app/Main.hs

   1 module Main where
   2 import Text.ParserCombinators.Parsec hiding (spaces)
   3 import System.Environment
   4
   5 symbol :: Parser Char
   6 symbol = oneOf "!#$%&|*+-/:<=>?@^_~"
   7
   8 spaces :: Parser ()
   9 spaces = skipMany space
  10
  11 readExpr :: String -> String
  12 readExpr input = case parse (spaces >> symbol) "lisp" input of
  13     Left err -> "No match: " ++ show err
  14     Right val -> "Found value"
  15
  16 main :: IO ()
  17 main = do
  18     args <- getLine
  19     putStrLn (readExpr args)