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POUsing "runghc" in Snap and not throw a webhandler exception. Using tryIO still gives an error
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2013-01-06T20:29:47.463
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2014-05-21T08:30:20.533
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2013-02-05T00:36:33.400
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I am trying to use runGHC inside of snap to filter out only code that can be compiled. However, I am using tryIO but still my webhandler throws an exception when there is a compile error instead of just returning an empty String. <pre><code>import Exception (tryIO) ... runOnFileName :: String -> IO (String) runOnFileName inp = do res <- sanitizeSource inp case res of Just (code, _, _, _) -> return $ ppr code Nothing -> return "" sanitizeSourceString :: String -> String -> IO (String) sanitizeSourceString fn contents = do tmpdir <- getTemporaryDirectory let tmp = tmpdir </> fn ++ ".hs" exists <- doesFileExist tmp unless exists $ writeFile tmp $ contents runOnFileName tmp sanitizeSource :: String -> IO (Maybe RenamedSource) sanitizeSource inp = do runGhc (Just libdir) $ do dflags <- getSessionDynFlags let dflags' = foldl xopt_set dflags [Opt_Cpp, Opt_ImplicitPrelude, Opt_MagicHash] setSessionDynFlags dflags target <- guessTarget inp Nothing setTargets [target] load LoadAllTargets modSum <- getModSummary $ mkModuleName "Main" p <- parseModule modSum t <- typecheckModule p d <- desugarModule t return $ renamedSource d ... in my handler... eitherSan <- liftIO $ tryIO $ sanitizeSourceString (T.unpack uuid) (fromMaybe "" content) let sanitized = case eitherSan of Left _ -> "" Right r -> r </code></pre> However, if I pass "content" that does not compile, my handler fails with a <pre><code> A web handler threw an exception. Details Parse error: naked expression at top level </code></pre> or whatever the compiler error is. I thought <code>tryIO</code> was supposed to catch the exception.
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<haskell><snap-framework>
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Using "runghc" in Snap and not throw a webhandler exception. Using tryIO still gives an error
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