Copyright	2011 Bryan O'Sullivan
License	BSD-style
Maintainer	johan.tibell@gmail.com
Portability	portable
Safe Haskell	Trustworthy
Language	Haskell2010

Data.HashSet.Internal

Contents

Construction
Basic interface
Transformations
Combine
Difference and intersection
Folds
Filter
Conversions
- Lists
HashMaps

Description

WARNING

This module is considered internal .

The Package Versioning Policy does not apply .

The contents of this module may change in any way whatsoever and without any warning between minor versions of this package.

Authors importing this module are expected to track development closely.

Description

A set of hashable values. A set cannot contain duplicate items. A HashSet makes no guarantees as to the order of its elements.

The implementation is based on hash array mapped tries . A HashSet is often faster than other tree-based set types, especially when value 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. 32) so in practice these operations are constant time.

Synopsis

newtype HashSet a = HashSet {
- asMap :: HashMap a ()
}
empty :: HashSet a
singleton :: Hashable a => a -> HashSet a
null :: HashSet a -> Bool
size :: HashSet a -> Int
member :: ( Eq a, Hashable a) => a -> HashSet a -> Bool
insert :: ( Eq a, Hashable a) => a -> HashSet a -> HashSet a
delete :: ( Eq a, Hashable a) => a -> HashSet a -> HashSet a
isSubsetOf :: ( Eq a, Hashable a) => HashSet a -> HashSet a -> Bool
map :: ( Hashable b, Eq b) => (a -> b) -> HashSet a -> HashSet b
union :: ( Eq a, Hashable a) => HashSet a -> HashSet a -> HashSet a
unions :: ( Eq a, Hashable a) => [ HashSet a] -> HashSet a
difference :: ( Eq a, Hashable a) => HashSet a -> HashSet a -> HashSet a
intersection :: ( Eq a, Hashable a) => HashSet a -> HashSet a -> HashSet a
foldr :: (b -> a -> a) -> a -> HashSet b -> a
foldr' :: (b -> a -> a) -> a -> HashSet b -> a
foldl :: (a -> b -> a) -> a -> HashSet b -> a
foldl' :: (a -> b -> a) -> a -> HashSet b -> a
filter :: (a -> Bool ) -> HashSet a -> HashSet a
toList :: HashSet a -> [a]
fromList :: ( Eq a, Hashable a) => [a] -> HashSet a
toMap :: HashSet a -> HashMap a ()
fromMap :: HashMap a () -> HashSet a
keysSet :: HashMap k a -> HashSet k

Documentation

newtype HashSet a Source #

A set of values. A set cannot contain duplicate values.

Constructors

HashSet
Fields asMap :: HashMap a ()

