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module Parser (
FractranProgram(..),
parseFractran
) where
import Text.Combinators.Parsec
data FractranProgram = FractranProgram { fractions :: [(Int,Int)]
, initialValue :: Int }
deriving (Show)
parseFractran :: String -> Either ParseError FractranProgram
parseFractran = parse fractran "error"
fractran = do
f <- many intPair
v <- initVal
eof
return (FractranProgram f v)
intPair = do
whiteSpace
n <- wholeNumber
slash
d <- wholeNumber
return (n,d)
slash = char '/'
initVal = do
whiteSpace
v <- wholeNumber
whiteSpace
return v
wholeNumber =
whiteSpace = many (oneOf "\t\n\r ")
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