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import System.IO
import Statement
import Parser.Statement
import Parser.Core
import Statement
import Assignment
import Expr
import Evaluation
main = promptLoop []
promptLoop :: Context -> IO ()
promptLoop context = do
line <- prompt
if line /= "exit"
then loop line context >>= promptLoop
else return ()
loop :: String -> Context -> IO Context
loop line context = do s <- parseIO line
context <- printStatement s context
putStrLn $ show context
return context
prompt :: IO String
prompt = do putStr "> "
hFlush stdout
getLine
parseIO :: String -> IO Statement
parseIO input = case parseStrict statementP input of
Nothing -> fail "Couldn't parse input"
Just s -> return s
printStatement :: Statement -> Context -> IO Context
printStatement (SAssignment a) context = do putStrLn $ show a
return $ update context a
printStatement (SExpr e) context = do putStrLn evalStr
return context
where evalStr = case eval context e of Nothing -> "Couldn't evaluate expression"
Just a -> show a
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