Cookbook.Ingredients.Lists.Access

Library for accessing the information from a list. Modify and Access are six in one and half-dozen in the other in a purely functional language, but the overall theme is this: Access is for functions which return portions of the list, or information about a list. Modify is the library which transforms a list.

Documentation

count :: Eq a => [a] -> a -> Int

Counts the occurrences an element has within a list.

contains :: Eq a => [a] -> [a] -> Bool

Checks to see if a list is a sub-list of the list.

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

QuickSort implementation. Sorts a list of data quickly?

pull :: [a] -> Int -> Maybe a

Safe implementation of !!. Uses maybe instead of error.

refpos :: Eq a => ([a], [a]) -> a -> a

Referrential positioning. Find the position of an element in the first list, and return the element from the second list of the same position. In the event that the second list is shorter than the position where the element is found in the first list, it returns the parameter.

areAll :: Eq a => [a] -> a -> Bool

Test to make sure that all elements in a list are equal to a value.

isBefore :: Eq a => [a] -> [a] -> Bool

Re-implementation of isPrefixOf for some reason. Tests to see if a list is the first part of antoher list.

surrounds :: Eq a => (a, a) -> [a] -> Bool

Test to see if a list is surrounded by an item.