Map (functional programming)

A map, in functional programming, is for making a change to each element of a list. A built-in variable, also known as a predicate (or "pred"), may represent ea

Map (functional programming)

A map, in functional programming, is for making a change to each element of a list. A built-in variable, also known as a predicate (or "pred"), may represent each element.

Depending on the language, the code can be arranged differently. map pred list; in Haskell[1] and Scheme.[2] map(pred, array); in Julia, Python,[3] PHP, and R. array.map(pred); in JavaScript, Kotlin, and V (Vlang).[4]

Examples

In the below, map is used to create a new array. 

square x = x * x -- function to square each element
>>> map square [1, 2, 3, 4, 5] -- apply to each element
[1, 4, 9, 16, 25] -- new array with changes

array := [1, 2, 3, 4, 5]
new_array := array.map(it * it) // apply to each element
[1, 4, 9, 16, 25] // new array with changes

References

  1. ↑ map in the Haskell Standard Prelude
  2. ↑ map in SRFI 1
  3. ↑ "Built-in Functions — Python 3.14.2 documentation". docs.python.org. Retrieved 2026-01-17.
  4. ↑ Rao, Navule Pavan Kumar (December 10, 2021). Getting Started with V Programming. ISBN 978-1839213434. OCLC 1290492862.


Content Disclaimer

Informasi ini disarikan dari Wikipedia dan disajikan kembali untuk tujuan edukasi. Konten tersedia di bawah lisensi CC BY-SA 3.0. Kami tidak bertanggung jawab atas ketidakakuratan data yang bersumber dari kontribusi publik tersebut.

  1. The information displayed on this website is sourced in part or in whole from Wikipedia and has been adapted for the purpose of restating it. We strive to provide accurate and relevant information, however:
  2. There is no guarantee of absolute accuracy. Wikipedia is an open, collaborative project that can be edited by anyone, so information is subject to change.
  3. It is not intended to constitute professional advice. The content displayed is for informational and educational purposes only. For important decisions (e.g., medical, legal, or financial), please consult a professional.
  4. Content copyright. Wikipedia is licensed under the Creative Commons Attribution-ShareAlike License (CC BY-SA). This means that content may be reused with appropriate attribution and shared under a similar license.
  5. Responsible use. Any risk arising from the use of information from this website is entirely the responsibility of the user.