hc/app/Main.hs

module Main (main) where

import Text.Parsec

import Lib (exprparser, evaluate)

import System.IO

main :: IO ()
main = ioLoop

useResult (Right e) = show . evaluate $ e
useResult (Left  e) = show e

ioLoop :: IO ()
ioLoop = do done <- isEOF
            if done
              then putStrLn "Quit!"
              else do inp <- getLine
                      let expr = parse exprparser "<stdin>" inp
                      putStrLn . useResult $ expr
                      ioLoop