Instances

Instances details

Foldable HashSet Source #
Instance details Defined in Data.HashSet.Internal Methods fold :: Monoid m => HashSet m -> m Source # foldMap :: Monoid m => (a -> m) -> HashSet a -> m Source # foldMap' :: Monoid m => (a -> m) -> HashSet a -> m Source # foldr :: (a -> b -> b) -> b -> HashSet a -> b Source # foldr' :: (a -> b -> b) -> b -> HashSet a -> b Source # foldl :: (b -> a -> b) -> b -> HashSet a -> b Source # foldl' :: (b -> a -> b) -> b -> HashSet a -> b Source # foldr1 :: (a -> a -> a) -> HashSet a -> a Source # foldl1 :: (a -> a -> a) -> HashSet a -> a Source # toList :: HashSet a -> [a] Source # null :: HashSet a -> Bool Source # length :: HashSet a -> Int Source # elem :: Eq a => a -> HashSet a -> Bool Source # maximum :: Ord a => HashSet a -> a Source # minimum :: Ord a => HashSet a -> a Source # sum :: Num a => HashSet a -> a Source # product :: Num a => HashSet a -> a Source #
Eq1 HashSet Source #
Instance details Defined in Data.HashSet.Internal Methods liftEq :: (a -> b -> Bool ) -> HashSet a -> HashSet b -> Bool Source #
Ord1 HashSet Source #
Instance details Defined in Data.HashSet.Internal Methods liftCompare :: (a -> b -> Ordering ) -> HashSet a -> HashSet b -> Ordering Source #
Show1 HashSet Source #
Instance details Defined in Data.HashSet.Internal Methods liftShowsPrec :: ( Int -> a -> ShowS ) -> ([a] -> ShowS ) -> Int -> HashSet a -> ShowS Source # liftShowList :: ( Int -> a -> ShowS ) -> ([a] -> ShowS ) -> [ HashSet a] -> ShowS Source #
NFData1 HashSet Source #	Since: 0.2.14.0
Instance details Defined in Data.HashSet.Internal Methods liftRnf :: (a -> ()) -> HashSet a -> () Source #
Hashable1 HashSet Source #
Instance details Defined in Data.HashSet.Internal Methods liftHashWithSalt :: ( Int -> a -> Int ) -> Int -> HashSet a -> Int Source #
Lift a => Lift ( HashSet a :: Type ) Source #	Since: 0.2.17.0
Instance details Defined in Data.HashSet.Internal Methods lift :: HashSet a -> Q Exp Source # liftTyped :: HashSet a -> Q ( TExp ( HashSet a)) Source #
( Eq a, Hashable a) => IsList ( HashSet a) Source #
Instance details Defined in Data.HashSet.Internal Associated Types type Item ( HashSet a) Source # Methods fromList :: [ Item ( HashSet a)] -> HashSet a Source # fromListN :: Int -> [ Item ( HashSet a)] -> HashSet a Source # toList :: HashSet a -> [ Item ( HashSet a)] Source #
Eq a => Eq ( HashSet a) Source #	Note that, in the presence of hash collisions, equal `HashSet` s may behave differently, i.e. substitutivity may be violated: `>>>` `data D = A \| B deriving (Eq, Show)``>>>` `instance Hashable D where hashWithSalt salt _d = salt` `>>>` `x = fromList [A, B]``>>>` `y = fromList [B, A]` `>>>` `x == y`True `>>>` `toList x`[A,B] `>>>` `toList y`[B,A] In general, the lack of substitutivity can be observed with any function that depends on the key ordering, such as folds and traversals.
Instance details Defined in Data.HashSet.Internal Methods (==) :: HashSet a -> HashSet a -> Bool Source # (/=) :: HashSet a -> HashSet a -> Bool Source #
( Data a, Eq a, Hashable a) => Data ( HashSet a) Source #
Instance details Defined in Data.HashSet.Internal Methods gfoldl :: ( forall d b. Data d => c (d -> b) -> d -> c b) -> ( forall g. g -> c g) -> HashSet a -> c ( HashSet a) Source # gunfold :: ( forall b r. Data b => c (b -> r) -> c r) -> ( forall r. r -> c r) -> Constr -> c ( HashSet a) Source # toConstr :: HashSet a -> Constr Source # dataTypeOf :: HashSet a -> DataType Source # dataCast1 :: Typeable t => ( forall d. Data d => c (t d)) -> Maybe (c ( HashSet a)) Source # dataCast2 :: Typeable t => ( forall d e. ( Data d, Data e) => c (t d e)) -> Maybe (c ( HashSet a)) Source # gmapT :: ( forall b. Data b => b -> b) -> HashSet a -> HashSet a Source # gmapQl :: (r -> r' -> r) -> r -> ( forall d. Data d => d -> r') -> HashSet a -> r Source # gmapQr :: forall r r'. (r' -> r -> r) -> r -> ( forall d. Data d => d -> r') -> HashSet a -> r Source # gmapQ :: ( forall d. Data d => d -> u) -> HashSet a -> [u] Source # gmapQi :: Int -> ( forall d. Data d => d -> u) -> HashSet a -> u Source # gmapM :: Monad m => ( forall d. Data d => d -> m d) -> HashSet a -> m ( HashSet a) Source # gmapMp :: MonadPlus m => ( forall d. Data d => d -> m d) -> HashSet a -> m ( HashSet a) Source # gmapMo :: MonadPlus m => ( forall d. Data d => d -> m d) -> HashSet a -> m ( HashSet a) Source #
Ord a => Ord ( HashSet a) Source #
Instance details Defined in Data.HashSet.Internal Methods compare :: HashSet a -> HashSet a -> Ordering Source # (<) :: HashSet a -> HashSet a -> Bool Source # (<=) :: HashSet a -> HashSet a -> Bool Source # (>) :: HashSet a -> HashSet a -> Bool Source # (>=) :: HashSet a -> HashSet a -> Bool Source # max :: HashSet a -> HashSet a -> HashSet a Source # min :: HashSet a -> HashSet a -> HashSet a Source #
( Eq a, Hashable a, Read a) => Read ( HashSet a) Source #
Instance details Defined in Data.HashSet.Internal Methods readsPrec :: Int -> ReadS ( HashSet a) Source # readList :: ReadS [ HashSet a] Source # readPrec :: ReadPrec ( HashSet a) Source # readListPrec :: ReadPrec [ HashSet a] Source #
Show a => Show ( HashSet a) Source #
Instance details Defined in Data.HashSet.Internal Methods showsPrec :: Int -> HashSet a -> ShowS Source # show :: HashSet a -> String Source # showList :: [ HashSet a] -> ShowS Source #
( Hashable a, Eq a) => Semigroup ( HashSet a) Source #	`<>` = `union` \(O(n+m)\) To obtain good performance, the smaller set must be presented as the first argument. Examples Expand `>>>` `fromList [1,2] <> fromList [2,3]`fromList [1,2,3]
Instance details Defined in Data.HashSet.Internal Methods (<>) :: HashSet a -> HashSet a -> HashSet a Source # sconcat :: NonEmpty ( HashSet a) -> HashSet a Source # stimes :: Integral b => b -> HashSet a -> HashSet a Source #
( Hashable a, Eq a) => Monoid ( HashSet a) Source #	`mempty` = `empty` `mappend` = `union` \(O(n+m)\) To obtain good performance, the smaller set must be presented as the first argument. Examples Expand `>>>` `mappend (fromList [1,2]) (fromList [2,3])`fromList [1,2,3]
Instance details Defined in Data.HashSet.Internal Methods mempty :: HashSet a Source # mappend :: HashSet a -> HashSet a -> HashSet a Source # mconcat :: [ HashSet a] -> HashSet a Source #
NFData a => NFData ( HashSet a) Source #
Instance details Defined in Data.HashSet.Internal Methods rnf :: HashSet a -> () Source #
Hashable a => Hashable ( HashSet a) Source #
Instance details Defined in Data.HashSet.Internal Methods hashWithSalt :: Int -> HashSet a -> Int Source # hash :: HashSet a -> Int Source #
type Item ( HashSet a) Source #
Instance details Defined in Data.HashSet.Internal type Item ( HashSet a) = a

