Hello, So I've been trying to print some information in a file. I have two versions of the same function: one of them doesn't work and I don't understand why. Here are the functions: # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # -- This one works as intended when called from ghci renderTrackInfosToFile :: FilePath -> String -> IO [TrackInfos] -> IO () renderTrackInfosToFile filename sep ls = do nls <- ls writeFile filename (intercalate "\n" $ map (renderTrackInfo sep) nls) return () -- This one does nothing when called from ghci renderTrackInfosToFile2 :: FilePath -> String -> [TrackInfos] -> IO () renderTrackInfosToFile2 filename sep ls = writeFile filename (intercalate "\n" $ map (renderTrackInfo sep) ls) renderTrackInfo :: String -> TrackInfos -> String # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # Both functions load in ghci, and the following commands are issued:
-- c :: IO [TrackInfos] liftM (renderTrackInfosToFile2 "blabla.txt" "|") c -- this command seems to do absolutely nothing renderTrackInfosToFile "blabla.txt" "|" c -- this one works as intended
# # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # And this is not the first time I have this sort of problem using liftM. I now that I'm missing something important here, can anyone explain me my mistake? Much thanks, Guillaume Basse