The other day I visited haskell.org, and was astonished to discover that 
there are now some news items dated this year. :-P



The item in question refers to a company I've never heard of - FP 
Complete. Naturally, I went over there and had a nose around. Reading 
their blog was... interesting. Consider this entry, for example:

https://www.fpcomplete.com/blog/2012/03/onamission

Or how about this:

http://tinyurl.com/cwn8eq4

Now, to be clear, I am a Haskell enthusiast. I think Haskell is 
brilliant, and that everybody should be using it. But reading that first 
post, even to me it sounds like... every over-hyped product I've ever 
read about. It talks about how "Developers who use Haskell often report 
2x  or higher productivity improvements, even as their bug count is 
significantly reduced.", but without a single shred of substance. You 
could take the word "Haskell" and replace it with any other programming 
language on Earth, and the sentence would be equally vacuous.

It reads like one of those pamphlets that Dell were so fond of sending 
me. You know the ones, where they tell you how Dell products "reduce 
total cost of ownership" and how Dell provide "end-to-end solutions", 
but without one single shred of technical detail. In other words, the 
kind of crap written for the Pointy Haired Boss, not for me!

Likewise, some of these blog posts sound almost hysterical in their over 
optimism. Don't get me wrong, I think Haskell is fantastic. But I've 
long since given up hope of anybody ever actually using it. (And even if 
somebody did use it, nobody will ever take it seriously in public.)



One *real* contribution which is interesting is a framework for running 
Haskell on their website. There's already a site that does this:

http://tryhaskell.org/

It even has a little Haskell tutorial built into it. (Last time I 
checked, it's fairly incomplete.) So how does this new offering compare?

Well, tryhaskell.org gives you a Haskell REPL. This new site appears to 
be some kind of Wiki where you can embed Haskell fragments, with a 
button to execute them. This means that rather than entering single 
expressions, you end type in a lengthy chunk of code and then execute 
it, with is a feature. On the other hand, the time required to compile 
the code and display the result seems quite length, with is a drawback.

(There's been an IRC bot which provides a sort-of Haskell REPL for 
years. But it's only fairly recently that tryhaskell.org appeared, to 
allow casual users to experiment with Haskell without needing to install 
an IRC client and join a special IRC server - or worse, attempt to 
compile the IRC bot themselves! It's bit-rotted like crazy over the 
years...)

Making a website where you can run Haskell interactively *sounds* like 
such a simple task... When you sit down to try and actually *do* it, you 
suddenly realise that all sorts of petty practical concerns make this 
way harder than you'd imagine. For example, a simple typo can an 
infinite loop; you don't want to hang the entire web server if a user 
makes a mistake! And hey, what about security? We don't want some user 
to issue a Haskell command to format the harddrive. Then there's the 
mechanics of turning a lone Haskell expression into a full module which 
can be compiled... It's all a lot more fiddly than you'd think.

It's nice to see a few people managing to do this now. In fact, I've 
often thought it's a bit of a pity we don't have a small Haskell 
interpreter written in Haskell, so it could be embedded into other 
things. (We *have* an interpreter, but it is *not* small or simple!)

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