| Safe Haskell | Safe-Inferred |
|---|---|
| Language | Haskell2010 |
Pipes.Binary
Description
pipes utilities for encoding and decoding values as byte streams
The tutorial at the bottom of this module illustrates how to use this library.
In this module, the following type synonym compatible with the lens,
lens-family and lens-family-core libraries is used but not exported:
type Lens' a b = forall f . Functor f => (b -> f b) -> (a -> f a)
Synopsis
- encode :: (Monad m, Binary a) => a -> Proxy x' x () ByteString m ()
- encodePut :: Monad m => Put -> Proxy x' x () ByteString m ()
- decode :: (Monad m, Binary a) => Parser ByteString m (Either DecodingError a)
- decoded :: (Monad m, Binary a) => Lens' (Producer ByteString m r) (Producer a m (Either (DecodingError, Producer ByteString m r) r))
- decodeL :: (Monad m, Binary a) => Parser ByteString m (Either DecodingError (ByteOffset, a))
- decodedL :: (Monad m, Binary a) => Lens' (Producer ByteString m r) (Producer (ByteOffset, a) m (Either (DecodingError, Producer ByteString m r) r))
- decodeGet :: Monad m => Get a -> Parser ByteString m (Either DecodingError a)
- decodeGetL :: Monad m => Get a -> Parser ByteString m (Either DecodingError (ByteOffset, a))
- data DecodingError = DecodingError {
- deConsumed :: !ByteOffset
- deMessage :: !String
- data Word
- class Binary t where
- type Put = PutM ()
- data Get a
- type ByteOffset = Int64
- data Get a
- type Put = PutM ()
- data ByteString
- type Parser a (m :: Type -> Type) r = forall x. StateT (Producer a m x) m r
Encoding
encode :: (Monad m, Binary a) => a -> Proxy x' x () ByteString m () Source #
Convert a value to a byte stream.
encode:: (Monadm,Binarya) => a ->Producer'ByteStringm ()
Keep in mind that a single encode value might be split into many ByteString
chunks, that is, the lenght of the obtained Producer might be greater than
1.
Hint: You can easily turn this Producer' into a Pipe that encodes
Binary instances as they flow downstream using:
forcatencode:: (Monadm,Binarya) =>PipeaByteStringm r
Explicit Put
Decoding
decode :: (Monad m, Binary a) => Parser ByteString m (Either DecodingError a) Source #
Parse a value from a byte stream.
decoded :: (Monad m, Binary a) => Lens' (Producer ByteString m r) (Producer a m (Either (DecodingError, Producer ByteString m r) r)) Source #
Including lengths
decodeL :: (Monad m, Binary a) => Parser ByteString m (Either DecodingError (ByteOffset, a)) Source #
Like decode, but also returns the length of input consumed in order to
to decode the value.
decodedL :: (Monad m, Binary a) => Lens' (Producer ByteString m r) (Producer (ByteOffset, a) m (Either (DecodingError, Producer ByteString m r) r)) Source #
Like decoded, except this tags each decoded value with the length of
input consumed in order to decode it.
Explicit Get
decodeGet :: Monad m => Get a -> Parser ByteString m (Either DecodingError a) Source #
decodeGetL :: Monad m => Get a -> Parser ByteString m (Either DecodingError (ByteOffset, a)) Source #
Types
data DecodingError Source #
Constructors
| DecodingError | |
Fields
| |
Instances
Exports
The following types are re-exported from this module for your convenience:
- From Data.Binary
Binary- From Data.Binary.Put
Put- From Data.Binary.Get
Get,ByteOffset- From Data.ByteString
ByteString- From Pipes.Parse
Parser
Instances
| Data Word | Since: base-4.0.0.0 |
Defined in Data.Data Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Word -> c Word # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Word # dataTypeOf :: Word -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Word) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Word) # gmapT :: (forall b. Data b => b -> b) -> Word -> Word # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Word -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Word -> r # gmapQ :: (forall d. Data d => d -> u) -> Word -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Word -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Word -> m Word # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Word -> m Word # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Word -> m Word # | |
| Bounded Word | Since: base-2.1 |
| Enum Word | Since: base-2.1 |
| Ix Word | Since: base-4.6.0.0 |
| Num Word | Since: base-2.1 |
| Read Word | Since: base-4.5.0.0 |
| Integral Word | Since: base-2.1 |
| Real Word | Since: base-2.1 |
Defined in GHC.Real Methods toRational :: Word -> Rational # | |
| Show Word | Since: base-2.1 |
| Binary Word | |
| Eq Word | |
| Ord Word | |
| Hashable Word | |
Defined in Data.Hashable.Class | |
| IArray UArray Word | |
Defined in Data.Array.Base Methods bounds :: Ix i => UArray i Word -> (i, i) # numElements :: Ix i => UArray i Word -> Int unsafeArray :: Ix i => (i, i) -> [(Int, Word)] -> UArray i Word unsafeAt :: Ix i => UArray i Word -> Int -> Word unsafeReplace :: Ix i => UArray i Word -> [(Int, Word)] -> UArray i Word unsafeAccum :: Ix i => (Word -> e' -> Word) -> UArray i Word -> [(Int, e')] -> UArray i Word unsafeAccumArray :: Ix i => (Word -> e' -> Word) -> Word -> (i, i) -> [(Int, e')] -> UArray i Word | |
| Lift Word | |
| Generic1 (URec Word :: k -> Type) | |
| Foldable (UWord :: TYPE LiftedRep -> Type) | Since: base-4.9.0.0 |
Defined in Data.Foldable Methods fold :: Monoid m => UWord m -> m # foldMap :: Monoid m => (a -> m) -> UWord a -> m # foldMap' :: Monoid m => (a -> m) -> UWord a -> m # foldr :: (a -> b -> b) -> b -> UWord a -> b # foldr' :: (a -> b -> b) -> b -> UWord a -> b # foldl :: (b -> a -> b) -> b -> UWord a -> b # foldl' :: (b -> a -> b) -> b -> UWord a -> b # foldr1 :: (a -> a -> a) -> UWord a -> a # foldl1 :: (a -> a -> a) -> UWord a -> a # elem :: Eq a => a -> UWord a -> Bool # maximum :: Ord a => UWord a -> a # minimum :: Ord a => UWord a -> a # | |
| Traversable (UWord :: Type -> Type) | Since: base-4.9.0.0 |
| MArray (STUArray s) Word (ST s) | |
Defined in Data.Array.Base Methods getBounds :: Ix i => STUArray s i Word -> ST s (i, i) # getNumElements :: Ix i => STUArray s i Word -> ST s Int newArray :: Ix i => (i, i) -> Word -> ST s (STUArray s i Word) # newArray_ :: Ix i => (i, i) -> ST s (STUArray s i Word) # unsafeNewArray_ :: Ix i => (i, i) -> ST s (STUArray s i Word) unsafeRead :: Ix i => STUArray s i Word -> Int -> ST s Word unsafeWrite :: Ix i => STUArray s i Word -> Int -> Word -> ST s () | |
| Functor (URec Word :: TYPE LiftedRep -> Type) | Since: base-4.9.0.0 |
| Generic (URec Word p) | |
| Show (URec Word p) | Since: base-4.9.0.0 |
| Eq (URec Word p) | Since: base-4.9.0.0 |
| Ord (URec Word p) | Since: base-4.9.0.0 |
Defined in GHC.Generics | |
| data URec Word (p :: k) | Used for marking occurrences of Since: base-4.9.0.0 |
| type Rep1 (URec Word :: k -> Type) | Since: base-4.9.0.0 |
Defined in GHC.Generics | |
| type Rep (URec Word p) | Since: base-4.9.0.0 |
Defined in GHC.Generics | |
The Binary class provides put and get, methods to encode and
decode a Haskell value to a lazy ByteString. It mirrors the Read and
Show classes for textual representation of Haskell types, and is
suitable for serialising Haskell values to disk, over the network.
For decoding and generating simple external binary formats (e.g. C
structures), Binary may be used, but in general is not suitable
for complex protocols. Instead use the PutM and Get primitives
directly.
