encoding/Data/Encoding/KOI8R.hs
Henning Guenther 5b02009636 Removed dependence on Data.ByteString.Internal
darcs-hash:20071105215225-a4fee-c0b55a368ffc296c7c784156f8340cb4586f1444
2007-11-05 13:52:25 -08:00

60 lines
2.2 KiB
Haskell

module Data.Encoding.KOI8R
(KOI8R(..)) where
import Control.Exception (throwDyn)
import Data.Array.Unboxed
import Data.Char (ord,chr)
import qualified Data.ByteString.Lazy as Lazy
import Data.Map hiding (map,(!))
import Data.Word
import Prelude hiding (lookup)
import Data.Encoding.Base
data KOI8R = KOI8R deriving Show
koi8rArr :: UArray Word8 Char
koi8rArr = listArray (128,255) koi8rList
koi8rMap :: Map Char Word8
koi8rMap = fromList (zip koi8rList [0..])
koi8rList :: [Char]
koi8rList =
['\x2500','\x2502','\x250c','\x2510','\x2514','\x2518','\x251c','\x2524'
,'\x252c','\x2534','\x253c','\x2580','\x2584','\x2588','\x258c','\x2590'
,'\x2591','\x2592','\x2593','\x2320','\x25a0','\x2219','\x221a','\x2248'
,'\x2264','\x2265','\x00a0','\x2321','\x00b0','\x00b2','\x00b7','\x00f7'
,'\x2550','\x2551','\x2552','\x0451','\x2553','\x2554','\x2555','\x2556'
,'\x2557','\x2558','\x2559','\x255a','\x255b','\x255c','\x255d','\x255e'
,'\x255f','\x2560','\x2561','\x0401','\x2562','\x2563','\x2564','\x2565'
,'\x2566','\x2567','\x2568','\x2569','\x256a','\x256b','\x256c','\x00a9'
,'\x044e','\x0430','\x0431','\x0446','\x0434','\x0435','\x0444','\x0433'
,'\x0445','\x0438','\x0439','\x043a','\x043b','\x043c','\x043d','\x043e'
,'\x043f','\x044f','\x0440','\x0441','\x0442','\x0443','\x0436','\x0432'
,'\x044c','\x044b','\x0437','\x0448','\x044d','\x0449','\x0447','\x044a'
,'\x042e','\x0410','\x0411','\x0426','\x0414','\x0415','\x0424','\x0413'
,'\x0425','\x0418','\x0419','\x041a','\x041b','\x041c','\x041d','\x041e'
,'\x041f','\x042f','\x0420','\x0421','\x0422','\x0423','\x0416','\x0412'
,'\x042c','\x042b','\x0417','\x0428','\x042d','\x0429','\x0427','\x042a']
koi8rDecode :: Word8 -> Char
koi8rDecode ch
| ch < 128 = chr $ fromIntegral ch
| otherwise = koi8rArr!ch
koi8rEncode :: Char -> Word8
koi8rEncode ch
| ch < '\128' = fromIntegral $ ord ch
| otherwise = case lookup ch koi8rMap of
Just w -> w
Nothing -> throwDyn (HasNoRepresentation ch)
instance Encoding KOI8R where
encode _ = encodeSinglebyte koi8rEncode
encodeLazy _ = encodeSinglebyteLazy koi8rEncode
encodable _ c = (c < '\128') || (member c koi8rMap)
decode _ = decodeSinglebyte koi8rDecode
decodeLazy _ str = concatMap (decodeSinglebyte koi8rDecode) (Lazy.toChunks str)
decodable _ = const True