Thanks, that fixed it. Why was it segfaulting on "Nothing" though?
Secondly, I'd like to get to a GHC session that just has, say, Prelude in scope so I can use dynCompileExpr with "show" etc, but I cannot figure out how to bring it into scope. The closest I got was to get GHC complaining that it was a package module. On Sun, Feb 27, 2011 at 9:24 AM, Anthonin Bonnefoy <anthonin.bonne...@gmail.com> wrote: > Hi, > > The first argument of runGhc takes the directory where GHC's library > are. You can use the ghc-paths module > (http://hackage.haskell.org/package/ghc-paths ) for this. > > Just install ghc-paths with cabal, import Ghc.Paths and call runGhc > with (Just libdir), it should get past the segfault. > > On Sun, Feb 27, 2011 at 10:51 AM, Edward Amsden <eca7...@cs.rit.edu> wrote: >> I'm trying to run the following code. I'm not at all sure it's >> correct, it's based off of a bit of poking around in the ghc api. >> Running it with a command line argument like "show (5 + 2)" gives me a >> segmentation fault. Poking around with gdb and following the steps at >> http://hackage.haskell.org/trac/ghc/wiki/Debugging/CompiledCode yields >> precisely nothing, as even the "disassemble" command complains "No >> function contains program counter for selected frame." >> >> Any ideas? >> >> == code == >> module Main where >> >> import GHC >> import DynFlags >> import Data.Dynamic >> import System >> >> evalString :: Typeable a => String -> IO (Maybe a) >> evalString s = defaultErrorHandler defaultDynFlags $ runGhc Nothing $ do >> dynflags <- getSessionDynFlags >> setSessionDynFlags $ dynflags >> target <- guessTarget "Prelude" Nothing >> setTargets [target] >> load LoadAllTargets >> >> dyn <- dynCompileExpr s >> return $ fromDynamic dyn >> >> main = do >> (s:_) <- getArgs >> e <- evalString s >> putStrLn $ maybe "oops" id e >> >> -- >> Edward Amsden >> Undergraduate >> Computer Science >> Rochester Institute of Technology >> www.edwardamsden.com >> >> _______________________________________________ >> Haskell-Cafe mailing list >> Haskell-Cafe@haskell.org >> http://www.haskell.org/mailman/listinfo/haskell-cafe >> > > _______________________________________________ > Haskell-Cafe mailing list > Haskell-Cafe@haskell.org > http://www.haskell.org/mailman/listinfo/haskell-cafe > -- Edward Amsden Undergraduate Computer Science Rochester Institute of Technology www.edwardamsden.com _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