Instances of Binary should satisfy the following property:
decode . encode == id
That is, the get and put methods should be the inverse of each
other. A range of instances are provided for basic Haskell types.
Minimal complete definition
Nothing
Methods
Encode a value in the Put monad.
Decode a value in the Get monad
Encode a list of values in the Put monad. The default implementation may be overridden to be more efficient but must still have the same encoding format.
Instances
| Binary All | Since: binary-0.8.4.0 |
| Binary Any | Since: binary-0.8.4.0 |
| Binary SomeTypeRep | |
Defined in Data.Binary.Class | |
| Binary Version | Since: binary-0.8.0.0 |
| Binary Void | Since: binary-0.8.0.0 |
| Binary Fingerprint | Since: binary-0.7.6.0 |
Defined in Data.Binary.Class | |
| Binary Int16 | |
| Binary Int32 | |
| Binary Int64 | |
| Binary Int8 | |
| Binary Word16 | |
| Binary Word32 | |
| Binary Word64 | |
| Binary Word8 | |
| Binary ByteString | |
Defined in Data.Binary.Class | |
| Binary ByteString | |
Defined in Data.Binary.Class | |
| Binary ShortByteString | |
Defined in Data.Binary.Class Methods put :: ShortByteString -> Put # get :: Get ShortByteString # putList :: [ShortByteString] -> Put # | |
| Binary IntSet | |
| Binary KindRep | Since: binary-0.8.5.0 |
| Binary Ordering | |
| Binary TyCon | Since: binary-0.8.5.0 |
| Binary TypeLitSort | Since: binary-0.8.5.0 |
Defined in Data.Binary.Class | |
| Binary Integer | |
| Binary Natural | Since: binary-0.7.3.0 |
| Binary () | |
| Binary Bool | |
| Binary Char | |
| Binary Double | |
| Binary Float | |
| Binary Int | |
| Binary RuntimeRep | Since: binary-0.8.5.0 |
Defined in Data.Binary.Class | |
| Binary VecCount | Since: binary-0.8.5.0 |
| Binary VecElem | Since: binary-0.8.5.0 |
| Binary Word | |
| Binary a => Binary (Complex a) | |
| Binary a => Binary (Identity a) | |
| Binary a => Binary (First a) | Since: binary-0.8.4.0 |
| Binary a => Binary (Last a) | Since: binary-0.8.4.0 |
| Binary a => Binary (First a) | Since: binary-0.8.4.0 |
| Binary a => Binary (Last a) | Since: binary-0.8.4.0 |
| Binary a => Binary (Max a) | Since: binary-0.8.4.0 |
| Binary a => Binary (Min a) | Since: binary-0.8.4.0 |
| Binary m => Binary (WrappedMonoid m) | Since: binary-0.8.4.0 |
Defined in Data.Binary.Class Methods put :: WrappedMonoid m -> Put # get :: Get (WrappedMonoid m) # putList :: [WrappedMonoid m] -> Put # | |
| Binary a => Binary (Dual a) | Since: binary-0.8.4.0 |
| Binary a => Binary (Product a) | Since: binary-0.8.4.0 |
| Binary a => Binary (Sum a) | Since: binary-0.8.4.0 |
| (Binary a, Integral a) => Binary (Ratio a) | |
| Binary e => Binary (IntMap e) | |
| Binary e => Binary (Seq e) | |
| Binary a => Binary (Set a) | |
| Binary e => Binary (Tree e) | |
| Binary a => Binary (NonEmpty a) | Since: binary-0.8.4.0 |
| Binary a => Binary (Maybe a) | |
| Binary a => Binary [a] | |
| (Binary i, Ix i, Binary e, IArray UArray e) => Binary (UArray i e) | |
| (Binary a, Binary b) => Binary (Either a b) | |
| Binary (Fixed a) | Since: binary-0.8.0.0 |
| (Binary a, Binary b) => Binary (Arg a b) | Since: binary-0.8.4.0 |
| Typeable a => Binary (TypeRep a) | |
| (Binary i, Ix i, Binary e) => Binary (Array i e) | |
