Safe Haskell	Safe

Hash

Contents

Description

Implementation of fixed-size hash tables, with a type class for constructing hash values for structured types.

Synopsis

The `HashTable` type

data HashTable key val

A hash table with keys of type key and values of type val. The type key should be an instance of Eq.

Operations on `HashTable`s

new :: (Eq key, Hash key) => Int -> IO (HashTable key val)

Builds a new hash table with a given size

insert :: (Eq key, Hash key) => key -> val -> IO ()

Inserts a new element into the hash table

lookup :: Hash key => key -> IO (Maybe val)

Looks up a key in the hash table, returns Just val if the key was found, or Nothing otherwise.

class Hash a where

A class of types which can be hashed.

Methods

hash :: a -> Int

hashes the value of type a into an Int

Instances