Construction

empty :: HashSet a Source #

\(O(1)\) Construct an empty set.

>>> HashSet.empty
fromList []

singleton :: Hashable a => a -> HashSet a Source #

\(O(1)\) Construct a set with a single element.

>>> HashSet.singleton 1
fromList [1]

Basic interface

null :: HashSet a -> Bool Source #

\(O(1)\) Return True if this set is empty, False otherwise.

>>> HashSet.null HashSet.empty
True
>>> HashSet.null (HashSet.singleton 1)
False

size :: HashSet a -> Int Source #

\(O(n)\) Return the number of elements in this set.

>>> HashSet.size HashSet.empty
0
>>> HashSet.size (HashSet.fromList [1,2,3])
3

member :: ( Eq a, Hashable a) => a -> HashSet a -> Bool Source #

\(O(\log n)\) Return True if the given value is present in this set, False otherwise.

>>> HashSet.member 1 (Hashset.fromList [1,2,3])
True
>>> HashSet.member 1 (Hashset.fromList [4,5,6])
False

insert :: ( Eq a, Hashable a) => a -> HashSet a -> HashSet a Source #

\(O(\log n)\) Add the specified value to this set.

>>> HashSet.insert 1 HashSet.empty
fromList [1]

delete :: ( Eq a, Hashable a) => a -> HashSet a -> HashSet a Source #

\(O(\log n)\) Remove the specified value from this set if present.

