module StackMachine where

import System.IO

type Transition state input output = (state, input) -> (state, output)

process :: Transition state input output -> state -> [input] -> [output]


runprocess :: Transition state String String -> state -> IO ()
runprocess tr s = do
  hSetBuffering stdout LineBuffering  -- requires: ``import System.IO''
  interact (unlines . process tr s . lines)


countEcho :: Transition Integer String String


trAdd :: Transition Integer String String


polish :: Transition [Integer] String String