Safe Haskell | None |
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Utitlity functions on lists.
- mhead :: [a] -> Maybe a
- uncons :: [a] -> Maybe (a, [a])
- downFrom :: Integral a => a -> [a]
- updateLast :: (a -> a) -> [a] -> [a]
- mapEither :: (a -> Either b c) -> [a] -> ([b], [c])
- deal :: (a -> Either b c) -> a -> ([b], [c]) -> ([b], [c])
- isSublistOf :: Eq a => [a] -> [a] -> Bool
- type Prefix a = [a]
- type Suffix a = [a]
- maybePrefixMatch :: Eq a => Prefix a -> [a] -> Maybe (Suffix a)
- wordsBy :: (a -> Bool) -> [a] -> [[a]]
- chop :: Int -> [a] -> [[a]]
- holes :: [a] -> [(a, [a])]
- sorted :: Ord a => [a] -> Bool
- distinct :: Eq a => [a] -> Bool
- fastDistinct :: Ord a => [a] -> Bool
- prop_distinct_fastDistinct :: [Integer] -> Bool
- allEqual :: Eq a => [a] -> Bool
- groupBy' :: (a -> a -> Bool) -> [a] -> [[a]]
- prop_groupBy' :: (Bool -> Bool -> Bool) -> [Bool] -> Property
- groupOn :: Ord b => (a -> b) -> [a] -> [[a]]
- extractNthElement' :: Integral i => i -> [a] -> ([a], a, [a])
- extractNthElement :: Integral i => i -> [a] -> (a, [a])
- prop_extractNthElement :: Integer -> [Integer] -> Property
- genericElemIndex :: (Eq a, Integral i) => a -> [a] -> Maybe i
- prop_genericElemIndex :: Integer -> [Integer] -> Property
- zipWith' :: (a -> b -> c) -> [a] -> [b] -> [c]
- prop_zipWith' :: (Integer -> Integer -> Integer) -> Property
- zipWithTails :: (a -> b -> c) -> [a] -> [b] -> ([c], [a], [b])
- uniqBy :: Ord b => (a -> b) -> [a] -> [a]
- prop_uniqBy :: [Integer] -> Bool
- tests :: IO Bool
Documentation
updateLast :: (a -> a) -> [a] -> [a]Source
Update the last element of a list, if it exists
mapEither :: (a -> Either b c) -> [a] -> ([b], [c])Source
A generalized version of partition
.
(Cf. mapMaybe
vs. filter
).
isSublistOf :: Eq a => [a] -> [a] -> BoolSource
Sublist relation.
maybePrefixMatch :: Eq a => Prefix a -> [a] -> Maybe (Suffix a)Source
Check if a list has a given prefix. If so, return the list minus the prefix.
wordsBy :: (a -> Bool) -> [a] -> [[a]]Source
Split a list into sublists. Generalisation of the prelude function
words
.
words xs == wordsBy isSpace xs
sorted :: Ord a => [a] -> BoolSource
Check whether a list is sorted.
Assumes that the Ord
instance implements a partial order.
distinct :: Eq a => [a] -> BoolSource
Check whether all elements in a list are distinct from each
other. Assumes that the Eq
instance stands for an equivalence
relation.
fastDistinct :: Ord a => [a] -> BoolSource
allEqual :: Eq a => [a] -> BoolSource
Checks if all the elements in the list are equal. Assumes that
the Eq
instance stands for an equivalence relation.
groupBy' :: (a -> a -> Bool) -> [a] -> [[a]]Source
A variant of groupBy
which applies the predicate to consecutive
pairs.
extractNthElement' :: Integral i => i -> [a] -> ([a], a, [a])Source
gives the extractNthElement
n xsn
-th element in xs
(counting from 0), plus the remaining elements (preserving order).
extractNthElement :: Integral i => i -> [a] -> (a, [a])Source
prop_extractNthElement :: Integer -> [Integer] -> PropertySource
genericElemIndex :: (Eq a, Integral i) => a -> [a] -> Maybe iSource
prop_genericElemIndex :: Integer -> [Integer] -> PropertySource
zipWithTails :: (a -> b -> c) -> [a] -> [b] -> ([c], [a], [b])Source
Like zipWith, but returns the leftover elements of the input lists.
uniqBy :: Ord b => (a -> b) -> [a] -> [a]Source
Efficient version of nub that sorts the list first. The tag function is assumed to be cheap. If it isn't pair up the elements with their tags and call uniqBy fst (or snd).
prop_uniqBy :: [Integer] -> BoolSource