Data.ByteString.Lazy.Internal

bytestring-0.11.1.0: Fast, compact, strict and lazy byte strings with a list interface

Copyright | (c) Don Stewart 2006-2008 (c) Duncan Coutts 2006-2011
License | BSD-style
Maintainer | dons00@gmail.com, duncan@community.haskell.org
Stability | unstable
Portability | non-portable
Safe Haskell | Unsafe
Language | Haskell2010

Data.ByteString.Lazy.Internal

Contents

- The lazy `ByteString` type and representation
- Data type invariant and abstraction function
- Chunk allocation sizes
- Conversion with lists: packing and unpacking
- Conversions with strict ByteString

Description

A module containing semi-public `ByteString` internals. This exposes the `ByteString` representation and low level construction functions. Modules which extend the `ByteString` system will need to use this module while ideally most users will be able to make do with the public interface modules.

Synopsis

- data ByteString
  - = Empty
  - | Chunk !ByteString ByteString
- chunk :: ByteString -> ByteString -> ByteString
- foldrChunks :: (ByteString -> a -> a) -> a -> ByteString -> a
- foldlChunks :: (a -> ByteString -> a) -> a -> ByteString -> a
- invariant :: ByteString -> Bool
- checkInvariant :: ByteString -> ByteString
- defaultChunkSize :: Int
- smallChunkSize :: Int
- chunkOverhead :: Int
- packBytes :: [Word8] -> ByteString
- packChars :: [Char] -> ByteString
- unpackBytes :: ByteString -> [Word8]
- unpackChars :: ByteString -> [Char]
- fromStrict :: ByteString -> ByteString
- toStrict :: ByteString -> ByteString

# The lazy `ByteString` type and representation

data ByteString Source #

A space-efficient representation of a `Word8` vector, supporting many efficient operations.

A lazy `ByteString` contains 8-bit bytes, or by using the operations from Data.ByteString.Lazy.Char8 it can be interpreted as containing 8-bit characters.

Constructors

Empty |
Chunk !ByteString ByteString |

#### Instances

Instances details

Data ByteString # |
Instance details Defined in Data.ByteString.Lazy.Internal Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> ByteString -> c ByteString Source # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c ByteString Source # toConstr :: ByteString -> Constr Source # dataTypeOf :: ByteString -> DataType Source # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c ByteString) Source # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c ByteString) Source # gmapT :: (forall b. Data b => b -> b) -> ByteString -> ByteString Source # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> ByteString -> r Source # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> ByteString -> r Source # gmapQ :: (forall d. Data d => d -> u) -> ByteString -> [u] Source # gmapQi :: Int -> (forall d. Data d => d -> u) -> ByteString -> u Source # gmapM :: Monad m => (forall d. Data d => d -> m d) -> ByteString -> m ByteString Source # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> ByteString -> m ByteString Source # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> ByteString -> m ByteString Source #
IsString ByteString # | Beware: `fromString` truncates multi-byte characters to octets. e.g. "枯朶に烏のとまりけり秋の暮" becomes �6k�nh~�Q��n�
Instance details Defined in Data.ByteString.Lazy.Internal Methods fromString :: String -> ByteString Source #
Monoid ByteString # |
Instance details Defined in Data.ByteString.Lazy.Internal Methods mempty :: ByteString Source # mappend :: ByteString -> ByteString -> ByteString Source # mconcat :: [ByteString] -> ByteString Source #
Semigroup ByteString # |
Instance details Defined in Data.ByteString.Lazy.Internal Methods (<>) :: ByteString -> ByteString -> ByteString Source # sconcat :: NonEmpty ByteString -> ByteString Source # stimes :: Integral b => b -> ByteString -> ByteString Source #
IsList ByteString # | Since: bytestring-0.10.12.0
Instance details Defined in Data.ByteString.Lazy.Internal Associated Types type Item ByteString Source # Methods fromList :: [Item ByteString] -> ByteString Source # fromListN :: Int -> [Item ByteString] -> ByteString Source # toList :: ByteString -> [Item ByteString] Source #
Read ByteString # |
Instance details Defined in Data.ByteString.Lazy.Internal Methods readsPrec :: Int -> ReadS ByteString Source # readList :: ReadS [ByteString] Source # readPrec :: ReadPrec ByteString Source # readListPrec :: ReadPrec [ByteString] Source #
Show ByteString # |
Instance details Defined in Data.ByteString.Lazy.Internal Methods showsPrec :: Int -> ByteString -> ShowS Source # show :: ByteString -> String Source # showList :: [ByteString] -> ShowS Source #
NFData ByteString # |
Instance details Defined in Data.ByteString.Lazy.Internal Methods rnf :: ByteString -> () Source #
Eq ByteString # |
Instance details Defined in Data.ByteString.Lazy.Internal Methods (==) :: ByteString -> ByteString -> Bool Source # (/=) :: ByteString -> ByteString -> Bool Source #
Ord ByteString # |
Instance details Defined in Data.ByteString.Lazy.Internal Methods compare :: ByteString -> ByteString -> Ordering Source # (<) :: ByteString -> ByteString -> Bool Source # (<=) :: ByteString -> ByteString -> Bool Source # (>) :: ByteString -> ByteString -> Bool Source # (>=) :: ByteString -> ByteString -> Bool Source # max :: ByteString -> ByteString -> ByteString Source # min :: ByteString -> ByteString -> ByteString Source #
type Item ByteString # |
Instance details Defined in Data.ByteString.Lazy.Internal type Item ByteString = Word8

chunk :: ByteString -> ByteString -> ByteString Source #

Smart constructor for `Chunk`. Guarantees the data type invariant.

foldrChunks :: (ByteString -> a -> a) -> a -> ByteString -> a Source #

Consume the chunks of a lazy ByteString with a natural right fold.

foldlChunks :: (a -> ByteString -> a) -> a -> ByteString -> a Source #

Consume the chunks of a lazy ByteString with a strict, tail-recursive, accumulating left fold.

# Data type invariant and abstraction function

invariant :: ByteString -> Bool Source #

The data type invariant: Every ByteString is either `Empty` or consists of non-null `ByteString`s. All functions must preserve this, and the QC properties must check this.

checkInvariant :: ByteString -> ByteString Source #

In a form that checks the invariant lazily.

# Chunk allocation sizes

defaultChunkSize :: Int Source #

The chunk size used for I/O. Currently set to 32k, less the memory management overhead

smallChunkSize :: Int Source #

The recommended chunk size. Currently set to 4k, less the memory management overhead

chunkOverhead :: Int Source #

The memory management overhead. Currently this is tuned for GHC only.

# Conversion with lists: packing and unpacking

packBytes :: [Word8] -> ByteString Source #

packChars :: [Char] -> ByteString Source #

unpackBytes :: ByteString -> [Word8] Source #

unpackChars :: ByteString -> [Char] Source #

# Conversions with strict ByteString

fromStrict :: ByteString -> ByteString Source #

O(1) Convert a strict `ByteString` into a lazy `ByteString`.

toStrict :: ByteString -> ByteString Source #

O(n) Convert a lazy `ByteString` into a strict `ByteString`.

Note that this is an expensive operation that forces the whole lazy ByteString into memory and then copies all the data. If possible, try to avoid converting back and forth between strict and lazy bytestrings.