On Tue, 19 Apr 2022 20:00:53 +0200
Helmut Eller <eller....@gmail.com
> On Tue, Apr 19 2022, Spiros Bousbouras wrote:
> > When I look at the various "Issues" in CLHS , I see several Common Lisp
> > implementations being mentioned. I haven't counted but I estimate around 20.
> > Some of them are commercial. This suggests that a lot of Lisp code was being
> > written at the time the standard was being developed (1980s). The code might
> > not have been Common Lisp but was in Lisp languages close to Common Lisp. So
> > does anyone know what kind of code all those people were writing back then ?
> The Lisp machines were some of the early personal computers, a bit like
> the Smalltalk machines from Xerox PARC. They had relatively good
> graphic capabilities and were, for a time, quite fast. Lisp was the
> system language, on so everything from device drivers, file-systems,
> databases, gui frameworks etc. was written in Lisp (and microcode).
> Also keep in mind, Lisp machines were expense; in todays dollars
> probably 50k upwards.
So then , after the Lisp machines lost relevance , a lot of that code also
lost relevance and porting it to other hardware woudln't even be meaningful.
> It seems that the primary customers of Lisp machines were the big
> national laboratories in the USA. At that time, those were fully
> occupied with Cold War activities. Not sure what they used the Lisp
> machines for, maybe they played "WarGames" ;-).
Smiley noted but I wonder , is examining different scenarios (wargames
related or whatever) , i.e. going through a large number of different
combinations of moves , something Lisp would be good at ? This seems much
closer to the strengths of C or C++ or Fortran and I believe chess engines
get written in C or C++ with a bit of assembly thrown in. I can only imagine
Lisp being relevant if the evaluation of the final positions (after a
sequence of moves has been followed) is dynamic ; in other words if the
evaluation function changes in some complicated manner as the programme runs.
Or if the algorithm for choosing which moves to examine first and which later
changes in some complicated manner as the programme runs. I note that in
existing chess engines , moves which have been found more promising with
shorter lookahead , get examined first as the engine moves to longer
lookaheads. But such a simple heuristic would be no easier to achieve in Lisp
than in more static languages.
> But they certainly
> could afford the best and most expensive hardware. That's probably also
> the reason why DARPA funded the standardization of Lisp.
> On the commercial side, the most important application for Lisp were
> probably expert systems. At that time there was a big hype around
> expert systems and a lot of money was spent on them (and Lisp) before
> the bubble burst.
Were those expert systems delivering what the companies buying them hoped for
or were the companies too much influenced by hype and did not evaluate
correctly if they were getting their money's worth from Lisp code or Lisp
> > It's even more striking considering that computer hardware was much slower
> > back then so , for various tasks which a Lisp would be fast enough on today's
> > hardware , it might not have been fast enough back then.
> > Also , what happened to that code ? How much of it is still available today ?
> > Did it stop being useful and was eventually erased ? Was it eventually
> > rewritten in C++ or Java or whatever ?
> When Suns and other Unix workstations appeared, Lisp machines were no
> longer interesting as Suns were faster, cheaper and better. Some Lisp
> code was ported and some applications, e.g. Maxima or Axiom, are still
> around. On Unix, Lisp was never as relevant as C and after the AI
> Winter (collapse of expert system hype) Lisp never quite found a niche.
As another example , the "Issues" in CLHS sometimes mention Kyoto Common Lisp
which still exists as Embeddable Common Lisp.
Somebody was trying to tell me that CDs are better than vinyl because
they don't have any surface noise. I said, "Listen, mate, life has