Ask HN: which functional language to learn?

https://news.ycombinator.com/item?id=689808

by vijayr • 17 years ago

30 47 17 years ago

news.ycombinator.com

I'm looking at learning a functional programming language, but not able to decide which one. The language should be fun to learn and also have decent job opportunities.

Based on some initial reading, Haskell and Erlang seem to be good choices. Can anyone suggest a language?

My background (not sure if it matters) I've worked with Java/PHP/Ruby, developing desktop and web applications.

michael_dorfman• 17 years ago

I'd suggest Scheme, just because the SICP videos make learning it easy and fun (http://groups.csail.mit.edu/mac/classes/6.001/abelson-sussma...). And, once you get the functional concepts, Haskell and/or Erlang should be relatively easy.

_giu2• 17 years ago

I think this is a good idea to first learn the basic functional concepts using Scheme and the SICP videos (heard a lot of good things about the videos and the book). I'm learning Haskell (I'm a C# guy) and some things are a bit difficult to understand if you have an object oriented background. I think I'll have a look at the SICP videos, too

vijayr3• 17 years ago

Did you learn Scheme and then moved to Haskell, or directly started with Haskell?

vijayr3• 17 years ago

I did find lot of books/resources for Haskell and Erlang too.

If it were the usual programming languages (PHP, Ruby, Python etc), making a choice is relatively easy. For functional languages, I'm not sure where to even begin.

troels4• 17 years ago

> If it were the usual programming languages (PHP, Ruby, Python etc), making a choice is relatively easy.

What do you mean by that? Is it just that you know this field better and thus feel better informed, or are you hinting at something else, that I didn't get?

Xichekolas• 17 years ago

I'd definitely second SICP if you've never done functional before. It teaches you functional concepts almost without you even realizing it.

OTOH, if you are really interested in being truly pure, it's hard to beat Haskell. Real World Haskell is a great intro for that language, and it's free online.

troels4• 17 years ago

Ruby, used that way, is quite a functional language. I think you might find a lot of similarities to Scheme, which might make it easier to get in to. I know I did (although reversed .. I learned Scheme first).

apgwoz• 17 years ago

I think this comes up enough that we should have some sort of FAHN: Frequently Ask(ed) Hacker News.

That said. Scheme with SICP, or The Little Schemer and then SICP

sdevlin2• 17 years ago

I've got to second The Little Schemer. I ran through it earlier this year, and it was the most fun I've had programming in a long time.

mvalente• 17 years ago

Javascript

noblethrasher4• 17 years ago

Seconded. Although it's a functional language in the same way lisp is (i.e. it isn't).

cema7• 17 years ago

Javascript is a great language (and widely misused, alas). However, calling it a functional language is a very big stretch (unlike lisp).

troels4• 17 years ago

Javascript has a lot of Scheme legacy. I'd definitely call it a functional language.

Stasyan3• 17 years ago

I learned OCaml first, and then switched to F#. Out of all languages I know (OCaml, Java, C#, C++, Python, VB, Lisp) - IMHO F# is the best one. Learning curve is pretty steep though, once you move past the basics.

zikzikzik• 17 years ago

> Learning curve is pretty steep though

Do you mean it gets difficult, or that progress gets fast?

Stasyan3• 17 years ago

It gets difficult. F# has pretty much everything from every other functional language. Even though F# is very consistent language. There are a lots of concepts to understand.

peregrine• 17 years ago

Could also be the very new state of it with lack of good documentation.

cema7• 17 years ago

Clojure. It's a lisp on JVM.

babo• 17 years ago

What about clojure? With a Java background it's easier to grasp, has all the modern features and a friendly, supportive community. It's load of fun, you could even use SICP with it. For job opportunities you need a good load of luck with any functional language. With such a close integration with Java you have a high chance for a stealth clojure project. :-)

xtho• 17 years ago

In consideration of your background, scala would come to mind. There is some dispute about whether it's a functional language, though.

johnbender• 17 years ago

Haskell is a bit into the weeds if you're just starting out. I jumped in with Erlang, as its pretty pragmatic so the tutorials out there tend to focus on getting crap done and not so much theory.

Once you've written some code and feel comfortable with FP, then drink the Haskell-aid.

rosejn• 17 years ago

Clojure. Without a doubt. It's by far the easiest and most productive Lisp around right now. You get a modern core library with great support for concurrency, and you can use Java libraries with ease. The new Clojure book published by the Pragmatic Programmer guys a pretty good read, and it gets into the important aspects of functional and concurrent programming. I've been having a blast so far.

c00p3r• 17 years ago

How big should be the server to run this site (with all its traffic), if it could be ported from ark to Clojure? =)

wilkes• 17 years ago

Haskell:

http://learnyouahaskell.com/

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

johngunderman• 17 years ago

I would also suggest http://en.wikibooks.org/wiki/Write_Yourself_a_Scheme_in_48_H... as it not only teaches Haskell, but also Scheme (as the tutorial covers the construction of a Scheme interpreter)

caffeine2• 17 years ago

Notes about Haskell:

It's strange, but Haskell is more difficult to read than write. This is because most code on e.g. Hackage uses some very complicated gymnastics involving Applicative, Arrows, or whatever. So it's hard to learn from other people's programs.

