map -package:basement -package:containers -package:ghc

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, ...]

this means that map id == id

Examples

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

>>> map id [1, 2, 3]
[1,2,3]

>>> map (\n -> 3 * n + 1) [1, 2, 3]
[4,7,10]

Apply a function to each element, returning any other valid ListLike. rigidMap will always be at least as fast, if not faster, than this function and is recommended if it will work for your purposes. See also mapM.

Apply a function uniformly over all elements of a sequence.

Map a function over all values in the map.

Map a function over a NonEmpty stream.

O(n*log n) Map a function over all the left keys in the map. Version 0.3

Combinator for the <map> element. Example:

map $ span $ toHtml "foo"

Result:

<map><span>foo</span></map>

Map over bytes in a sequence. The result has the same length as the argument.

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

O(n) map f xs is the ByteString 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.

Transform the original string-like value but keep it case insensitive.

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

map f (x1 :> x2 :>  ... :> xn :> Nil) == (f x1 :> f x2 :> ... :> f xn :> Nil)

and corresponds to the following circuit layout:

Apply a transformation to all values in a stream. Subject to fusion

Apply a transformation to all values in a stream. Subject to fusion Since 0.3.0

Map over the elements of an array. Note that because a new array must be created, the resulting array type can be different than the original.

Map a function over all values in the map.

Apply function to every element of matrix

Decode a Map from a toMap expression or generally a Prelude.Map.Type.

>>> input (Dhall.map strictText bool) "toMap { a = True, b = False }"
fromList [("a",True),("b",False)]

>>> input (Dhall.map strictText bool) "[ { mapKey = \"foo\", mapValue = True } ]"
fromList [("foo",True)]

If there are duplicate mapKeys, later mapValues take precedence:

>>> let expr = "[ { mapKey = 1, mapValue = True }, { mapKey = 1, mapValue = False } ]"

>>> input (Dhall.map natural bool) expr
fromList [(1,False)]

map f xs is the DList obtained by applying f to each element of xs. <math>(length (toList xs)). map obeys the law:

toList (map f xs) = map f (toList xs)