Learn Functional Programming

This is a collection of exercises to accompany a half-day workshop on the basics of functional programming.

NOTE: This is not a way to learn hardcore, mathematically correct “functional programming”. This is a collection of exercises to help teach common functional programming techniques that will make your code easier to debug and maintain, regardless of whether or not you have any idea what the fuck a monad is.

Quickstart

# Clone the exercises
git clone https://github.com/jlengstorf/learn-fp-exercises.git

# Move into the exercise directory
cd learn-fp-exercises/

# Open the first exercise
open exercises/01-map-array.html

In your favorite code editor, open the JavaScript for the exercise (src/01-map-array.js), read the instructions, and refactor away!

If you get stuck, the refactored code is available in src/solutions/. This isn’t a test, so don’t feel guilty if you need to see a solution to finish a given exercise. However, please actually write the code for each solution by hand — typing things out helps them stick.

Using Chrome Developer Tools

If you'd like to use Chrome’s Developer Tools to do the exercises, follow these steps:

1. Open the Developer Tools: command + option + I or, in the menu, View > Developer > Devleoper Tools

2. Click the "Sources" tab.

3. control + click in the file panel at the left and choose "Add folder to workspace"

4. DevTools will request full access to the folder. Click "Allow"

5. control + click the file 01-map-array.html and choose "Map to File System Resource..."

   

6. Choose 01-map-array.html from the dropdown.

Now you can modify and save changes right from DevTools — no editor required!