () test :: IO (Either String Int) test = handleException $ runGhc (Just libdir) $ do initGhc setTargets =<< sequence [ guessTarget "./test/file1.hs" Nothing ] graph <- depanal [] False loaded <- load LoadAllTargets -- when (failed loaded) $ throw LoadingException setContext (map (IIModule . moduleName . ms_mod) graph) let expr = "main" ty <- exprType expr -- throws exception if doesn't typecheck output ty res <- unsafePerformIO . unsafeCoerce <$> compileExpr expr return res -------------------------------------------------------------------------------------------------- * file1.hs: ---------------------------- module Main where main = do return x ---------------------------- The problem is when I run the 'test' function above I receive the following output: h> test test/file1.hs:4:10: Not in scope: `x' Left "Cannot add module Main to context: not a home module" it :: Either String Int So, if I understand this correctly, my exception handler does indeed catch an exception correctly, however, I still receive some output which I want to be captured. Is there a way to do this? -- Sincerely yours, -- Daniil Frumin _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe