map -package:containers -package:bytestring -package:base-compat-batteries -package:incipit-base -package:case-insensitive -package:Cabal-syntax -package:insert-ordered-containers -package:blaze-html -package:charset -package:os-string -package:basement -package:aeson -package:ghc -package:dlist -package:conduit -package:imports -package:vector -package:hedgehog -package:dense-linear-algebra -package:invertible -package:pipes -package:integration -package:text

map f xs is the list obtained by applying f to each element of xs, i.e.,

map f [x1, x2, ..., xn] == [f x1, f x2, ..., f xn]
map f [x1, x2, ...] == [f x1, f x2, ...]

>>> map (+1) [1, 2, 3]
[2,3,4]

Map a function over a NonEmpty stream.

O(n) map f xs is the ShortByteString obtained by applying f to each element of xs.

O(n) map f xs is the ShortByteString obtained by applying f to each element of xs.

Fold pairs into a map.

O(n) Modify every value in the queue.

O(n) Modify every value in the queue.

O(n) Modify every value in the queue.

Transform this map by applying a function to every value.

Transform this set by applying a function to every value. The resulting set may be smaller than the source.

>>> HashSet.map show (HashSet.fromList [1,2,3])
HashSet.fromList ["1","2","3"]

Map a function over a Stream

Type-level fmap for type-level functors. Note: this name clashes with Map from containers. FMap is provided as a synonym to avoid this.

Example

>>> data Example where Ex :: a -> Example  -- Hide the type of examples to avoid brittleness in different GHC versions

>>> data AddMul :: Nat -> Nat -> Exp Nat

>>> type instance Eval (AddMul x y) = (x TL.+ y) TL.* (x TL.+ y)

>>> :kind! Ex (Eval (Map (AddMul 2) '[0, 1, 2, 3, 4]) :: [Nat])
Ex (Eval (Map (AddMul 2) '[0, 1, 2, 3, 4]) :: [Nat]) :: Example
= Ex [4, 9, 16, 25, 36]

Hash-table, based on STM-specialized Hash Array Mapped Trie.

Invariant preserving version of Map from the containers packages, suitable for use with Uniplate. Use toMap to construct values, and fromMap to deconstruct values.

Monadic variant of mapAccumL.