pureIOtest.hs

main = interact prg

prg :: String -> String -- pure function!

prg s = unlines $ [ "What is your name?"
                  , "Hi, " ++ name ++ "!"
                  , "Where do you live?"
                  , place ++ " is very nice, isn't it?" ]
                  ++ re 2 (lns !! 2)
  where lns        = lines s
        name       = lns !! 0
        place      = lns !! 1
        re c "yes" = [ "I thought so!"
                     , "Goodbye, " ++ name ++ "!" ]
        re c "no"  = [ "Oh, that's unfortunate."
                     , "Anyway, " ++ name ++ ", ja mata ne!" ]
        re c _     = [ "Please answer \"yes\" or \"no\". Let me ask again: isn't it??" ]
                     ++ re (c+1) (lns !! (c+1))