diff options
Diffstat (limited to 'libraries/ghc-boot/GHC/Utils/Encoding.hs')
| -rw-r--r-- | libraries/ghc-boot/GHC/Utils/Encoding.hs | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/libraries/ghc-boot/GHC/Utils/Encoding.hs b/libraries/ghc-boot/GHC/Utils/Encoding.hs index ba07784b0d..5eb3779b3b 100644 --- a/libraries/ghc-boot/GHC/Utils/Encoding.hs +++ b/libraries/ghc-boot/GHC/Utils/Encoding.hs @@ -22,6 +22,7 @@ module GHC.Utils.Encoding ( utf8CharStart, utf8DecodeChar, utf8DecodeByteString, + utf8UnconsByteString, utf8DecodeShortByteString, utf8CompareShortByteString, utf8DecodeStringLazy, @@ -169,6 +170,14 @@ utf8DecodeByteString :: ByteString -> [Char] utf8DecodeByteString (BS.PS fptr offset len) = utf8DecodeStringLazy fptr offset len +utf8UnconsByteString :: ByteString -> Maybe (Char, ByteString) +utf8UnconsByteString (BS.PS _ _ 0) = Nothing +utf8UnconsByteString (BS.PS fptr offset len) + = unsafeDupablePerformIO $ + withForeignPtr fptr $ \ptr -> do + let (c,n) = utf8DecodeChar (ptr `plusPtr` offset) + return $ Just (c, BS.PS fptr (offset + n) (len - n)) + utf8DecodeStringLazy :: ForeignPtr Word8 -> Int -> Int -> [Char] utf8DecodeStringLazy fp offset (I# len#) = unsafeDupablePerformIO $ do |