module Main where

import Control.Monad
import Data.Either
import Data.Maybe
import System.Console.Readline

import Simplify
import Parser
import PrettyPrint


repl :: IO ()
repl = do
    mline <- readline "> "
    case mline of
        Nothing -> return ()  -- EOF
        Just "" -> repl
        Just line -> do
            addHistory line
            let eexpr = parseExpression line
            either (putStrLn . ("Error: "++)) handleExpression eexpr
            repl
    where
        handleExpression expr = do
            print expr
            let sim = simplify expr
            print sim

main :: IO ()
main = repl