Safe Haskell | None |
---|---|
Language | Haskell2010 |
Internal API for the store package. The functions here which are not re-exported by Data.Store are less likely to have stable APIs.
This module also defines most of the included Store
instances, for
types from the base package and other commonly used packages
(bytestring, containers, text, time, etc).
- encode :: Store a => a -> ByteString
- decode :: Store a => ByteString -> Either PeekException a
- decodeWith :: Peek a -> ByteString -> Either PeekException a
- decodeEx :: Store a => ByteString -> a
- decodeExWith :: Peek a -> ByteString -> a
- decodeExPortionWith :: Peek a -> ByteString -> (Offset, a)
- decodeIO :: Store a => ByteString -> IO a
- decodeIOWith :: Peek a -> ByteString -> IO a
- decodeIOPortionWith :: Peek a -> ByteString -> IO (Offset, a)
- class Store a where
- data Poke a
- data Peek a
- runPeek :: Peek a -> forall byte. Ptr byte -> Ptr byte -> IO (Ptr byte, a)
- data PokeException = PokeException {
- pokeExByteIndex :: Offset
- pokeExMessage :: Text
- pokeException :: Text -> Poke a
- data PeekException = PeekException {
- peekExBytesFromEnd :: Offset
- peekExMessage :: Text
- peekException :: Text -> Peek a
- tooManyBytes :: Int -> Int -> String -> IO void
- data Size a
- getSize :: Store a => a -> Int
- getSizeWith :: Size a -> a -> Int
- contramapSize :: (a -> b) -> Size b -> Size a
- combineSize :: forall a b c. (Store a, Store b) => (c -> a) -> (c -> b) -> Size c
- combineSize' :: forall a b c. (c -> a) -> (c -> b) -> Size a -> Size b -> Size c
- scaleSize :: Int -> Size a -> Size a
- addSize :: Int -> Size a -> Size a
- sizeSequence :: forall t. (IsSequence t, Store (Element t)) => Size t
- pokeSequence :: (IsSequence t, Store (Element t)) => t -> Poke ()
- peekSequence :: (IsSequence t, Store (Element t), Index t ~ Int) => Peek t
- sizeSet :: forall t. (IsSet t, Store (Element t)) => Size t
- pokeSet :: (IsSet t, Store (Element t)) => t -> Poke ()
- peekSet :: (IsSet t, Store (Element t)) => Peek t
- sizeMap :: forall t. (Store (ContainerKey t), Store (MapValue t), IsMap t) => Size t
- pokeMap :: (Store (ContainerKey t), Store (MapValue t), IsMap t) => t -> Poke ()
- peekMap :: (Store (ContainerKey t), Store (MapValue t), IsMap t) => Peek t
- skip :: Int -> Peek ()
- isolate :: Int -> Peek a -> Peek a
- class KnownNat n => IsStaticSize n a where
- toStaticSize :: a -> Maybe (StaticSize n a)
- newtype StaticSize n a = StaticSize {
- unStaticSize :: a
- toStaticSizeEx :: IsStaticSize n a => a -> StaticSize n a
- liftStaticSize :: forall n a. (KnownNat n, Lift a) => TypeQ -> StaticSize n a -> ExpQ
Encoding and decoding strict ByteStrings.
encode :: Store a => a -> ByteString Source
Serializes a value to a ByteString
. In order to do this, it
first allocates a ByteString
of the correct size (based on
size
), and then uses poke
to fill it.
decode :: Store a => ByteString -> Either PeekException a Source
Decodes a value from a ByteString
. Returns an exception if
there's an error while decoding, or if decoding undershoots /
overshoots the end of the buffer.
decodeWith :: Peek a -> ByteString -> Either PeekException a Source
Decodes a value from a ByteString
, potentially throwing
exceptions, and taking a Peek
to run. It is an exception to not
consume all input.
decodeEx :: Store a => ByteString -> a Source
Decodes a value from a ByteString
, potentially throwing
exceptions. It is an exception to not consume all input.
decodeExWith :: Peek a -> ByteString -> a Source
Decodes a value from a ByteString
, potentially throwing
exceptions, and taking a Peek
to run. It is an exception to not
consume all input.
decodeExPortionWith :: Peek a -> ByteString -> (Offset, a) Source
Similar to decodeExWith
, but it allows there to be more of the
buffer remaining. The Offset
of the buffer contents immediately
after the decoded value is returned.
decodeIO :: Store a => ByteString -> IO a Source
Decodes a value from a ByteString
, potentially throwing
exceptions. It is an exception to not consume all input.
decodeIOWith :: Peek a -> ByteString -> IO a Source
Decodes a value from a ByteString
, potentially throwing
exceptions, and taking a Peek
to run. It is an exception to not
consume all input.
decodeIOPortionWith :: Peek a -> ByteString -> IO (Offset, a) Source
Similar to decodeExPortionWith
, but runs in the IO
monad.