| (Binary k, Binary e) => Binary (Map k e) | |
| (Binary a, Binary b) => Binary (a, b) | |
| Binary (f a) => Binary (Alt f a) | Since: binary-0.8.4.0 |
| (Binary a, Binary b, Binary c) => Binary (a, b, c) | |
| (Binary a, Binary b, Binary c, Binary d) => Binary (a, b, c, d) | |
| (Binary a, Binary b, Binary c, Binary d, Binary e) => Binary (a, b, c, d, e) | |
| (Binary a, Binary b, Binary c, Binary d, Binary e, Binary f) => Binary (a, b, c, d, e, f) | |
| (Binary a, Binary b, Binary c, Binary d, Binary e, Binary f, Binary g) => Binary (a, b, c, d, e, f, g) | |
| (Binary a, Binary b, Binary c, Binary d, Binary e, Binary f, Binary g, Binary h) => Binary (a, b, c, d, e, f, g, h) | |
| (Binary a, Binary b, Binary c, Binary d, Binary e, Binary f, Binary g, Binary h, Binary i) => Binary (a, b, c, d, e, f, g, h, i) | |
| (Binary a, Binary b, Binary c, Binary d, Binary e, Binary f, Binary g, Binary h, Binary i, Binary j) => Binary (a, b, c, d, e, f, g, h, i, j) | |
Instances
| MonadFail Get | |
Defined in Data.Binary.Get.Internal | |
| Alternative Get | Since: binary-0.7.0.0 |
| Applicative Get | |
| Functor Get | |
| Monad Get | |
| MonadPlus Get | Since: binary-0.7.1.0 |
type ByteOffset = Int64 #
An offset, counted in bytes.
Instances
| MonadFail Get | |
Defined in Data.Binary.Get.Internal | |
| Alternative Get | Since: binary-0.7.0.0 |
| Applicative Get | |
| Functor Get | |
| Monad Get | |
| MonadPlus Get | Since: binary-0.7.1.0 |
data ByteString #
A space-efficient representation of a Word8 vector, supporting many
efficient operations.
A ByteString contains 8-bit bytes, or by using the operations from
Data.ByteString.Char8 it can be interpreted as containing 8-bit
characters.
Instances
Tutorial
Use encode to convert values to byte streams
-- example.hs
import Pipes
import qualified Pipes.Prelude as P
import Pipes.Binary
readInts :: Int -> Producer Int IO ()
readInts n = P.readLn >-> P.take n
encodedValues :: Producer ByteString IO ()
encodedValues = do
for (readInts 3) encode -- Encode 3 Ints read from user input
encode 'C' -- Encode a 'Char'
encode True -- Encode a 'Bool'Use decode to parse a single decoded value or decoded to access a stream
of decoded values:
-- example.hs
import Data.ByteString (ByteString)
import Pipes.Parse
import Prelude hiding (splitAt)
-- We need to import 'zoom', which can be found in many packages and all work
-- equally fine for our purposes. Read "Pipes.Parse.Tutorial" for details.
--
-- * From the package @lens-family-core@: 'Lens.Family.State.Strict.zoom'
-- * From the package @lens-family@: 'Lens.Family2.State.Strict.zoom'
-- * From the package @lens@: 'Control.Lens.Zoom.zoom'
import Lens.Family.State.Strict (zoom)
decoder :: Parser ByteString IO ()
decoder = do
xs <- zoom (decoded . splitAt 3) drawAll -- Decode up to three 'Int's
lift $ print (xs :: [Int])
y <- decode -- Decode a single 'Char'
lift $ print (y :: Either DecodingError Char)
z <- zoom decoded draw -- Same as 'decode', but
lift $ print (z :: Maybe Bool) -- with a 'Maybe'
main = evalStateT decoder encodedValuesHere are some example inputs:
$ ./example 1<Enter> 2<Enter> 3<Enter> [1,2,3] Right 'C' Just True $ ./example <Ctrl-D> [] Right 'C' Just True