melody-0.2: src/Language/Melody.hs

module Language.Melody where
import Language.Melody.Parser
import Language.Melody.Interpret
import Control.Monad
import Control.Monad.Error
import System.Environment
import System.IO

repl :: Melody
repl = forever . flip catchError (liftIO . print) $ do
  liftIO $ putStr ">>> " >> hFlush stdout
  l <- parseMelody `fmap` liftIO getLine
  case l of
    Left err -> liftIO $ print err
    Right m  -> eval m

evalFile :: String -> Melody
evalFile f = do
  res <- liftIO $ parseSrcFile f
  case res of
    Left err        -> liftIO $ print err
    Right toplevels -> mapM_ eval toplevels

main :: IO ()
main = do
  args <- getArgs
  void . runMelody $ mapM_ evalFile args >> repl