Rather than commenting on the code provided, here are the two biggest wins I've had recently with Haskell. Both of these are part of a physical modeling project.
1) uu-parsinglib - simple to use and automatic error correction. I really, really enjoy working with this library, and how often can you say that?
2) STM - the original design reads a system and all inputs from a config file, then runs the system and produces output. I wanted to build the system from a file but collect inputs and produce output in real-time. After a few small adjustments, a few TVar's and a TMVar, and three forkIO's, it was working.
One concern is that the engine (which is computation-intensive) shouldn't block waiting for input, it should just continue on and catch up later. With STM, this can be expressed as:
atomically $ getInputs inputTVar `orElse` return ()
and there's the desired behavior. Couldn't be easier.
John
From: Blake Rain <blake.rain@gmail.com>
Dear Haskellers,
I thought I'd take some time to share something of my weekend with
you all. Not because of anything new, but because it is a
feel-good example of Haskell being win. A good read for Monday
morning, perhaps.
<code snipped>
Now over to you guys! What experiences have you had which make you
glad you use Haskell? Anything make you smile recently?
- Blake