{-# LANGUAGE TemplateHaskell, MultiParamTypeClasses #-}
-- Copyright (c) 2006 Don Stewart - http://www.cse.unsw.edu.au/~dons
-- GPL version 2 or later (see http://www.gnu.org/copyleft/gpl.html)
--
-- | A plugin for the Haskell interpreter for the unlambda language
--
-- http://www.madore.org/~david/programs/unlambda/
module Plugin.Unlambda (theModule) where

import Plugin

$(plugin "Unlambda")

instance Module UnlambdaModule () where
    moduleCmds   _     = ["unlambda"]
    moduleHelp _ _     = "unlambda <expr>. Evaluate an unlambda expression"
    process _ _ to _ s = ios80 to (unlambda s)

binary :: String
binary = "unlambda"

unlambda :: String -> IO String
unlambda src = run binary src scrub
  where scrub = unlines . take 6 . map (' ':) . lines . cleanit

cleanit :: String -> String
cleanit s | terminated `matches'` s = "Terminated\n"
          | otherwise               = s
    where terminated = regex' "waitForProc"