Re: member returns list

[Barry Margolin <barmar@alum.mit.edu>]

In article <mailman.719.1441763081.19560.help-gnu-emacs@gnu.org>,
 Robert Thorpe <rt@robertthorpeconsulting.com> wrote:

> "Pascal J. Bourguignon" <pjb@informatimago.com> writes:
> 
> > "Pascal J. Bourguignon" <pjb@informatimago.com> writes:
> >
> >> Emanuel Berg <embe8573@student.uu.se> writes:
> >>
> >>> "Pascal J. Bourguignon" <pjb@informatimago.com>
> >>> writes:
> >>>
> >>>> Because each implementation worked on a different
> >>>> machine with a different OS (if an OS was available
> >>>> at all).
> >>>
> >>> Yeah, but there were many machines at the time of the
> >>> "crazy language" C as well, still, there aren't
> >>> a plethora of C dialects. (If you don't count all the
> >>> epigone languages that borrowed heavily the syntax
> >>> of C.)
> >>>
> >>> But C is famous for its portability (which also
> >>> proliferated Unix) - perhaps the exception that
> >>> confirms the rule, that Lisp is cooler than C?
> >>
> >> It's not exactly the same time period, and not the same kind of
> >> machines.
> >>
> >> Basically, C was running on small machines, that were all the same.
> >> After C the micro-processors appeared, and since they were so bad, they
> >> soon were optimized to run C code efficiently.
> 
> I don't really agree with Pascal's view.
> 
> Anyway, there were some other reasons why Lisp implementations differed
> between machines.  As Pascal said, the early Lisp implementations were
> on mainframes.  Later on people tried to port Lisp to minicomputers and
> microcomputers.  But, Lisp was already quite complex and it wasn't
> possible to fit all the features.  So, some of the features got
> excluded, and which were excluded varied.

This doesn't explain why there were such drastic differences between the 
mainframe Lisps.

Remember that in the 70's, when much of the Lisp evolution was 
happening, we didn't have the Internet (Arpanet was still in its early 
days, but there was no WWW yet). The folks at the Stanford, CMU, and MIT 
AI Laboratories couldn't easily collaborate on a daily basis like they 
can now. So each group developed their own Lisp dialects, based on the 
preferences of their developers.

It's not really much different from why we now have a profusion of 
languages for writing web server-side applications: Perl, PHP, Python, 
Ruby. Different people have different style preferences.

-- 
Barry Margolin, barmar@alum.mit.edu
Arlington, MA
*** PLEASE post questions in newsgroups, not directly to me ***