Skip to Content
Programming Elm
book

Programming Elm

by Jeremy Fairbank
July 2019
Intermediate to advanced
310 pages
7h 26m
English
Pragmatic Bookshelf
Content preview from Programming Elm

Test-Driven Development in Elm

You learned in Chapter 7, ​Develop, Debug, and Deploy with Powerful Tooling​ that the use of static types won’t prevent all bugs. Recall the Picshare bug that added new photos to the end of the feed instead of the beginning.

​ feed ++ model.streamQueue

Elm’s type system doesn’t notice the bug because feed and model.streamQueue have the same type. A test could have prevented this bug.

Testing also helps you to better design your code modules’ APIs. Developers call this test-driven development (TDD), or test-driven design. Some developers claim that test-driven development and design are different while others say they’re the same. We won’t wade into that debate; it’s almost as bad as whether or not you should use ...

Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.

Read now

Unlock full access

More than 5,000 organizations count on O’Reilly

AirBnbBlueOriginElectronic ArtsHomeDepotNasdaqRakutenTata Consultancy Services

QuotationMarkO’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.
Julian F.
Head of Cybersecurity
QuotationMarkI wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.
Addison B.
Field Engineer
QuotationMarkI’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.
Amir M.
Data Platform Tech Lead
QuotationMarkI'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Mark W.
Embedded Software Engineer

You might also like

Elm in Action

Elm in Action

Richard Feldman
Programming Ecto

Programming Ecto

Darin Wilson, Eric Meadows-Jonsson

Publisher Resources

ISBN: 9781680507164Errata Page