Functional Programming in Typescript
$7.99
Minimum price
$9.99
Suggested price

Functional Programming in Typescript

A Practical Guide

About the Book

Learn how to write programs the functional way with Typescript and the fp-ts library! This book was written for people who are less or not at all familiar with functional programming. It explains basic functional techniques (including monads) and demonstrates their use in practical examples and projects. In those projects you deploy to the AWS cloud, work with a REST API and store information in a database.

  • Share this book

  • Categories

    • Node.js
    • TypeScript
    • Amazon Web Services
    • Functional Programming
  • Feedback

    Email the Author(s)

About the Author

Sam Van Overmeire
Sam Van Overmeire

Professional programmer, focussed on building applications in the Cloud.

About the Contributors

Andrea Simone Costa
Andrea Simone Costa
Francis Godawski
Francis Godawski
Park Junseung
Park Junseung

Table of Contents

  • Acknowledgments
    • About the book cover
  • Introduction
    • Caveat Lector
    • Why FP?
    • Why Javascript?
    • Why Typescript?
    • Why FP-TS?
    • Motivation for this book
    • What you should know
    • Overview
  • Tidbits: Some Useful Javascript and Typescript
    • Requirements
    • Setting up a new project
    • More than one way to build a function
    • Backticks for easy printing
    • The ternary operator
    • Discriminating unions
    • Summary
  • First Steps with Functional Programming
    • What is Functional Programming
    • Pure functions, referential transparency and immutability
    • Writing functional code
    • Writing functional programs
    • Monads
    • Briefly about types again
    • Summary
  • Our First Project: User Registration
    • Defining our types
    • Validation with Either
    • Before we continue: Either or Validation?
    • Creating our user with lifting
    • Bringing it together
    • Change is inevitable - how to cope with it
    • Summary
  • Deploying a monitoring application
    • AWS Lambda and SAM
    • Setting up our project
    • Using the Cloudwatch SDK
    • Monads for asynchronous behavior
    • Transforming our data
    • Synchronous behavior and IO
    • Bringing it all together
    • Extensions
    • A small aside: memoization
    • Key points
    • Summary
  • Testing
    • The types of testing
    • You mentioned TDD?
    • FP and testing
    • Property-based testing
    • Other tools for better code
    • Summary
  • Once more unto the breach: our final application
    • Setting up
    • Writing our first Create Lambda code
    • Core logic of the Create Lambda
    • Bringing it together
    • Creating the Retrieve Lambda
    • DynamoDB
    • Adding the real database
    • Summary
  • Expanding our reservation application
    • Using the Reader Monad for gathering config
    • Using State
    • Better error types
    • Restaurants and sequenceS
    • Choosing configs
    • Exploring some more ideas
    • Summary
  • Rewriting an application
    • The original application
    • Evaluation
    • Improvements overview
    • Our new code setup
    • Validation
    • Dealing with the asynchronous calls
    • Advantages of our functional approach
    • Summary
  • Advanced FP techniques
    • Domain Specific Languages
    • Tagless final
    • Free monads
    • Executable and declarative encoding, algebraic design
    • Summary
  • Conclusion
    • What we learned
    • Where to go from here
  • Appendix A: Additional Concepts
    • Writer
    • These
  • Notes

The Leanpub 60 Day 100% Happiness Guarantee

Within 60 days of purchase you can get a 100% refund on any Leanpub purchase, in two clicks.

Now, this is technically risky for us, since you'll have the book or course files either way. But we're so confident in our products and services, and in our authors and readers, that we're happy to offer a full money back guarantee for everything we sell.

You can only find out how good something is by trying it, and because of our 100% money back guarantee there's literally no risk to do so!

So, there's no reason not to click the Add to Cart button, is there?

See full terms...

80% Royalties. Earn $16 on a $20 book.

We pay 80% royalties. That's not a typo: you earn $16 on a $20 sale. If we sell 5000 non-refunded copies of your book or course for $20, you'll earn $80,000.

(Yes, some authors have already earned much more than that on Leanpub.)

In fact, authors have earnedover $13 millionwriting, publishing and selling on Leanpub.

Learn more about writing on Leanpub

Free Updates. DRM Free.

If you buy a Leanpub book, you get free updates for as long as the author updates the book! Many authors use Leanpub to publish their books in-progress, while they are writing them. All readers get free updates, regardless of when they bought the book or how much they paid (including free).

Most Leanpub books are available in PDF (for computers) and EPUB (for phones, tablets and Kindle). The formats that a book includes are shown at the top right corner of this page.

Finally, Leanpub books don't have any DRM copy-protection nonsense, so you can easily read them on any supported device.

Learn more about Leanpub's ebook formats and where to read them

Write and Publish on Leanpub

You can use Leanpub to easily write, publish and sell in-progress and completed ebooks and online courses!

Leanpub is a powerful platform for serious authors, combining a simple, elegant writing and publishing workflow with a store focused on selling in-progress ebooks.

Leanpub is a magical typewriter for authors: just write in plain text, and to publish your ebook, just click a button. (Or, if you are producing your ebook your own way, you can even upload your own PDF and/or EPUB files and then publish with one click!) It really is that easy.

Learn more about writing on Leanpub