| Copyright | (c) Lars Brünjes, 2016 |
|---|---|
| License | MIT |
| Maintainer | [email protected] |
| Stability | experimental |
| Portability | portable |
| Safe Haskell | None |
| Language | Haskell2010 |
| Extensions |
|
Data.Utils.List
Description
This module provides various utilities for working with lists.
- splitLast :: [a] -> Maybe ([a], a)
- pick :: Int -> [a] -> (a, [a])
- distribute :: Int -> [a] -> [[a]]
- pad :: Int -> a -> [a] -> [a]
- data ListEditorT a m b
- editListT :: Monad m => ListEditorT a m () -> [a] -> m [a]
- editT :: Monad m => [a] -> ListEditorT a m ()
- tryLeftT :: Monad m => ListEditorT a m Bool
- tryRightT :: Monad m => ListEditorT a m Bool
- focusT :: Monad m => ListEditorT a m [a]
- type ListEditor a = ListEditorT a Identity
- editList :: ListEditor a () -> [a] -> [a]
- pairs :: [a] -> [(a, a)]
- indexOf :: Eq a => [a] -> a -> Maybe Int
Documentation
splitLast :: [a] -> Maybe ([a], a) Source
Splits off the last element of a non-empty list.
>>>splitLast [1, 2, 3]Just ([1,2],3)
>>>splitLast []Nothing
pick :: Int -> [a] -> (a, [a]) Source
Given a valid index, returns the list element at the index and the remaining elements.
>>>pick 1 [1,2,3,4](2,[1,3,4])
distribute :: Int -> [a] -> [[a]] Source
Distributes the elements of a list as uniformly as possible amongst a specified number of groups.
>>>distribute 3 [1,2,3,4,5][[3],[4,1],[5,2]]
pad :: Int -> a -> [a] -> [a] Source
Pads a litst with a provided element on the left.
>>>pad 4 'x' "oo""xxoo"
data ListEditorT a m b Source
ListEditorT a m[a].
Instances
| Monad m => Monad (ListEditorT a m) Source | |
| Functor m => Functor (ListEditorT a m) Source | |
| Monad m => Applicative (ListEditorT a m) Source |
editListT :: Monad m => ListEditorT a m () -> [a] -> m [a] Source
Runs the editor.
editT :: Monad m => [a] -> ListEditorT a m () Source
Replaces the list at the "cursor" with the provided list.
tryLeftT :: Monad m => ListEditorT a m Bool Source
Tries to move the "cursor" to the left.
tryRightT :: Monad m => ListEditorT a m Bool Source
Tries to move the "cursor" to the right.
focusT :: Monad m => ListEditorT a m [a] Source
Gets the list under the "cursor".
type ListEditor a = ListEditorT a Identity Source
Monad for pure list editting.
editList :: ListEditor a () -> [a] -> [a] Source
Runs the pure editor.
>>>editList (do _ <- tryRightT; editT [3,2]) [1,2,3][1,3,2]