http-conduit issues

gistfile1.hs

-- | Fetch the contents of a uri, which must be an ascii string.
-- Redirects, authentication, https: and file: uris are supported.
readUri :: Manager -> String -> Opts -> IO String
readUri manager s opts =
    case parseURI' s of
      Just URI{uriScheme="file:",uriPath=f} -> readFeedFile f
      Just _ -> do
        r <- parseUrl s
        let cachecontrol = cache_control opts
            r' | null cachecontrol = r
               | otherwise = r{requestHeaders=(hCacheControl, B8.pack cachecontrol):requestHeaders r}
        rsp <- httpLbs r' manager
        return $ LB8.unpack $ responseBody rsp --  $$+- return ()  ? https://github.com/snoyberg/http-conduit/issues/97#issuecomment-12876868
      Nothing -> opterror $ "could not parse URI: " ++ s

gistfile2.txt

[3 of 5] Compiling Feed             ( Feed.hs, Feed.o )

Feed.hs:183:16:
    No instance for (Control.Monad.Trans.Resource.MonadResource IO)
      arising from a use of `httpLbs'
    Possible fix:
      add an instance declaration for
      (Control.Monad.Trans.Resource.MonadResource IO)
    In a stmt of a 'do' block: rsp <- httpLbs r' manager
    In the expression:
      do { r <- parseUrl s;
           let cachecontrol = cache_control opts
               r'
                 | null cachecontrol = r
                 | otherwise = ...;
           rsp <- httpLbs r' manager;
           return $ LB8.unpack $ responseBody rsp }
    In a case alternative:
        Just _
          -> do { r <- parseUrl s;
                  let cachecontrol = ...
                      ....;
                  rsp <- httpLbs r' manager;
                  .... }