Unique- It provides the functionality like unix "uniq" utility

Copyright(c) Volodymyr Yashchenko
Safe HaskellSafe



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.



sortUniq :: Ord a => [a] -> [a] Source #

sortUniq sorts the list and removes the duplicates of elements. Example:

sortUniq "foo bar" == " abfor"

isUnique :: Ord a => a -> [a] -> Maybe Bool Source #

isUnique function is to check whether the given element is unique in the list or not.

It returns Nothing when the element does not present in the list. Examples:

isUnique 'f' "foo bar" == Just True
isUnique 'o' "foo bar" == Just False
isUnique '!' "foo bar" == Nothing


isRepeated :: Ord a => a -> [a] -> Maybe Bool Source #

isRepeated is a reverse function to isUnique

Since 0.4.5

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

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] Source #

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] Source #

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

unique  "foo bar" == " abfr"

allUnique :: Ord a => [a] -> Bool Source #

allUnique checks whether all elements of the list are unique

allUnique "foo bar" == False
allUnique ['a'..'z'] == True
allUnique [] == True (!)


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

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)] Source #

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)]