primitive-0.6.4.0: Primitive memory-related operations

Copyright(c) 2015 Dan Doel
LicenseBSD3
Maintainerlibraries@haskell.org
Portabilitynon-portable
Safe HaskellNone
LanguageHaskell2010

Data.Primitive.SmallArray

Description

Small arrays are boxed (im)mutable arrays.

The underlying structure of the Array type contains a card table, allowing segments of the array to be marked as having been mutated. This allows the garbage collector to only re-traverse segments of the array that have been marked during certain phases, rather than having to traverse the entire array.

SmallArray lacks this table. This means that it takes up less memory and has slightly faster writes. It is also more efficient during garbage collection so long as the card table would have a single entry covering the entire array. These advantages make them suitable for use as arrays that are known to be small.

The card size is 128, so for uses much larger than that, Array would likely be superior.

The underlying type, SmallArray#, was introduced in GHC 7.10, so prior to that version, this module simply implements small arrays as Array.

Synopsis

Documentation

data SmallArray a #

Constructors

SmallArray (SmallArray# a) 
Instances
Monad SmallArray # 
Instance details

Defined in Data.Primitive.SmallArray

Methods

(>>=) :: SmallArray a -> (a -> SmallArray b) -> SmallArray b #

(>>) :: SmallArray a -> SmallArray b -> SmallArray b #

return :: a -> SmallArray a #

fail :: String -> SmallArray a #

Functor SmallArray # 
Instance details

Defined in Data.Primitive.SmallArray

Methods

fmap :: (a -> b) -> SmallArray a -> SmallArray b #

(<$) :: a -> SmallArray b -> SmallArray a #

MonadFix SmallArray # 
Instance details

Defined in Data.Primitive.SmallArray

Methods

mfix :: (a -> SmallArray a) -> SmallArray a #

Applicative SmallArray # 
Instance details

Defined in Data.Primitive.SmallArray

Methods

pure :: a -> SmallArray a #

(<*>) :: SmallArray (a -> b) -> SmallArray a -> SmallArray b #

liftA2 :: (a -> b -> c) -> SmallArray a -> SmallArray b -> SmallArray c #

(*>) :: SmallArray a -> SmallArray b -> SmallArray b #

(<*) :: SmallArray a -> SmallArray b -> SmallArray a #

Foldable SmallArray # 
Instance details

Defined in Data.Primitive.SmallArray

Methods

fold :: Monoid m => SmallArray m -> m #

foldMap :: Monoid m => (a -> m) -> SmallArray a -> m #

foldr :: (a -> b -> b) -> b -> SmallArray a -> b #

foldr' :: (a -> b -> b) -> b -> SmallArray a -> b #

foldl :: (b -> a -> b) -> b -> SmallArray a -> b #

foldl' :: (b -> a -> b) -> b -> SmallArray a -> b #

foldr1 :: (a -> a -> a) -> SmallArray a -> a #

foldl1 :: (a -> a -> a) -> SmallArray a -> a #

toList :: SmallArray a -> [a] #

null :: SmallArray a -> Bool #

length :: SmallArray a -> Int #

elem :: Eq a => a -> SmallArray a -> Bool #

maximum :: Ord a => SmallArray a -> a #

minimum :: Ord a => SmallArray a -> a #

sum :: Num a => SmallArray a -> a #

product :: Num a => SmallArray a -> a #

Traversable SmallArray # 
Instance details

Defined in Data.Primitive.SmallArray

Methods

traverse :: Applicative f => (a -> f b) -> SmallArray a -> f (SmallArray b) #

sequenceA :: Applicative f => SmallArray (f a) -> f (SmallArray a) #

mapM :: Monad m => (a -> m b) -> SmallArray a -> m (SmallArray b) #

sequence :: Monad m => SmallArray (m a) -> m (SmallArray a) #

Eq1 SmallArray #

Since: 0.6.4.0

Instance details

Defined in Data.Primitive.SmallArray

Methods

liftEq :: (a -> b -> Bool) -> SmallArray a -> SmallArray b -> Bool #

Ord1 SmallArray #

Since: 0.6.4.0

Instance details

Defined in Data.Primitive.SmallArray

Methods

liftCompare :: (a -> b -> Ordering) -> SmallArray a -> SmallArray b -> Ordering #

