Portability | portable |
---|---|
Stability | provisional |
Maintainer | Edward Kmett <ekmett@gmail.com> |
Safe Haskell | Safe-Infered |
Traversals for manipulating parts of a list.
- _head :: Simple Lens [a] a
- _tail :: Simple Lens [a] [a]
- _last :: Simple Lens [a] a
- _init :: Simple Lens [a] [a]
- interspersed :: a -> Getter [a] [a]
- intercalated :: [a] -> Getter [[a]] [a]
- traverseHead :: SimpleTraversal [a] a
- traverseTail :: SimpleTraversal [a] a
- traverseInit :: SimpleTraversal [a] a
- traverseLast :: SimpleTraversal [a] a
Documentation
_head :: Simple Lens [a] aSource
A lens reading and writing to the head of a non-empty list
ghci> [1,2,3]^._head 1
_tail :: Simple Lens [a] [a]Source
A lens reading and writing to the tail of a non-empty list
ghci> _tail <~ [3,4,5] $ [1,2] [1,3,4,5]
_init :: Simple Lens [a] [a]Source
A lens reading and replacing all but the a last element of a non-empty list
interspersed :: a -> Getter [a] [a]Source
Obtain a version of the list with the supplied value interspersed.
ghci> "abcde"^.interspersed ',' "a,b,c,d,e"
xs^.interspersed a = intersperse a xs
intercalated :: [a] -> Getter [[a]] [a]Source
Obtain a version of the list with the supplied value intercalated
traverseHead :: SimpleTraversal [a] aSource
The traversal for reading and writing to the head of a list
traverseHead :: Applicative f => (a -> f a) -> [a] -> f [a]
traverseTail :: SimpleTraversal [a] aSource
Traversal for editing the tail of a list.
traverseTail :: Applicative f => (a -> f a) -> [a] -> f [a]
traverseInit :: SimpleTraversal [a] aSource
Traverse all but the last element of a list
traverseInit :: Applicative f => (a -> f a) -> [a] -> f [a]
traverseLast :: SimpleTraversal [a] aSource
Traverse the last element in a list.
traverseLast :: Applicative f => (a -> f a) -> [a] -> f [a]