gistfile1.txt

I have a function

GIT_EXTERN(int) git_repository_open(git_repository **repository, const char *path);

Return int is a possible error code. Actual value I'm interested in is **repository

Haskell code:


openRepo :: String -> IO (Either GitError Repository)
openRepo path = do
  let repo = nullPtr
  pstr <- newCString path
  res  <- {#call git_repository_open#} repo pstr
  return $ case res of
             0 -> Right $ Repository repo
             n -> Left . toEnum . fromIntegral $ n

newtype Repository = Repository { unRepository :: Ptr () }

This is not going too well:

Assertion failed: (repo_out && path), function git_repository_open, file repository.c, line 347.

What's going wrong here?