>>> HashSet.delete 1 (HashSet.fromList [1,2,3])
fromList [2,3]
>>> HashSet.delete 1 (HashSet.fromList [4,5,6])
fromList [4,5,6]

isSubsetOf :: ( Eq a, Hashable a) => HashSet a -> HashSet a -> Bool Source #

\(O(n \log m)\) Inclusion of sets.

Examples

Expand

>>> fromList [1,3] `isSubsetOf` fromList [1,2,3]
True

>>> fromList [1,2] `isSubsetOf` fromList [1,3]
False

Since: 0.2.12

Transformations

map :: ( Hashable b, Eq b) => (a -> b) -> HashSet a -> HashSet b Source #

\(O(n)\) Transform this set by applying a function to every value. The resulting set may be smaller than the source.

>>> HashSet.map show (HashSet.fromList [1,2,3])
HashSet.fromList ["1","2","3"]

Combine

union :: ( Eq a, Hashable a) => HashSet a -> HashSet a -> HashSet a Source #

\(O(n+m)\) Construct a set containing all elements from both sets.

To obtain good performance, the smaller set must be presented as the first argument.

>>> union (fromList [1,2]) (fromList [2,3])
fromList [1,2,3]

unions :: ( Eq a, Hashable a) => [ HashSet a] -> HashSet a Source #

Construct a set containing all elements from a list of sets.

Difference and intersection

difference :: ( Eq a, Hashable a) => HashSet a -> HashSet a -> HashSet a Source #

\(O(n)\) Difference of two sets. Return elements of the first set not existing in the second.

>>> HashSet.difference (HashSet.fromList [1,2,3]) (HashSet.fromList [2,3,4])
fromList [1]

intersection :: ( Eq a, Hashable a) => HashSet a -> HashSet a -> HashSet a Source #

\(O(n)\) Intersection of two sets. Return elements present in both the first set and the second.

>>> HashSet.intersection (HashSet.fromList [1,2,3]) (HashSet.fromList [2,3,4])
fromList [2,3]

Folds

foldr :: (b -> a -> a) -> a -> HashSet b -> a Source #

\(O(n)\) Reduce this set by applying a binary operator to all elements, using the given starting value (typically the right-identity of the operator).

foldr' :: (b -> a -> a) -> a -> HashSet b -> a Source #

\(O(n)\) Reduce this set by applying a binary operator to all elements, using the given starting value (typically the right-identity of the operator). Each application of the operator is evaluated before before using the result in the next application. This function is strict in the starting value.

foldl :: (a -> b -> a) -> a -> HashSet b -> a Source #

\(O(n)\) Reduce this set by applying a binary operator to all elements, using the given starting value (typically the left-identity of the operator).

foldl' :: (a -> b -> a) -> a -> HashSet b -> a Source #

\(O(n)\) Reduce this set by applying a binary operator to all elements, using the given starting value (typically the left-identity of the operator). Each application of the operator is evaluated before before using the result in the next application. This function is strict in the starting value.

Filter

filter :: (a -> Bool ) -> HashSet a -> HashSet a Source #

\(O(n)\) Filter this set by retaining only elements satisfying a predicate.

Conversions

Lists

toList :: HashSet a -> [a] Source #

\(O(n)\) Return a list of this set's elements. The list is produced lazily.

fromList :: ( Eq a, Hashable a) => [a] -> HashSet a Source #

\(O(n \min(W, n))\) Construct a set from a list of elements.

HashMaps

toMap :: HashSet a -> HashMap a () Source #

\(O(1)\) Convert to set to the equivalent HashMap with () values.

>>> HashSet.toMap (HashSet.singleton 1)
fromList [(1,())]

fromMap :: HashMap a () -> HashSet a Source #

\(O(1)\) Convert from the equivalent HashMap with () values.

>>> HashSet.fromMap (HashMap.singleton 1 ())
fromList [1]

keysSet :: HashMap k a -> HashSet k Source #

\(O(n)\) Produce a HashSet of all the keys in the given HashMap .

>>> HashSet.keysSet (HashMap.fromList [(1, "a"), (2, "b")]
fromList [1,2]

Since: 0.2.10.0