James Eversole
b3583c796e
Includes better error handling, additional tests, parsing and lexing fixes to match the desired behavior defined by the new tests, and a very basic REPL implementation.
26 lines
608 B
Haskell
26 lines
608 B
Haskell
module REPL where
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import Eval
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import Lexer
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import Parser
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import Research
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import Control.Monad (void)
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import qualified Data.Map as Map
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import System.IO (hFlush, stdout)
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repl :: Map.Map String T -> IO ()
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repl env = do
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putStr "sapling > "
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hFlush stdout
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input <- getLine
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if input == "_:exit"
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then putStrLn "Goodbye!"
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else do
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let clearEnv = Map.delete "__result" env
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let newEnv = evalSingle clearEnv (parseSingle input)
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case Map.lookup "__result" newEnv of
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Just r -> putStrLn $ "sapling < " ++ show r
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Nothing -> pure ()
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repl newEnv
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