Data.List.UniqueStrict

Library provides functions to find unique and duplicate elements in the list. Unlike Data.List.Unique this one uses Data.Map.Strict for calculations. So it's much faster and it uses less memory.

Documentation

repeated :: Ord a => [a] -> [a]

repeated finds only the elements that are present more than once in the list. Example:

repeated  "foo bar" == "o" 

repeatedBy :: Ord a => (Int -> Bool) -> [a] -> [a]

The repeatedBy function behaves just like repeated, except it uses a user-supplied equality predicate.

repeatedBy (>2) "This is the test line" == " eist"

unique :: Ord a => [a] -> [a]

unique gets only unique elements, that do not have duplicates. It sorts them. Example:

unique  "foo bar" == " abfr"

count :: Ord a => [a] -> [(a, Int)]

count of each element in the list, it sorts by keys (elements). Example:

count "foo bar" == [(' ',1),('a',1),('b',1),('f',1),('o',2),('r',1)]

count_ :: Ord a => [a] -> [(a, Int)]

count_ of each elements in the list, it sorts by their number. Example:

count_ "foo bar" == [(' ',1),('a',1),('b',1),('f',1),('r',1),('o',2)]