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Comment by XorNot | Hacker News Reader

Ok so here's the problem I'm having with trying to get into Haskell, and it's a problem Carmack identified: there's way too many "toy examples" out there.

I've always learned languages because I need them for something. C/C++ because I wanted to write a game. Python because it's the complex scripting language of choice in Ubuntu. JavaScript for obvious reasons.

What I really really need is something which walks me through doing something significant with Haskell - like, a GUI app on Linux or something (my current focus: I've never really done it, but if I'm learning something new I'd like there to be a practical product at the end).

A bunch of language constructs, while technically interesting, don't help me to grok the language at all.

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Check out jekor's channel here he does walkthroughs of building full Haskell applications and deconstructing existing ones:

https://www.youtube.com/user/jekor/videos

Sounds good, but I really hate the video format (article or book would be better).

Ok, here's a book on doing Natural Language Processing with Haskell: http://nlpwp.org/book/index.xhtml

> there's way too many "toy examples" out there.

I am not sure what you mean. Tutorials can only deal with toy examples. Once you understand them, then you can (and you should) write bigger projects. About Carmack, that's exactly what he did, he implemented Wolf3D in Haskell to have a real impression about Haskell. (Assuming you're talking about this video where he discuss functional programming for games)

Aren't you just being lazy? :)

Edit: that video:

http://functionaltalks.org/2013/08/26/john-carmack-thoughts-...

I guess he's just as tired as I am of seeing (yet another) quicksort implementation in Haskell!

99% of the time I spend coding does not deal with data structures or algorithms, but basic business logic.

How does Haskell perform there? I don't know, but I know Haskell's quicksort oneliners are pretty (and pretty meaningless too).

I know my way around monads, I'm fluent in functional programming and grasped typeclasses... but I still can't see what's so great about Haskell beyond algorithmic beauty. I'd really like to be taught real-world-Haskell just like I was taught real-world-Lisp.

Well, I would argue that this article really is an introduction to functional programming using Haskell. Most of the concepts he/she introduce are not specific to Haskell but are more or less specific to functional programming languages.

But the author doesn't seem to be very well aware of that. Quoting the article: "Haskell is very different. The language uses a lot of concepts I had never heard about before."

All that to say that if you already know some functional programming this probably isn't for you.

Edit: clarity.

Exactly!

Don't get me wrong, I don't think that most Haskell tutorials are inherently bad, I just couldn't find a good introduction to Haskell targeted at programmers which are already familiar with functional programming concepts.

http://realworldhaskell.com

| Aren't you just being lazy? :)

I can't tell if this is a functional programming joke or not...

ahah, no. That was unintentional.

GUIs in haskell are currently a hot topic. Some of the older libraries like wxHaskell are a bit behind the times and need updating and the newer ones are very new and need vetting. If you're interested I'd check out threepenny-gui or learn opengl and use GLFW-b with the opengl bindings and write your own. #haskell and #haskell-game on irc.freenode.net are great hubs for gui related talk.

You'll really need to be able to use Monad and monad transfromers before you'll be able to use an idiomatic Haskell library, though.

There is "Write Yourself a Scheme in 48 Hours"[1].

[1]: http://en.wikibooks.org/wiki/Write_Yourself_a_Scheme_in_48_H...

Paul Hudak's "The Haskell School of Expression" (http://www.amazon.com/The-Haskell-School-Expression-Programm...), while it doesn't lead to a finished desktop application, does go deeply into its motivating example of building an animation library and a GUI for displaying and interacting with animations. (It also applies the techniques developed in the animation library to music.) It's not a "practical product" but it is "doing something significant," and much more than "a bunch of language constructs."

Not a tutorial but a video, but here's Anthony Cowley talking about using Haskell for machine vision, hardware, and robotics. In the first 5 minutes he writes Haskell code, proves it bug-free using a few tests via a Satisfiability Modulo Theorems prover, cross-compiles it to C, starts up a web server for debugging, then throws it on an Arduino.

Then he proceeds to run some basic vision filters in realtime using OpenGL, OpenCL, and OpenCV all together just to show off all in under 150 lines.

Then after that he talks about how his team built a robot doing realtime grasping and lifting of non-uniform, unpredictable, difficult to grasp, random dollar store objects that are coming at it on a conveyor belt moving at 33cm/sec. The visual processing all in Haskell from the noisy sensor of a Kinect.

The examples aren't immediately there to follow as it's not a tutorial, but it's a good look into the space of some real, complex hacking going on.

http://vimeo.com/77164337

Real World Haskell is the go-to resource for beginners http://book.realworldhaskell.org/read/ By well known Haskellers bos, dons, goerzen. Free online. Once LYAH whets your appetite exercises and real programs are needed.

http://book.realworldhaskell.org/

Spoiler alert: you can't really get anything signifant+useful done with that book, because Haskell is a language where only experts can get anything significant done.

If you just want the mindblow experience of Haskell: http://conway.rutgers.edu/~ccshan/wiki/blog/posts/WordNumber...

I have to strongly disagree on that point. I'm certainly not an expert (I hadn't done any meaningful programming in 10 years prior to reading it), and I found Real World Haskell immensely helpful in building a production system that receives and processes security events.

In fact, the chapter on building a Syslog server was incredibly useful, as the first piece of the system I'm building processes events which look a lot like Syslog (with some JSON embedded in the messages).

I will say that I had a hard time getting through the book as my only Haskell book. I ended up using Hutton's "Programming in Haskell" as a supplemental resource (selected mostly because it's a very small book).

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