Read1 SmallArray #

Since: 0.6.4.0

Instance details

Defined in Data.Primitive.SmallArray

Show1 SmallArray #

Since: 0.6.4.0

Instance details

Defined in Data.Primitive.SmallArray

Methods

liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> SmallArray a -> ShowS #

liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [SmallArray a] -> ShowS #

MonadZip SmallArray # 
Instance details

Defined in Data.Primitive.SmallArray

Methods

mzip :: SmallArray a -> SmallArray b -> SmallArray (a, b) #

mzipWith :: (a -> b -> c) -> SmallArray a -> SmallArray b -> SmallArray c #

munzip :: SmallArray (a, b) -> (SmallArray a, SmallArray b) #

Alternative SmallArray # 
Instance details

Defined in Data.Primitive.SmallArray

MonadPlus SmallArray # 
Instance details

Defined in Data.Primitive.SmallArray

IsList (SmallArray a) # 
Instance details

Defined in Data.Primitive.SmallArray

Associated Types

type Item (SmallArray a) :: Type #

Eq a => Eq (SmallArray a) # 
Instance details

Defined in Data.Primitive.SmallArray

Methods

(==) :: SmallArray a -> SmallArray a -> Bool #

(/=) :: SmallArray a -> SmallArray a -> Bool #

Data a => Data (SmallArray a) # 
Instance details

Defined in Data.Primitive.SmallArray

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> SmallArray a -> c (SmallArray a) #

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (SmallArray a) #

toConstr :: SmallArray a -> Constr #

dataTypeOf :: SmallArray a -> DataType #

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (SmallArray a)) #

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (SmallArray a)) #

gmapT :: (forall b. Data b => b -> b) -> SmallArray a -> SmallArray a #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> SmallArray a -> r #

gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> SmallArray a -> r #

gmapQ :: (forall d. Data d => d -> u) -> SmallArray a -> [u] #

gmapQi :: Int -> (forall d. Data d => d -> u) -> SmallArray a -> u #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> SmallArray a -> m (SmallArray a) #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> SmallArray a -> m (SmallArray a) #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> SmallArray a -> m (SmallArray a) #

Ord a => Ord (SmallArray a) #

Lexicographic ordering. Subject to change between major versions.

Instance details

Defined in Data.Primitive.SmallArray

Read a => Read (SmallArray a) # 
Instance details

Defined in Data.Primitive.SmallArray

Show a => Show (SmallArray a) # 
Instance details

Defined in Data.Primitive.SmallArray

Semigroup (SmallArray a) #

Since: 0.6.3.0

Instance details

Defined in Data.Primitive.SmallArray

Monoid (SmallArray a) # 
Instance details

Defined in Data.Primitive.SmallArray

PrimUnlifted (SmallArray a) # 
Instance details

Defined in Data.Primitive.UnliftedArray

type Item (SmallArray a) # 
Instance details

Defined in Data.Primitive.SmallArray

type Item (SmallArray a) = a

data SmallMutableArray s a #

Instances
Eq (SmallMutableArray s a) # 
Instance details

Defined in Data.Primitive.SmallArray

(Typeable s, Typeable a) => Data (SmallMutableArray s a) # 
Instance details

Defined in Data.Primitive.SmallArray

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> SmallMutableArray s a -> c (SmallMutableArray s a) #

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (SmallMutableArray s a) #

toConstr :: SmallMutableArray s a -> Constr #

dataTypeOf :: SmallMutableArray s a -> DataType #

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (SmallMutableArray s a)) #

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (SmallMutableArray s a)) #

gmapT :: (forall b. Data b => b -> b) -> SmallMutableArray s a -> SmallMutableArray s a #

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> SmallMutableArray s a -> r #

gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> SmallMutableArray s a -> r #

gmapQ :: (forall d. Data d => d -> u) -> SmallMutableArray s a -> [u] #

gmapQi :: Int -> (forall d. Data d => d -> u) -> SmallMutableArray s a -> u #

gmapM :: Monad m => (forall d. Data d => d -> m d) -> SmallMutableArray s a -> m (SmallMutableArray s a) #

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> SmallMutableArray s a -> m (SmallMutableArray s a) #

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> SmallMutableArray s a -> m (SmallMutableArray s a) #

PrimUnlifted (SmallMutableArray s a) # 
Instance details

Defined in Data.Primitive.UnliftedArray

newSmallArray #

Arguments

:: PrimMonad m 
=> Int

size

-> a

initial contents

-> m (SmallMutableArray (PrimState m) a) 

Create a new small mutable array.

readSmallArray #

Arguments

:: PrimMonad m 
=> SmallMutableArray (PrimState m) a

array

-> Int

index

-> m a 

Read the element at a given index in a mutable array.

writeSmallArray #

Arguments

:: PrimMonad m 
=> SmallMutableArray (PrimState m) a

array

-> Int

index

-> a

new element

-> m () 

Write an element at the given idex in a mutable array.

copySmallArray #

Arguments

:: PrimMonad m 
=> SmallMutableArray (PrimState m) a

destination

-> Int

destination offset

-> SmallArray a

source

-> Int

source offset

-> Int

length

-> m () 

Copy a slice of an immutable array into a mutable array.

copySmallMutableArray #

Arguments

:: PrimMonad m 
=> SmallMutableArray (PrimState m) a

destination

-> Int

destination offset

-> SmallMutableArray (PrimState m) a

source

-> Int

source offset

-> Int

length

-> m () 

Copy a slice of one mutable array into another.

indexSmallArray #

Arguments

:: SmallArray a

array

-> Int

index

-> a 

Look up an element in an immutable array.

indexSmallArrayM #

Arguments

:: Monad m 
=> SmallArray a

array

-> Int

index

-> m a 

Look up an element in an immutable array.

The purpose of returning a result using a monad is to allow the caller to avoid retaining references to the array. Evaluating the return value will cause the array lookup to be performed, even though it may not require the element of the array to be evaluated (which could throw an exception). For instance:

data Box a = Box a
...

f sa = case indexSmallArrayM sa 0 of
  Box x -> ...

x is not a closure that references sa as it would be if we instead wrote:

let x = indexSmallArray sa 0

And does not prevent sa from being garbage collected.

Note that Identity is not adequate for this use, as it is a newtype, and cannot be evaluated without evaluating the element.

indexSmallArray## :: SmallArray a -> Int -> (#a#) #

Read a value from the immutable array at the given index, returning the result in an unboxed unary tuple. This is currently used to implement folds.

cloneSmallArray #

Arguments

:: SmallArray a

source

-> Int

offset

-> Int

length

-> SmallArray a 

Create a copy of a slice of an immutable array.

cloneSmallMutableArray #

Arguments

:: PrimMonad m 
=> SmallMutableArray (PrimState m) a

source

-> Int

offset

-> Int

length

-> m (SmallMutableArray (PrimState m) a) 

Create a copy of a slice of a mutable array.

freezeSmallArray #

Arguments

:: PrimMonad m 
=> SmallMutableArray (PrimState m) a

source

-> Int

offset

-> Int

length

-> m (SmallArray a) 

Create an immutable array corresponding to a slice of a mutable array.

This operation copies the portion of the array to be frozen.

unsafeFreezeSmallArray :: PrimMonad m => SmallMutableArray (PrimState m) a -> m (SmallArray a) #

Render a mutable array immutable.

This operation performs no copying, so care must be taken not to modify the input array after freezing.

thawSmallArray #

Arguments

:: PrimMonad m 
=> SmallArray a

source

-> Int

offset

-> Int

length

-> m (SmallMutableArray (PrimState m) a) 

Create a mutable array corresponding to a slice of an immutable array.

This operation copies the portion of the array to be thawed.

runSmallArray :: (forall s. ST s (SmallMutableArray s a)) -> SmallArray a #

unsafeThawSmallArray :: PrimMonad m => SmallArray a -> m (SmallMutableArray (PrimState m) a) #

Render an immutable array mutable.

This operation performs no copying, so care must be taken with its use.

smallArrayFromList :: [a] -> SmallArray a #

Create a SmallArray from a list.

smallArrayFromListN :: Int -> [a] -> SmallArray a #

Create a SmallArray from a list of a known length. If the length of the list does not match the given length, this throws an exception.

mapSmallArray' :: (a -> b) -> SmallArray a -> SmallArray b #

Strict map over the elements of the array.

traverseSmallArrayP :: PrimMonad m => (a -> m b) -> SmallArray a -> m (SmallArray b) #

This is the fastest, most straightforward way to traverse an array, but it only works correctly with a sufficiently "affine" PrimMonad instance. In particular, it must only produce *one* result array. ListT-transformed monads, for example, will not work right at all.