Safe Haskell	None
Language	Haskell98

Data.Binary.Get.Internal

Contents

The Get type
Parsing
Utility
- ByteStrings

Synopsis

The Get type

data Get a Source

Instances

Alternative Get
Monad Get
Functor Get
MonadPlus Get
Applicative Get

runCont :: Get a -> forall r. ByteString -> Success a r -> Decoder r Source

data Decoder a Source

A decoder produced by running a Get monad.

Constructors

Fail !ByteString String	The decoder ran into an error. The decoder either used `fail` or was not provided enough input.
Partial (Maybe ByteString -> Decoder a)	The decoder has consumed the available input and needs more to continue. Provide `Just` if more input is available and `Nothing` otherwise, and you will get a new `Decoder`.
Done !ByteString a	The decoder has successfully finished. Except for the output value you also get the unused input.
BytesRead !Int64 (Int64 -> Decoder a)	The decoder needs to know the current position in the input. Given the number of bytes remaning in the decoder, the outer decoder runner needs to calculate the position and resume the decoding.

Instances

Functor Decoder
Show a => Show (Decoder a)

runGetIncremental :: Get a -> Decoder a Source

Run a Get monad. See Decoder for what to do next, like providing input, handling decoding errors and to get the output value.

readN :: Int -> (ByteString -> a) -> Get a Source

Return at least n bytes, maybe more. If not enough data is available the computation will escape with Partial.

readNWith :: Int -> (Ptr a -> IO a) -> Get a Source

Parsing

skip :: Int -> Get () Source

Skip ahead n bytes. Fails if fewer than n bytes are available.

bytesRead :: Get Int64 Source

Get the total number of bytes read to this point.

isolate Source

Arguments

:: Int	The number of bytes that must be consumed
-> Get a	The decoder to isolate
-> Get a

Isolate a decoder to operate with a fixed number of bytes, and fail if fewer bytes were consumed, or more bytes were attempted to be consumed. If the given decoder fails, isolate will also fail. Offset from bytesRead will be relative to the start of isolate, not the absolute of the input.

get :: Get ByteString Source

Get the current chunk.

put :: ByteString -> Get () Source

Replace the current chunk.

demandInput :: Get () Source

Demand more input. If none available, fail.

ensureN :: Int -> Get () Source

Ensure that there are at least n bytes available. If not, the computation will escape with Partial.

Utility

remaining :: Get Int64 Source

Deprecated: This will force all remaining input, don't use it.

DEPRECATED. Get the number of bytes of remaining input. Note that this is an expensive function to use as in order to calculate how much input remains, all input has to be read and kept in-memory. The decoder keeps the input as a strict bytestring, so you are likely better off by calculating the remaining input in another way.

getBytes :: Int -> Get ByteString Source

Deprecated: Use getByteString instead of getBytes.

DEPRECATED. Same as getByteString.

isEmpty :: Get Bool Source

Test whether all input has been consumed, i.e. there are no remaining undecoded bytes.

lookAhead :: Get a -> Get a Source

Run the given decoder, but without consuming its input. If the given decoder fails, then so will this function.

lookAheadM :: Get (Maybe a) -> Get (Maybe a) Source

Run the given decoder, and only consume its input if it returns Just. If Nothing is returned, the input will be unconsumed. If the given decoder fails, then so will this function.

lookAheadE :: Get (Either a b) -> Get (Either a b) Source

Run the given decoder, and only consume its input if it returns Right. If Left is returned, the input will be unconsumed. If the given decoder fails, then so will this function.

label :: String -> Get a -> Get a Source

ByteStrings

getByteString :: Int -> Get ByteString Source

An efficient get method for strict ByteStrings. Fails if fewer than n bytes are left in the input. If n <= 0 then the empty string is returned.