Which functional programming language should I use?

Question

NOTE : i don't agree btw this is a double question. Please read carefully. I want to know more than just production/studying. Maybe I should lay another accent then and rephrase it? One of my questions is :

• for GUI
• for diff. OS ? Windows?
• for anything you can come up with: a general positioning of functional languages thus.

I know this is probably a subjective question, still, I'm sure there's a lot that could be said. I'm learning Haskell this moment, and, have to admit, I'm struck by its sheer beauty.

Still, Haskell is only one language, and I have no clue how one functional language differs from te next one. I've came across lots of imperative languages (OO or not) in my life, and I think, as much as the next guy, the imperative languages, COBOL and C# are hardly comparable. If there's that much difference in functional languages, is the choosing of one very relevant to me.

Of course, which language to use is very dependant of the context, I can imagine that the answer on 'Which functional language to use for production code' (any?) as not the same as 'Which language to use to study the functional language principles', so I very much would like some positioning of the different languages. Like which should I use when I need a GUI? Which one have compilers for windows to? Is Haskell 'the' functional language, and so forth...

Answer 1

Haskell is definitelly one of the choices. You can also try at clojure. It's a lisp, functional, has access to a large amount of java libraries, cross platform, can use swing or swt or qt for gui, ...

Answer 2

I think this may be a duplicate of e.g.

http://stackoverflow.com/questions/171719/functional-languages-when-to-use

http://stackoverflow.com/questions/102911/whats-a-good-functional-language-to-learn

Answer 3

I would recommend learning F# since it is not only functional, but it also takes advantage of the richness of the .NET framework to allow to use objects where it is applicable.

Scala and Clojure are other functional languages that can also use Objects where applicable.

Answer 4

Take a look at F#. Full support within the next release of Visual Studio and of course you get access to the .NET framework.

Answer 5

Standard ML and LISP/Scheme are two obvious candidates.

ML is a remarkably clean and well-designed language, very nice to work with, and it differs from Haskell in two main ways: It doesn't have lazy evaluation, and it allows side effects in some cases. F# is pretty much a .NET port of ML.

At my university, first-year students are taught it as an intro to programming.

Lisp or one of its variants like Scheme are always an eye-opener too, although more for its powerful (lack of) syntax than for being functional.

Both are definitely worth exploring if you want to see what diversity exists within the field of functional languages.

For practical use, F# is probably your best bet, given how well it integrates with the .NET class library, which gives it a lot of functionality for free.

Answer 6

There are a few different axes here you're considering, so here's some scaffolding I hope others may fill out:

Statically-typed (ST) vs. Dynamically-typed (DT)?

Pure (PURE) vs. side-effects (MUT)

Platform/runtime: .Net (NET) vs. JVM (JVM) vs. other?

Intended more for academic (ACAD) or production (PROD)? (This is quite subjective, many "academic" languages have seen commercial and production use, and vice versa)

---

(please fill in the blanks!)

Language         type      platform    use      gui framework/ lib
----------------------------------------------------------------
Haskell          ST,PURE   other       ACAD     see (*)
Clojure          DT,MUT    JVM         PROD     Swing
SML              ST,MUT    other       ACAD
OCaml            ST,MUT    other       PROD     Tk and GTK
Scala            ST,MUT    JVM         PROD     Swing
F#               ST,MUT    NET         PROD     wpf, winforms
Common Lisp      DT,MUT    other       PROD
Erlang           DT,MUT    other       PROD
<add others>

(*) http://www.haskell.org/haskellwiki/Applications_and_libraries/GUI_libraries

Answer 7

Haskell will certainly teach you functional programming, and it is cross platform, has GUIs, is used commercially, and gives you good options for multicore programming. It wouldn't be the wrong choice.

It depends on what exactly you're seeking to learn.

Answer 8

I'd agree with those suggesting you take a look at F# It allows you to mix OOP and functional programming style in a (almost - downcasts to interface, I'm talking to you!) seamless fashion, is pretty fast, includes full interoperability with .NET, is statically typed (compile-time type resolution is great and will save you some headaches associated with dynamic languages...besides you get intellisense!) and last but not least it's becoming supported out of the box in VS2010. The beauty of F# is that it doesn't force you down a path, but lets you do efficiently and elegantly what you want, the way you want to do it.

Answer 9

I'll just plug Erlang as a DT/MUT/Other/PROD language since no one else has.