On Tue, 4 May 2004, Bill Walsh wrote:
I am amazed that you can even think of doing anything in a week. I have been at it for at least 15 years: one project; one dead set proof-of-concept .
Well I'm sure you're doing something much more useful/worthwhile than I! =) I understand that the example program I initially thought of is rather, well...typically imperative. That's sort of the reason I chose it. Not only does it have real-world ramifications to my customer (the problem domain is similar) but it will hopefully show me the worst of the best. I.e., Haskell is a beautiful language [disclaimer: this comes from me not really being a Haskell programmer, but admiring it from afar if you will] and can express some unbelievably advanced concepts elegantly, but is it really nasty doing "normal" software crap like loading a bunch of data, popping up GUI windows, etc. etc.? I was hoping that I can piece together something fairly quickly within two weeks in those three languages. They don't have to be robust, or even beautiful. In fact, I can guarantee they won't be. But the real point of the exercise is for me to figure out which environment is the easiest for me to get along with.
I will follow your progress with intense interest. Your are obviously an experienced programmer, but it is your analytical skills which interest me most.
Well, I am an experienced programmer, but certainly not in the same class as most lambda-junkies as yourselves. I have a long sordid history of programming in imperative languages and I've been bitching about switching for long enough that it's time to put my money where my mouth is, so to speak. I've dabbled in Scheme and Erlang and ML. To be frank, I've all but discarded Erlang as a viable language. Don't get me wrong...it's got some great features; I just think that I could easily implement Erlang in Scheme or Haskell and be quite happy. (At some point in the future when I'm smarter =) So to me, the real question is: Haskell, the pure, or Scheme, the dirty? Haskell is lazy all the time. That's awfully nice...I'm not sure if there's a performance penalty somewhere, but assuming there isn't, kudos to it. Scheme lets you be selectively lazy with macros. At least it's highly customizable (for instance, pattern matching can be implemented in Scheme with macros, whereas other languages that have fixed special forms are quite limited). But Scheme lets you change things if you want to! (The Haskell afficianados gasp). Let's face it...in most long-running applications, data changes a lot during the lifetime of a program. So somehow, you have to manage the repercussions of state changes. Haskell does this with monads. (I'm still wrapping my brain around them, but...) Apparently monads plus some syntactic sugar are like functions that return a value and the next function, which in turn returns a value and the next function, etc. so that referential transparency is maintained. This is a heckuva lot of work to do (set! foo 'bar). I hope I'm not far off base with this. I guess it boils down to this: Haskell ensures that your bindings are never ever ever corrupted, and thus the sematic value of your program is never compromised from the outside. The cost of this is a sharp learning curve, and quite possibly a performance hit. Scheme lets you tromp all over stuff (well, you get the picture), in effect letting you still have control over when you really need to do something imperative for performance or simplicity reasons. I'm not sure which I *like* better. So far neither is visually appealing, mostly because I'm not familiar with them. Scheme seems to have a slightly bigger population than Haskell, which of course means squat because if I really cared about how many programmers of language X there are out there I'd just code in Java (which, sadly, I'm doing now). Anyway, I'm starting to ramble, but I talked to a friend who has similar feelings but is actually pretty good at Common Lisp. He suggested I refocus my energies, and I agree: instead of biting off more than I can chew, and having to learn a whole wad of APIs that aren't really about the language (read: wxHaskell or gtk2hs/the like, or audio packages etc.), just code some really simple problems. Like the Sieve of Eratosthenes, in all three languages. Or a simple publish/subscribe framework with a "master" state holder and many slaves. Or quicksort. Etc. etc. So I'm going to head down that path right now, and try to get a feel for the languages in a slightly more pure fashion. I'll still try to get performance metrics out of them, but I'm not going to bang my head against the wall learning new languages, GUI toolkits, and FFIs all in two weeks. =) Thanks for the replies so far, I really appreciate them. -- Mike J. Bell This is all just my opinion. "Outside of a dog, a book is man's best friend. Inside it's too dark to read." mikeb@manor.org