arbu

import Data.List

data Formula = Atom String | Unary String Formula | Binary String Formula Formula

instance Show Formula where
    show (Atom name) = name
    show (Unary op remaining) = op ++ " " ++ (show remaining)
    show (Binary op left right) = "(" ++ (show left) ++ " " ++ op ++ " " ++ (show right) ++ ")"

unaries = ["-"]