On 2012-12-08 07:16AM, Tomasz Rola wrote: >> On Fri, Dec 7, 2012 at 5:20 AM, Josh Grams <[email protected]> wrote: >>> On 2012-12-07 08:37AM, Eugen Leitl wrote: >>>> Forwarded message From Hugh Aguilar <[email protected]> >>>> Re: OPERATING SYSTEM ON A FPGA >>> >>> I don't understand what you want to get out of reposting this here? >>> ISTM that the thread on racket-users covers things pretty well... > >Myself, I have reposted original message to Info list because I thought it >could be interesting to someone else. It somehow went along my own topics. >I guess for the same reason it ended here. I wasn't surprised given the >group is about "future computing" which implies non-standard approach.
>I guess it is hard to go below some size with Scheme. Or some other well >developed Lisp. Especially that it is hard to go below some size with >compiler, too. The commercial Forth systems work on a tethered scheme. The compiler runs on a host computer, allowing it plenty of resources. On the target board you have a tiny communication program which allows the compiler to read or write target memory and to start execution from any address it wants. Then the compiler can build and download target code and run it on an incremental basis, preserving the interactivity of Forth. I have always wondered how far in that direction you could go with Scheme or another high-level dynamic language. In my (again, fairly uninformed) opinion it seems mainly a question of how much of the dynamic stuff can be analysed and compiled down to static code to reduce the runtime size/speed costs, and whether you can give the programmer the fine-grained control over memory usage that they might need for such limited systems. >Well, I don't know [Hugh] either. Comments made by you two forced me to dig >him out from search results. I guess the fair thing would be asking him a >question rather than disputing his personality like this. I will not ask >because I don't give a damn [...] Well, me neither, but I've read comp.lang.forth for as long as he has been posting there and haven't found that he has much to say that's worth digging through the attitude to get to. His Forth code is mostly pretty clunky and could be better designed, IMO. He tends to be overly concerned with micro-optimizations without looking at the big picture. And if anyone points out flaws in his work he generally jumps to personal attacks rather than discussing the technical issues. This is not to say that he never comes up with interesting stuff. It just tends to get lost in the noise. And you have to check it out yourself as he tends to make very strong claims, even when he clearly doesn't know what he's talking about. >> If anyone here is actually serious about the history of computing, they >> might consider writing a book about the culture of Forth. Seems to me >> there's some valuable material there which is gradually passing out of >> living memory. > >I would like to read such book. There are bits and pieces out there; Chuck Moore has written a couple of things and Jeff Fox has a bunch of essays. And the old Forth Dimensions newsletters are fun reading. Mostly it's a culture of YAGNI taken to extremes, on the assumption that it's cheap to extend the functionality when you find you actually need it. And a culture of distrusting academic work and complex compilers and having the programmer make as many decisions as possible. I've been interested in Forth for about 10 years; I came to computing via Basic and then x86 assembly language, and when I was 16 (1996) I started asking myself what was the simplest compiler I could build that would get me significantly more power than assembly language and came up with something remarkably similar to Forth (it was a pleasant surprise discovering the actual Forth language 5 years later). So I tend to think that most of the stuff is obvious if you're coming from that direction, and I haven't come up against any code or prose from the Forth folks that makes me feel differently. There *is* several decades of people working on it, so there are a bunch of interesting tricks. And of course YMMV. I could come up with a bunch of links if anyone is interested... --Josh _______________________________________________ fonc mailing list [email protected] http://vpri.org/mailman/listinfo/fonc
