18 lines
449 B
Haskell
18 lines
449 B
Haskell
module Main where
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import Control.Monad (forever)
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import System.IO (hFlush, stdout)
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import UntypedLambdaCalculus (eval)
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import UntypedLambdaCalculus.Parser (parseExpr)
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prompt :: String -> IO String
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prompt text = do
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putStr text
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hFlush stdout
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getLine
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main :: IO ()
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main = forever $ parseExpr "stdin" <$> prompt ">> " >>= \case
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Left parseError -> putStrLn $ "Parse error: " ++ show parseError
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Right expr -> do print expr; print $ eval expr
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