Re: [Haskell-cafe] Elevator pitch for functional programming

At Tue, 20 Jan 2009 14:17:10 -0800, Ryan Ingram wrote:

I recommend checking out Don Syme's slides from CUFP 2008.

http://cufp.galois.com/2008/slides/

This isn't Haskell directly, it's F#, but it fits the "functional programming generally", and the two languages have, relative to the universe of programming languages, more in common than they do different.

There's a lot of "would you rather write this?" with a giant chunk of C#, followed by "or this?" with a few readable lines of F#.

Hi, those slides look useful and inspiring. Thanks a lot. Jim

-- ryan

On Tue, Jan 20, 2009 at 2:07 AM, Jim Burton wrote:

...

Hi, I will be a TA on a comparative PL course and I'm looking for small examples (ammunition) which motivate the use of Haskell and functional programming generally. The course is for 1st year Software Engineers, none of whom are likely to have used a functional language. They will all have experience programming Java and a little C++, with a few of them knowing Python, Ruby, PHP etc etc too.

If anyone has code snippets which are the equivalent of an elevator pitch for FP, I would be very grateful to see them. What I want are some small concrete examples of idioms which are natural and powerful in Haskell but difficult or impossible in, say, Java.

So I can produce examples of some of the things that make FP powerful, elegant, expressive etc: higher order functions, polymorphism, composition (ask them to write (.) in Java :-)), partial application and so on. I will point any interested souls to Hughes' great paper [1]. But I have little time and it might be hard to put across why they would want to do these things in the first place. I was looking for something that speaks directly to the kind of problems they face in languages like Java...

Types are a good example because Java programmers generally already appreciate the help they get from compiler messages etc, so you can sell a more flexible, enhanced form of this. Purity might appeal to anyone who has longed to be able to reason about nastily complex code with a lot of shared state. Laziness, streams? Hard to do in Java (I presume) but also quite hard to sell the need.

The existence of an O'Reilly book will help, especially one that can be sampled online, so I'll point them at RWH for extended concrete examples. They will need to be already sold before they will bother with that though.

Thanks,

Jim

[1] http://www.cs.chalmers.se/~rjmh/Papers/whyfp.html _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe