Data.Array.ST

data STArray :: Region -> Type -> Type

A reference to a mutable array.

The first type parameter represents the memory region which the array belongs to. The second type parameter defines the type of elements of the mutable array.

The runtime representation of a value of type STArray h a is the same as that of Array a, except that mutation is allowed.

type Assoc a = { index :: Int, value :: a }

An element and its index.

run :: forall a. (forall h. ST h (STArray h a)) -> Array a

A safe way to create and work with a mutable array before returning an immutable array for later perusal. This function avoids copying the array before returning it - it uses unsafeFreeze internally, but this wrapper is a safe interface to that function.

withArray :: forall h a b. (STArray h a -> ST h b) -> Array a -> ST h (Array a)

Perform an effect requiring a mutable array on a copy of an immutable array, safely returning the result as an immutable array.

empty :: forall h a. ST h (STArray h a)

Create an empty mutable array.

peek :: forall h a. Int -> STArray h a -> ST h (Maybe a)

Read the value at the specified index in a mutable array.

poke :: forall h a. Int -> a -> STArray h a -> ST h Boolean

Change the value at the specified index in a mutable array.

modify :: forall h a. Int -> (a -> a) -> STArray h a -> ST h Boolean

Mutate the element at the specified index using the supplied function.

pop :: forall h a. STArray h a -> ST h (Maybe a)

Remove the last element from an array and return that element.

push :: forall h a. a -> STArray h a -> ST h Int

Append an element to the end of a mutable array. Returns the new length of the array.

pushAll :: forall h a. Array a -> STArray h a -> ST h Int

Append the values in an immutable array to the end of a mutable array. Returns the new length of the mutable array.

shift :: forall h a. STArray h a -> ST h (Maybe a)

Remove the first element from an array and return that element.

unshift :: forall h a. a -> STArray h a -> ST h Int

Append an element to the front of a mutable array. Returns the new length of the array.

unshiftAll :: forall h a. Array a -> STArray h a -> ST h Int

Append the values in an immutable array to the front of a mutable array. Returns the new length of the mutable array.

splice :: forall h a. Int -> Int -> Array a -> STArray h a -> ST h (Array a)

Remove and/or insert elements from/into a mutable array at the specified index.

sort :: forall a h. Ord a => STArray h a -> ST h (STArray h a)

Sort a mutable array in place.

sortBy :: forall a h. (a -> a -> Ordering) -> STArray h a -> ST h (STArray h a)

Sort a mutable array in place using a comparison function.

sortWith :: forall a b h. Ord b => (a -> b) -> STArray h a -> ST h (STArray h a)

Sort a mutable array in place based on a projection.

freeze :: forall h a. STArray h a -> ST h (Array a)

Create an immutable copy of a mutable array.

thaw :: forall h a. Array a -> ST h (STArray h a)

Create a mutable copy of an immutable array.

unsafeFreeze :: forall h a. STArray h a -> ST h (Array a)

O(1). Convert a mutable array to an immutable array, without copying. The mutable array must not be mutated afterwards.

unsafeThaw :: forall h a. Array a -> ST h (STArray h a)

O(1) Convert an immutable array to a mutable array, without copying. The input array must not be used afterward.

toAssocArray :: forall h a. STArray h a -> ST h (Array (Assoc a))

Create an immutable copy of a mutable array, where each element is labelled with its index in the original array.