Portability | non-portable |
---|---|
Stability | experimental |
Maintainer | Roman Leshchinskiy <rl@cse.unsw.edu.au> |
Mutable vectors based on Storable.
- data MVector s a = MVector !(Ptr a) !Int !(ForeignPtr a)
- type IOVector = MVector RealWorld
- type STVector s = MVector s
- class Storable a
- length :: Storable a => MVector s a -> Int
- overlaps :: Storable a => MVector s a -> MVector s a -> Bool
- slice :: Storable a => Int -> Int -> MVector s a -> MVector s a
- new :: (PrimMonad m, Storable a) => Int -> m (MVector (PrimState m) a)
- newWith :: (PrimMonad m, Storable a) => Int -> a -> m (MVector (PrimState m) a)
- read :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> Int -> m a
- write :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> Int -> a -> m ()
- swap :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> Int -> Int -> m ()
- clear :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> m ()
- set :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> a -> m ()
- copy :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> MVector (PrimState m) a -> m ()
- grow :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> Int -> m (MVector (PrimState m) a)
- unsafeSlice :: Storable a => Int -> Int -> MVector s a -> MVector s a
- unsafeNew :: (PrimMonad m, Storable a) => Int -> m (MVector (PrimState m) a)
- unsafeNewWith :: (PrimMonad m, Storable a) => Int -> a -> m (MVector (PrimState m) a)
- unsafeRead :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> Int -> m a
- unsafeWrite :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> Int -> a -> m ()
- unsafeSwap :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> Int -> Int -> m ()
- unsafeCopy :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> MVector (PrimState m) a -> m ()
- unsafeGrow :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> Int -> m (MVector (PrimState m) a)
- unsafeFromForeignPtr :: Storable a => ForeignPtr a -> Int -> Int -> MVector s a
- unsafeToForeignPtr :: Storable a => MVector s a -> (ForeignPtr a, Int, Int)
- unsafeWith :: Storable a => IOVector a -> (Ptr a -> IO b) -> IO b
Mutable vectors of Storable
types
Mutable Storable
-based vectors
MVector !(Ptr a) !Int !(ForeignPtr a) |
class Storable a
The member functions of this class facilitate writing values of primitive types to raw memory (which may have been allocated with the above mentioned routines) and reading values from blocks of raw memory. The class, furthermore, includes support for computing the storage requirements and alignment restrictions of storable types.
Memory addresses are represented as values of type
, for some
Ptr
aa
which is an instance of class Storable
. The type argument to
Ptr
helps provide some valuable type safety in FFI code (you can't
mix pointers of different types without an explicit cast), while
helping the Haskell type system figure out which marshalling method is
needed for a given pointer.
All marshalling between Haskell and a foreign language ultimately
boils down to translating Haskell data structures into the binary
representation of a corresponding data structure of the foreign
language and vice versa. To code this marshalling in Haskell, it is
necessary to manipulate primitive data types stored in unstructured
memory blocks. The class Storable
facilitates this manipulation on
all types for which it is instantiated, which are the standard basic
types of Haskell, the fixed size Int
types (Int8
, Int16
,
Int32
, Int64
), the fixed size Word
types (Word8
, Word16
,
Word32
, Word64
), StablePtr
, all types from Foreign.C.Types,
as well as Ptr
.
Minimal complete definition: sizeOf
, alignment
, one of peek
,
peekElemOff
and peekByteOff
, and one of poke
, pokeElemOff
and
pokeByteOff
.
Operations on mutable vectors
slice :: Storable a => Int -> Int -> MVector s a -> MVector s aSource
Yield a part of the mutable vector without copying it.
new :: (PrimMonad m, Storable a) => Int -> m (MVector (PrimState m) a)Source
Create a mutable vector of the given length.
newWith :: (PrimMonad m, Storable a) => Int -> a -> m (MVector (PrimState m) a)Source
Create a mutable vector of the given length and fill it with an initial value.
read :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> Int -> m aSource
Yield the element at the given position.
write :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> Int -> a -> m ()Source
Replace the element at the given position.
swap :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> Int -> Int -> m ()Source
Swap the elements at the given positions.
clear :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> m ()Source
Reset all elements of the vector to some undefined value, clearing all references to external objects. This is usually a noop for unboxed vectors.
set :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> a -> m ()Source
Set all elements of the vector to the given value.
copy :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> MVector (PrimState m) a -> m ()Source
Copy a vector. The two vectors must have the same length and may not overlap.
grow :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> Int -> m (MVector (PrimState m) a)Source
Grow a vector by the given number of elements. The number must be positive.
Unsafe operations
Yield a part of the mutable vector without copying it. No bounds checks are performed.
unsafeNew :: (PrimMonad m, Storable a) => Int -> m (MVector (PrimState m) a)Source
Create a mutable vector of the given length. The length is not checked.
unsafeNewWith :: (PrimMonad m, Storable a) => Int -> a -> m (MVector (PrimState m) a)Source
Create a mutable vector of the given length and fill it with an initial value. The length is not checked.
unsafeRead :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> Int -> m aSource
Yield the element at the given position. No bounds checks are performed.
unsafeWrite :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> Int -> a -> m ()Source
Replace the element at the given position. No bounds checks are performed.
unsafeSwap :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> Int -> Int -> m ()Source
Swap the elements at the given positions. No bounds checks are performed.
:: (PrimMonad m, Storable a) | |
=> MVector (PrimState m) a | target |
-> MVector (PrimState m) a | source |
-> m () |
Copy a vector. The two vectors must have the same length and may not overlap. This is not checked.
unsafeGrow :: (PrimMonad m, Storable a) => MVector (PrimState m) a -> Int -> m (MVector (PrimState m) a)Source
Grow a vector by the given number of elements. The number must be positive but this is not checked.
Accessing the underlying memory
:: Storable a | |
=> ForeignPtr a | pointer |
-> Int | offset |
-> Int | length |
-> MVector s a |
Create a mutable vector from a ForeignPtr
with an offset and a length.
Modifying data through the ForeignPtr
afterwards is unsafe if the vector
could have been frozen before the modification.
unsafeToForeignPtr :: Storable a => MVector s a -> (ForeignPtr a, Int, Int)Source
Yield the underlying ForeignPtr
together with the offset to the data
and its length. Modifying the data through the ForeignPtr
is
unsafe if the vector could have frozen before the modification.