{- Copyright 2008 Debris <debris>

This file is part of rcc.
rcc is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

rcc is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with rcc; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

$Id: rcc.hs,v 0.1 2008/07/04 08:16 debris $ -}

-- Import main libraries.
-- Environment, and the parsec monad.
module Main where
import System.Environment
import Text.ParserCombinators.Parsec hiding (spaces)

-- main application entry point.
-- parse input expression on args.
main :: IO ()
main = do args <- getArgs
          putStrLn (rccParseExpression (args !! 0))

-- Symbols definition.
-- oneOf should be working by defining symbols to be any
-- of the instances we mention in the string attached. 
rccSymbols :: Parser Char
rccSymbols = oneOf "!$%&|*+-/:<=>?@^_~#"

-- Spaces definition.
-- spaces should not be taken in consideration, so we use
-- the skipMany1 function to skip them out of the parser.
rccSpaces :: Parser ()
rccSpaces = skipMany1 space

-- Type definitions.
-- types are currently somekind limited but they should 
-- be enough to perform some computation.
data Type = AtomicType   String
          | BooleanType  Bool
          | DoubleType   Double
          | IntegerType  Integer
          | ListType     [Type]
          | PairType     [Type] Type
          | StringType   String

-- Parse input expression.
-- checks for errors using symbols found.
rccParseExpression :: String -> String
rccParseExpression input = case parse (rccSpaces >> rccSymbols) "" input of
    Left err -> "Syntax error: Symbol expected at" ++ show err
    Right val -> "Found value"