Also, a warning: learning Haskell might screw with your ability to write code in other languages! It took me two weeks before I stopped making every line of Python a lambda.

baguasquirrel• 17 years ago

I'm really curious to see how other people are progressing through the learning process for Haskell (and other HM-based functional languages). I rarely use lambdas, and I feel that Haskell is much easier to read than to write. Clearly there's something different about our approaches. I learned SML back in school, picked up OCaml about 3 years ago, and picking up Haskell was still a bit of a trip.

miloshh• 17 years ago

Definitely Haskell. May I add one more resource for learning it that worked great for me, the official "Gentle Introduction to Haskell":

http://www.haskell.org/tutorial/

For those already proficient with programming that just wnat to pick up Haskell, it's ideal.

Then I would suggest an exercise that involves manipulating abstract syntax, for example parsing and interpreting a little language. ("Build yourself a Scheme..." might be good though I didn't read it myself.) This is where the language really shines, and you don't need any of the recently popular trickery like arrows or GADTs.

marcocampos2• 17 years ago

In my opinion don't learn any LISP, Common LISP or Scheme, it doesn't matter. Why? Fragmentation. It's very hard to write something a bit complex that can run on the various LISP compilers/interpreters without heavy changes. Also, there is a lack of good and up-to-date 3rd party libraries/frameworks which leads to having to write things that most languages already provide by default or than can be easily obtained.

Go with Scala, Clojure or Haskell. The first two run over the JVM and seem to have a very nice community behind them. Haskell is very cool and it will definitely change the way you look at programming.

There is also F# which is very cool and runs over the .NET framework. If you're into Microsoft stuff then it might be worth it.

cema7• 17 years ago

Well, technically Clojure is a lisp, but it does indeed depart from the heavyweight lisp legacy as represented by Common Lisp. And portability is much easier when all your libraries are in JVM. :-)

Scala started earlier than Clojure and has a bigger community around it. Clojure is clean and grows quickly, it has a very good potential. Besides, it has a strong and multifaceted support for parallel (multicore) programming. Both Scala and Clojure run on top of JVM and interop with it.

Haskell has had a strong following in academia for quite a while now. Newer languages borrow from it.

I have not tried F# which, as far as I understand, is a kind of ML on .NET. Its community seems to be smaller, but it may be due to the usual animosity some people feel regarding anything that comes out of Microsoft. Reportedly the language is well designed.

marcocampos2• 17 years ago

Maybe F# acceptance will grow when Visual Studio 2010 comes out, since it will be one of three new native languages: IronPython, IronRuby and F#.

unignorant• 17 years ago

I recently asked myself the same question, and I ended up settling on SBCL (Common Lisp).

Emacs coupled with SLIME provides the best development environment I have yet experienced. For me, the greatest downside is that the code I end up with is often quite system-specific.

cema7• 17 years ago

I too settled on SBCL for a while, but then looked around a bit wider. Clojure is an intriguing development. I recommend that you look at it, both the language and the community. It has a good promise, borrowing the best from the older lisps and leaving behind the unnecessary legacy.

So, unless you need to support or interact with past Lisp code, I think Clojure may be a better tool for most of us. YMMV, as usual.

noblethrasher4• 17 years ago

As I'm sure you know, functional programming is a style and you can use it for any of the languages you mentioned (yes, including Java - objects are a poor man's closure but closure's are a poor man's object) [1]. One thing that might help is to try using functional idioms in the languages you know. Then you'll appreciate the syntatic help that "real" functional provide for that style.

[1]http://people.csail.mit.edu/gregs/ll1-discuss-archive-html/m...

troels4• 17 years ago

One more thing that you may or may not know is that functional programming languages are a kind of fuzzy concept. There are at least two different categories (well, probably it's more a continuum, but ..), being functional programming languages vs. function-level programming languages. (Note: Someone please correct me, if I'm confusing the terms here). Lisp's belongs in the first category, where Haskell probably belongs in the latter. The first category is more similar to main stream, procedural languages, where the latter is more abstract. Which is a better choice is open for debate; On the one hand, you'll probably grasp Lisp faster than Haskell, on the other hand you might end up writing procedural code in it, instead of function oriented code.

See: http://en.wikipedia.org/wiki/Function-level_programming#Cont...

Tangurena• 17 years ago

I work for a "microsoft shop." This means that if there is an MS and a non-MS choice of technology, we'll always take the MS one. Consequently, F# is the only possible choice for a functional language at work.

cema7• 17 years ago

I too work for a Microsoft shop. Installed Emacs, perl, MinGW/MSys with bash, cygwin (do not use it, though), python (do not use it), etc. JVM is already installed on all computers except the production servers. So the work that is of a "personal" scope (editing a file, analyzing a log, etc) I can use any technology which is available to me.

Of course, when we are talking about a group effort, we need a technology that everyone in the group is understanding. It is more difficult to convince others (including management) in a Microsoft shop to use non-Microsoft technologies. But it is possible.

Ask HN: which functional language to learn?

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