module Data.Encoding.ASCII
(ASCII(..)) where
import Control.Exception (throwDyn)
import Data.ByteString (pack)
import qualified Data.ByteString.Lazy as Lazy (pack)
import Data.ByteString.Char8 (unpack)
import Data.Char (ord)
import qualified Data.ByteString.Lazy as Lazy
import Data.Encoding.Base
import Data.Word
import Data.Typeable
data ASCII = ASCII deriving (Show,Eq,Typeable)
charToASCII :: Char -> Word8
charToASCII ch = if ch < '\128'
then fromIntegral $ ord ch
else throwDyn (HasNoRepresentation ch)
instance Encoding ASCII where
encode _ str = pack (map charToASCII str)
encodeLazy _ str = Lazy.pack (map charToASCII str)
encodable _ ch = ch < '\128'
decode _ = unpack
decodable _ = const True