Safe Haskell | None |
---|---|
Language | Haskell2010 |
Scanner
Description
Fast not-backtracking incremental scanner for bytestrings
Unlike attoparsec or most of other parser combinator libraries, scanner doesn't support backtracking. But you probably don't need it anyway, at least if you need fast parser.
Scanner processes input incrementally. When more input is needed, scanner
returns More
continuation. All the already processed input is discarded.
- data Scanner a
- data Result r
- = Done ByteString r
- | Fail ByteString String
- | More (ByteString -> Result r)
- scan :: Scanner r -> ByteString -> Result r
- scanOnly :: Scanner a -> ByteString -> Either String a
- scanLazy :: Scanner a -> ByteString -> Either String a
- scanWith :: Monad m => m ByteString -> Scanner a -> ByteString -> m (Result a)
- anyWord8 :: Scanner Word8
- anyChar8 :: Scanner Char
- word8 :: Word8 -> Scanner ()
- char8 :: Char -> Scanner ()
- take :: Int -> Scanner ByteString
- takeWhile :: (Word8 -> Bool) -> Scanner ByteString
- takeWhileChar8 :: (Char -> Bool) -> Scanner ByteString
- string :: ByteString -> Scanner ()
- skipWhile :: (Word8 -> Bool) -> Scanner ()
- skipSpace :: Scanner ()
- lookAhead :: Scanner (Maybe Word8)
- lookAheadChar8 :: Scanner (Maybe Char)
Documentation
CPS scanner without backtracking
Scanner result
Constructors
Done ByteString r | Successful result with the rest of input |
Fail ByteString String | Scanner failed with rest of input and error message |
More (ByteString -> Result r) | Need more input |
scan :: Scanner r -> ByteString -> Result r #
Run scanner with the input
scanOnly :: Scanner a -> ByteString -> Either String a #
Scan the complete input, without resupplying
scanLazy :: Scanner a -> ByteString -> Either String a #
Scan lazy bytestring by resupplying scanner with chunks
scanWith :: Monad m => m ByteString -> Scanner a -> ByteString -> m (Result a) #
Scan with the provided resupply action
take :: Int -> Scanner ByteString #
Take the specified number of bytes
takeWhileChar8 :: (Char -> Bool) -> Scanner ByteString #
Take input while the predicate is True
string :: ByteString -> Scanner () #
Consume the specified string
Warning: it is not optimized yet, so for for small string it is better
to consume it byte-by-byte using word8
lookAheadChar8 :: Scanner (Maybe Char) #
Return the next byte, if any, without consuming it