At a guess, because the ghc package defaults to being hidden (it's creating
a new ghc instance at runtime, so the visibility of the ghc package when
compiling your code is not relevant) you need to do the ghc-api equivalent
of "-package ghc". Or for testing just "ghc-pkg expose ghc".
On Fri, Aug 2, 2019 at 3:47 PM Sam Halliday
To answer my own question with a solution and another question:
Sam Halliday writes:
I'm mostly interested in gathering information about symbols and their type signatures. As a first exercise: given a module+import section for a haskell source file, I want to find out which symbols (and their types) are available. Like :browse in ghci, but programmatically.
This is answered by Stephen Diehl's blog post on the ghc api! How lucky I am: http://www.stephendiehl.com/posts/ghc_01.html
He points to getNamesInScope
Unfortunately I'm getting zero Names back when loading a file that imports several modules from ghc. Is there something I'm missing in the following?
module Main where
import Control.Monad import Control.Monad.IO.Class import GHC import GHC.Paths (libdir)
main = runGhc (Just libdir) $ do dflags <- getSessionDynFlags void $ setSessionDynFlags $ dflags { hscTarget = HscInterpreted , ghcLink = LinkInMemory } addTarget $ Target (TargetFile "exe/Main.hs" Nothing) False Nothing res <- load LoadAllTargets liftIO $ putStrLn $ showPpr dflags res names <- getNamesInScope liftIO $ putStrLn $ "seen " <> (show $ length names) <> " Names"
-- Best regards, Sam _______________________________________________ ghc-devs mailing list ghc-devs@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs
-- brandon s allbery kf8nh allbery.b@gmail.com