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-rw-r--r--src/Haddock/Utf8.hs74
1 files changed, 0 insertions, 74 deletions
diff --git a/src/Haddock/Utf8.hs b/src/Haddock/Utf8.hs
deleted file mode 100644
index 1fb0e818..00000000
--- a/src/Haddock/Utf8.hs
+++ /dev/null
@@ -1,74 +0,0 @@
-module Haddock.Utf8 (encodeUtf8, decodeUtf8) where
-import Data.Bits ((.|.), (.&.), shiftL, shiftR)
-import qualified Data.ByteString as BS
-import Data.Char (chr, ord)
-import Data.Word (Word8)
-
--- | Helper that encodes and packs a 'String' into a 'BS.ByteString'
-encodeUtf8 :: String -> BS.ByteString
-encodeUtf8 = BS.pack . encode
-
--- | Helper that unpacks and decodes a 'BS.ByteString' into a 'String'
-decodeUtf8 :: BS.ByteString -> String
-decodeUtf8 = decode . BS.unpack
-
--- Copy/pasted functions from Codec.Binary.UTF8.String for encoding/decoding
--- | Character to use when 'encode' or 'decode' fail for a byte.
-replacementCharacter :: Char
-replacementCharacter = '\xfffd'
-
--- | Encode a Haskell String to a list of Word8 values, in UTF8 format.
-encode :: String -> [Word8]
-encode = concatMap (map fromIntegral . go . ord)
- where
- go oc
- | oc <= 0x7f = [oc]
-
- | oc <= 0x7ff = [ 0xc0 + (oc `shiftR` 6)
- , 0x80 + oc .&. 0x3f
- ]
-
- | oc <= 0xffff = [ 0xe0 + (oc `shiftR` 12)
- , 0x80 + ((oc `shiftR` 6) .&. 0x3f)
- , 0x80 + oc .&. 0x3f
- ]
- | otherwise = [ 0xf0 + (oc `shiftR` 18)
- , 0x80 + ((oc `shiftR` 12) .&. 0x3f)
- , 0x80 + ((oc `shiftR` 6) .&. 0x3f)
- , 0x80 + oc .&. 0x3f
- ]
-
--- | Decode a UTF8 string packed into a list of Word8 values, directly to String
-decode :: [Word8] -> String
-decode [ ] = ""
-decode (c:cs)
- | c < 0x80 = chr (fromEnum c) : decode cs
- | c < 0xc0 = replacementCharacter : decode cs
- | c < 0xe0 = multi1
- | c < 0xf0 = multi_byte 2 0xf 0x800
- | c < 0xf8 = multi_byte 3 0x7 0x10000
- | c < 0xfc = multi_byte 4 0x3 0x200000
- | c < 0xfe = multi_byte 5 0x1 0x4000000
- | otherwise = replacementCharacter : decode cs
- where
- multi1 = case cs of
- c1 : ds | c1 .&. 0xc0 == 0x80 ->
- let d = ((fromEnum c .&. 0x1f) `shiftL` 6) .|. fromEnum (c1 .&. 0x3f)
- in if d >= 0x000080 then toEnum d : decode ds
- else replacementCharacter : decode ds
- _ -> replacementCharacter : decode cs
-
- multi_byte :: Int -> Word8 -> Int -> String
- multi_byte i mask overlong = aux i cs (fromEnum (c .&. mask))
- where
- aux 0 rs acc
- | overlong <= acc && acc <= 0x10ffff &&
- (acc < 0xd800 || 0xdfff < acc) &&
- (acc < 0xfffe || 0xffff < acc) = chr acc : decode rs
- | otherwise = replacementCharacter : decode rs
-
- aux n (r:rs) acc
- | r .&. 0xc0 == 0x80 = aux (n-1) rs
- $ shiftL acc 6 .|. fromEnum (r .&. 0x3f)
-
- aux _ rs _ = replacementCharacter : decode rs