Control.Imperative.Hash

Documentation

A mutable hashtable.

There are two basic operation exported from the Control.Imperative module.

ref

O(1). lookup the value of a hashtable at the given key.

assign

O(1). insert the value at the given key.

Types

data HashTable m k v

Instances

(HashKey k, MHash m) => Indexable (HashTable m k v)

type Element (HashTable m k v) = Ref m v

type IndexType (HashTable m k v) = k

type MonadHash m = (MonadBase (BaseEff m) m, MHash (BaseEff m))

Useful constraint synonym for hashtable operations.

class (Eq k, Hashable k) => HashKey k

Instances

(Eq k, Hashable k) => HashKey k

Operations

new :: MonadHash m => m (HashTable (BaseEff m) k v)

O(1). Create an empty hashtable with a given size.

newSized :: MonadHash m => Int -> m (HashTable (BaseEff m) k v)

O(1). Create an empty hashtable with a given size.

delete :: (HashKey k, MonadHash m) => HashTable (BaseEff m) k v -> k -> m ()

O(n) worst case, O(1) amortized. Delete key-value mapping in a hashtable.

fromList :: (HashKey k, MonadHash m) => [(k, v)] -> m (HashTable (BaseEff m) k v)

O(n). Create a hashtable from an associative list.

toList :: (HashKey k, MonadHash m) => HashTable (BaseEff m) k v -> m [(k, v)]

O(n). Convert the hashtable to a nested associative list.