{-# LANGUAGE CPP #-}
{-# LANGUAGE Trustworthy #-}
------------------------------------------------------------------------
-- |
-- Module : Data.HashMap.Lazy
-- Copyright : 2010-2012 Johan Tibell
-- License : BSD-style
-- Maintainer : johan.tibell@gmail.com
-- Stability : provisional
-- Portability : portable
--
-- A map from /hashable/ keys to values. A map cannot contain
-- duplicate keys; each key can map to at most one value. A 'HashMap'
-- makes no guarantees as to the order of its elements.
--
-- The implementation is based on /hash array mapped tries/. A
-- 'HashMap' is often faster than other tree-based set types,
-- especially when key comparison is expensive, as in the case of
-- strings.
--
-- Many operations have a average-case complexity of /O(log n)/. The
-- implementation uses a large base (i.e. 16) so in practice these
-- operations are constant time.
module Data.HashMap.Lazy
(
-- * Strictness properties
-- $strictness
HashMap
-- * Construction
, empty
, singleton
-- * Basic interface
, HM.null
, size
, member
, HM.lookup
, lookupDefault
, (!)
, insert
, insertWith
, delete
, adjust
, update
, alter
-- * Combine
-- ** Union
, union
, unionWith
, unionWithKey
, unions
-- * Transformations
, HM.map
, mapWithKey
, traverseWithKey
-- * Difference and intersection
, difference
, differenceWith
, intersection
, intersectionWith
, intersectionWithKey
-- * Folds
, foldl'
, foldlWithKey'
, HM.foldr
, foldrWithKey
-- * Filter
, HM.filter
, filterWithKey
, mapMaybe
, mapMaybeWithKey
-- * Conversions
, keys
, elems
-- ** Lists
, toList
, fromList
, fromListWith
) where
import Data.HashMap.Base as HM
-- $strictness
--
-- This module satisfies the following strictness property:
--
-- * Key arguments are evaluated to WHNF