Question about Haskell AST

Ian Lynagh igloo at earth.li
Tue Feb 22 16:09:18 CET 2011


Hi Jane,

On Mon, Feb 21, 2011 at 11:46:16PM -0800, Jane Ren wrote:
> 
> Did you mean I have to include the dflags like below to get the parsetree of a base library file like libraries/base/GHC/List.lhs
>  
> I am stilling getting the same error 
> AstWalker: panic! (the 'impossible' happened)
>   (GHC version 7.0.1 for x86_64-apple-darwin):
> 	lexical error at character 'i'
> 
> my code is 	"...
>         setSessionDynFlags ...
>         target <- guessTarget targetFile Nothing
> 	setTargets [target]
>         load LoadAllTargets"
> 
> Would you have any other suggestions?

This works for me with the 7.0 branch:

main :: IO ()
main =
    defaultErrorHandler defaultDynFlags $ do
      runGhc (Just libdir) $ do
        dflags <- getSessionDynFlags
        let dflags' = foldl xopt_set dflags 
                            [Opt_Cpp, Opt_ImplicitPrelude, Opt_MagicHash]
        setSessionDynFlags dflags'
        target <- guessTarget fp Nothing
        setTargets [target]
        load LoadAllTargets
        liftIO $ putStrLn "Done"

Let me know if you still have problems.


Thanks
Ian




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