Store class and related types.
The Store
typeclass provides efficient serialization and
deserialization to raw pointer addresses.
The peek
and poke
methods should be defined such that
decodeEx (encode x) == x
.
Nothing
Yields the Size
of the buffer, in bytes, required to store
the encoded representation of the type.
Note that the correctness of this function is crucial for the
safety of poke
, as it does not do any bounds checking. It is
the responsibility of the invoker of poke
(encode
and similar
functions) to ensure that there's enough space in the output
buffer. If poke
writes beyond, then arbitrary memory can be
overwritten, causing undefined behavior and segmentation faults.
Serializes a value to bytes. It is the responsibility of the
caller to ensure that at least the number of bytes required by
size
are available. These details are handled by encode
and
similar utilities.
Serialized a value from bytes, throwing exceptions if it encounters invalid data or runs out of input bytes.
Store TypeHash Source | |
(Store a, HasTypeHash a) => Store (Tagged a) Source | |
KnownNat n => Store (StaticSize n ByteString) Source |
Exceptions thrown by Poke
data PokeException Source
Exception thrown while running poke
. Note that other types of
exceptions could also be thrown. Invocations of fail
in the Poke
monad causes this exception to be thrown.
PokeException
s are not expected to occur in ordinary circumstances,
and usually indicate a programming error.
PokeException | |
|
pokeException :: Text -> Poke a Source
Exceptions thrown by Peek
data PeekException Source
Exception thrown while running peek
. Note that other types of
exceptions can also be thrown. Invocations of fail
in the Poke
monad causes this exception to be thrown.
PeekException
is thrown when the data being decoded is invalid.
PeekException | |
|
peekException :: Text -> Peek a Source
Size type
Info about a type's serialized length. Either the length is known independently of the value, or the length depends on the value.
getSizeWith :: Size a -> a -> Int Source
contramapSize :: (a -> b) -> Size b -> Size a Source
combineSize :: forall a b c. (Store a, Store b) => (c -> a) -> (c -> b) -> Size c Source
combineSize' :: forall a b c. (c -> a) -> (c -> b) -> Size a -> Size b -> Size c Source
Store instances in terms of IsSequence
sizeSequence :: forall t. (IsSequence t, Store (Element t)) => Size t Source
Implement size
for an IsSequence
of Store
instances.
Note that many monomorphic containers have more efficient implementations (for example, via memcpy).
pokeSequence :: (IsSequence t, Store (Element t)) => t -> Poke () Source
Implement poke
for an IsSequence
of Store
instances.
Note that many monomorphic containers have more efficient implementations (for example, via memcpy).
peekSequence :: (IsSequence t, Store (Element t), Index t ~ Int) => Peek t Source
Implement peek
for an IsSequence
of Store
instances.
Note that many monomorphic containers have more efficient implementations (for example, via memcpy).
Store instances in terms of IsSet
pokeSet :: (IsSet t, Store (Element t)) => t -> Poke () Source
Implement poke
for an IsSequence
of Store
instances.
peekSet :: (IsSet t, Store (Element t)) => Peek t Source
Implement peek
for an IsSequence
of Store
instances.
Store instances in terms of IsMap
sizeMap :: forall t. (Store (ContainerKey t), Store (MapValue t), IsMap t) => Size t Source
Implement size
for an IsMap
of where both ContainerKey
and
MapValue
are Store
instances.
pokeMap :: (Store (ContainerKey t), Store (MapValue t), IsMap t) => t -> Poke () Source
Implement poke
for an IsMap
of where both ContainerKey
and
MapValue
are Store
instances.
peekMap :: (Store (ContainerKey t), Store (MapValue t), IsMap t) => Peek t Source
Implement peek
for an IsMap
of where both ContainerKey
and
MapValue
are Store
instances.
Peek utilities
isolate :: Int -> Peek a -> Peek a Source
Isolate the input to n bytes, skipping n bytes forward. Fails if m
advances the offset beyond the isolated region.
Static Size type
class KnownNat n => IsStaticSize n a where Source
toStaticSize :: a -> Maybe (StaticSize n a) Source
KnownNat n => IsStaticSize n ByteString Source |
newtype StaticSize n a Source
StaticSize | |
|
Eq a => Eq (StaticSize n a) Source | |
(Data a, Typeable Nat n) => Data (StaticSize n a) Source | |
Ord a => Ord (StaticSize n a) Source | |
Show a => Show (StaticSize n a) Source | |
Generic (StaticSize n a) Source | |
NFData a => NFData (StaticSize n a) Source | |
KnownNat n => Store (StaticSize n ByteString) Source | |
type Rep (StaticSize n a) Source |
toStaticSizeEx :: IsStaticSize n a => a -> StaticSize n a Source
liftStaticSize :: forall n a. (KnownNat n, Lift a) => TypeQ -> StaticSize n a -> ExpQ Source