Functional Programming For Dummies by John Paul Mueller

Author:John Paul Mueller
Language: eng
Format: epub
ISBN: 9781119527510
Publisher: Wiley
Published: 2019-04-02T00:00:00+00:00

Sorting data with Haskell

Haskell provides a wide variety of sorting mechanisms, such that you probably won’t have to resort to doing anything of a custom nature unless your data is unique and your requirements are unusual. However, getting the native functionality that's found in existing libraries can prove a little daunting at times unless you think the process through first. To start, you need a list that’s a little more complex than others used in this chapter: original = [(1, "Hello"), (4, "Yellow"), (5, "Goodbye"), (2, "Yes"), (3, "No")]. Use the following code to perform a basic sort:

import Data.List as Dl

sort original

The output is based on the first member of each tuple: [(1,"Hello"),(2,"Yes"),(3,"No"),(4,"Yellow"),(5,"Goodbye")]. If you want to perform a reverse sort, you can use the following call instead:

(reverse . sort) original

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.