Copyright  2011 Bryan O'Sullivan 

License  BSDstyle 
Maintainer  johan.tibell@gmail.com 
Stability  provisional 
Portability  portable 
Safe Haskell  Safe 
Language  Haskell2010 
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 trie. A
HashSet
is often faster than other treebased set types,
especially when value comparison is expensive, as in the case of
strings.
Many operations have a averagecase complexity of O(log n). The implementation uses a large base (i.e. 16) so in practice these operations are constant time.
Synopsis
 data HashSet a
 empty :: HashSet a
 singleton :: Hashable a => a > HashSet a
 union :: (Eq a, Hashable a) => HashSet a > HashSet a > HashSet a
 unions :: (Eq a, Hashable a) => [HashSet 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
 map :: (Hashable b, Eq b) => (a > b) > HashSet a > HashSet b
 difference :: (Eq a, Hashable a) => HashSet a > HashSet a > HashSet a
 intersection :: (Eq a, Hashable a) => HashSet a > HashSet a > HashSet a
 foldl' :: (a > b > a) > a > HashSet b > a
 foldr :: (b > a > 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
Documentation
A set of values. A set cannot contain duplicate values.
Instances
Foldable HashSet Source #  
Defined in Data.HashSet.Base fold :: Monoid m => HashSet m > m # foldMap :: Monoid m => (a > m) > HashSet a > m # foldMap' :: Monoid m => (a > m) > HashSet a > m # foldr :: (a > b > b) > b > HashSet a > b # foldr' :: (a > b > b) > b > HashSet a > b # foldl :: (b > a > b) > b > HashSet a > b # foldl' :: (b > a > b) > b > HashSet a > b # foldr1 :: (a > a > a) > HashSet a > a # foldl1 :: (a > a > a) > HashSet a > a # elem :: Eq a => a > HashSet a > Bool # maximum :: Ord a => HashSet a > a # minimum :: Ord a => HashSet a > a #  
Eq1 HashSet Source #  
Ord1 HashSet Source #  
Defined in Data.HashSet.Base  
Show1 HashSet Source #  
Hashable1 HashSet Source #  
Defined in Data.HashSet.Base  
(Eq a, Hashable a) => IsList (HashSet a) Source #  
Eq a => Eq (HashSet a) Source #  Note that, in the presence of hash collisions, equal
In general, the lack of substitutivity can be observed with any function that depends on the key ordering, such as folds and traversals. 
(Data a, Eq a, Hashable a) => Data (HashSet a) Source #  
Defined in Data.HashSet.Base gfoldl :: (forall d b. Data d => c (d > b) > d > c b) > (forall g. g > c g) > HashSet a > c (HashSet a) # gunfold :: (forall b r. Data b => c (b > r) > c r) > (forall r. r > c r) > Constr > c (HashSet a) # toConstr :: HashSet a > Constr # dataTypeOf :: HashSet a > DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) > Maybe (c (HashSet a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) > Maybe (c (HashSet a)) # gmapT :: (forall b. Data b => b > b) > HashSet a > HashSet a # gmapQl :: (r > r' > r) > r > (forall d. Data d => d > r') > HashSet a > r # gmapQr :: forall r r'. (r' > r > r) > r > (forall d. Data d => d > r') > HashSet a > r # gmapQ :: (forall d. Data d => d > u) > HashSet a > [u] # gmapQi :: Int > (forall d. Data d => d > u) > HashSet a > u # gmapM :: Monad m => (forall d. Data d => d > m d) > HashSet a > m (HashSet a) # gmapMp :: MonadPlus m => (forall d. Data d => d > m d) > HashSet a > m (HashSet a) # gmapMo :: MonadPlus m => (forall d. Data d => d > m d) > HashSet a > m (HashSet a) #  
Ord a => Ord (HashSet a) Source #  
Defined in Data.HashSet.Base  
(Eq a, Hashable a, Read a) => Read (HashSet a) Source #  
Show a => Show (HashSet a) Source #  
(Hashable a, Eq a) => Semigroup (HashSet a) Source #  O(n+m) To obtain good performance, the smaller set must be presented as the first argument. Examples

(Hashable a, Eq a) => Monoid (HashSet a) Source #  O(n+m) To obtain good performance, the smaller set must be presented as the first argument. Examples

NFData a => NFData (HashSet a) Source #  
Defined in Data.HashSet.Base  
Hashable a => Hashable (HashSet a) Source #  
Defined in Data.HashSet.Base  
type Item (HashSet a) Source #  
Defined in Data.HashSet.Base 
Construction
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.
Examples
>>>
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.
Basic interface
insert :: (Eq a, Hashable a) => a > HashSet a > HashSet a Source #
O(log n) Add the specified value to this set.
delete :: (Eq a, Hashable a) => a > HashSet a > HashSet a Source #
O(log n) Remove the specified value from this set if present.
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.
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.
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.
Folds
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 leftidentity 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.
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 rightidentity of the operator).
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.