Reduced clutter in monadic code

+ Eliminated vairous ad-hoc coersion functions between specific monads 
  (IO, Err, IOE, Check) in favor of more general lifting functions
  (liftIO, liftErr).
+ Generalized many basic monadic operations from specific monads to
  arbitrary monads in the appropriate class (MonadIO and/or ErrorMonad),
  thereby completely eliminating the need for lifting functions in lots
  of places.

This can be considered a small step forward towards a cleaner
compiler API and more malleable compiler code in general.

1 files changed, 6 insertions, 6 deletions

diff --git a/src/compiler/GFC.hs b/src/compiler/GFC.hs
index f75a39ab1..dd9f1771b 100644
--- a/src/compiler/GFC.hs
+++ b/src/compiler/GFC.hs
@@ -55,9 +55,9 @@ compileSourceFiles opts fs =
 
 compileCFFiles :: Options -> [FilePath] -> IOE ()
 compileCFFiles opts fs = 
-    do s  <- ioeIO $ fmap unlines $ mapM readFile fs 
+    do s  <- liftIO $ fmap unlines $ mapM readFile fs
        let cnc = justModuleName (last fs)
-       gf <- ioeErr $ getCF cnc s
+       gf <- getCF cnc s
        gr <- compileSourceGrammar opts gf
        if flag optStopAfterPhase opts == Compile 
          then return ()
@@ -76,7 +76,7 @@ unionPGFFiles opts fs =
          then putStrLnE $ "Refusing to overwrite " ++ pgfFile
          else writePGF opts pgf
        writeOutputs opts pgf
-  where readPGFVerbose f = putPointE Normal opts ("Reading " ++ f ++ "...") $ ioeIO $ readPGF f
+  where readPGFVerbose f = putPointE Normal opts ("Reading " ++ f ++ "...") $ liftIO $ readPGF f
 
 writeOutputs :: Options -> PGF -> IOE ()
 writeOutputs opts pgf = do
@@ -93,7 +93,7 @@ writeByteCode opts pgf
                  path = case flag optOutputDir opts of
                           Nothing  -> file
                           Just dir -> dir </> file
-             in putPointE Normal opts ("Writing " ++ path ++ "...") $ ioeIO $
+             in putPointE Normal opts ("Writing " ++ path ++ "...") $ liftIO $
                    bracket
                       (openFile path WriteMode)
                       (hClose)
@@ -109,14 +109,14 @@ writeByteCode opts pgf
 writePGF :: Options -> PGF -> IOE ()
 writePGF opts pgf = do
   let outfile = grammarName opts pgf <.> "pgf"
-  putPointE Normal opts ("Writing " ++ outfile ++ "...") $ ioeIO $ encodeFile outfile pgf
+  putPointE Normal opts ("Writing " ++ outfile ++ "...") $ liftIO $ encodeFile outfile pgf
 
 grammarName :: Options -> PGF -> String
 grammarName opts pgf = fromMaybe (showCId (absname pgf)) (flag optName opts)
 
 writeOutput :: Options -> FilePath-> String -> IOE ()
 writeOutput opts file str =
-    putPointE Normal opts ("Writing " ++ path ++ "...") $ ioeIO $
+    putPointE Normal opts ("Writing " ++ path ++ "...") $ liftIO $
       writeUTF8File path str
   where
     path = maybe id (</>) (flag optOutputDir opts) file