HN Explorer

Ask HN: How can I learn Haskell?

15 points by jxm262 ↗ HN
I've had enough people mention the benefits of learning Haskell that I've decided to take the plunge. I'm very interested now in Functional Programming and want to "level up". I've taken the Intro to FP and Reactive Programming class on Coursera and loved it, but also know I have alot more to learn.

There's a ton of info online about this question that I'm feeling a bit overwhelmed.

Any tips or good resources that the community can recommend?

6 comments

[ 3.1 ms ] story [ 14.9 ms ] thread
codygman
Use Stack instead of installing Haskell platform, your distro's Haskell package:

https://github.com/commercialhaskell/stack

After installing stack and putting ~/.local/bin on your path here is how I start a project:

    cabal init
    < answer questions >
    stack init
The above will be replaced by `stack new` in the future I think, but `stack new` doesn't work for what I'm doing atm.

Learning:

https://github.com/bitemyapp/learnhaskell

http://haskellbook.com/

After those, just start writing crappy Haskell code to solve real tasks you need/want solved. The most important thing is to focus on creating working software with the language, since that's the fastest way to learn.

After you've done this a couple times start reading source code of libraries which solve the same problems you've implemented and see how they are different. This may include lots of learning before you understand the libraries.

Once you understand this library, start going down the most popular libraries and understanding how they work (You might want to skip lens though! I hear it's very difficult to understand the source code and sheer generality):

http://hackage.haskell.org/packages/top

Some papers I feel I'd do a disservice of not mentioning:

http://homepages.inf.ed.ac.uk/wadler/papers/marktoberdorf/ba...

http://www.cs.virginia.edu/~wh5a/personal/Transformers.pdf

Also, I use these as references while writing crappy (and sometimes not as I get more experienced) Haskell code:

https://en.wikibooks.org/wiki/Haskell

http://book.realworldhaskell.org/read/

http://book.realworldhaskell.org/read/

http://adit.io/posts/2013-04-17-functors,_applicatives,_and_...

https://www.fpcomplete.com/school

https://www.fpcomplete.com/recent-content

pdiddy
I haven't worked through it but the approach to Learn You a Haskell seems fun:

http://learnyouahaskell.com/

sfilipov
I am also currently learning Haskell and went with LYAH. I think it is a good enough textbook to introduce the theoretical part while giving enough examples.

My problem was that I was able to understand the concepts but couldn't write functions that do what I want them to do. To gain some experience I am working through 99 Haskell [1] and HackerRank FP domain [2]. Quite a lot of exercises there.

[1] http://www.99haskell.org/ [2] https://www.hackerrank.com/domains/fp/intro