comp.lang.scheme Google Group

Re: A question about lexical binding

an...@appsolutions.com (Anton van Straaten) — Tue, 10 Oct 2008 16:48:56 UT

The real meaning of lexical scope, compared to dynamic scope, is that
the meaning of a variable is given by the context in which the variable
was originally defined, and doesn't change depending on where a function
that uses that variable is called from.
The term commonly used here is "dynamic binding", rather than "deep

Re: A 'reconstructing' printer

arcf...@sacrideo.us (Aaron W. Hsu) — Tue, 10 Oct 2008 16:16:43 UT

I think that in general, this kind of thing is not possible. You may be
able to do special cases, but you can't guarantee to get the original
code back. After expansion, there is no way to tell how you expanded to
that code.
Aaron Hsu

Re: Was there a schism between R4RS and R5RS?

arcf...@sacrideo.us (Aaron W. Hsu) — Tue, 10 Oct 2008 16:11:31 UT

People inferred that Scheme was "not useful" for real programming
because the R5RS standard wasn't complete enough for real programming,
implying that a Scheme in practice -- meaning an implementation --
was useless for "real" programming.
Aaron Hsu

Re: A 'reconstructing' printer

xacc....@gmail.com (leppie) — Tue, 10 Oct 2008 12:40:14 UT

For those interested, here is the start of such a thing (for those
using psyntax):
(define (pp-expr so)
(define pe pp-expr)
(define (pe* sl) (map pe sl))
(syntax-case so (case-lambda if begin set! letrec letrec*)
[((case-lambda [(a ...) b b* ...]) p ...)
(with-syntax (((b ...) (pe* #'(b b* ...)))

Re: A question about lexical binding

p...@informatimago.com (Pascal J. Bourguignon) — Tue, 10 Oct 2008 12:30:12 UT

Same answer as in cll.

Re: A 'reconstructing' printer

xacc....@gmail.com (leppie) — Tue, 10 Oct 2008 11:18:00 UT

On Oct 14, 12:46 pm, Jens Axel Soegaard
Thanks Jens, that looks perfect :)

Re: A 'reconstructing' printer

findrealaddresswithgoo...@soegaard.net (Jens Axel Soegaard) — Tue, 10 Oct 2008 10:46:29 UT

Something like this?
[link]

A 'reconstructing' printer

xacc....@gmail.com (leppie) — Tue, 10 Oct 2008 10:08:38 UT

Hi
I am not sure if this is feasible or if someone has done something
similar, but I looking for something to help 'reconstruct' scheme code
that has already been through an expander.
Example
During expansion:
(let ((x #f)) x) => ((lambda (x) x) #f)
Now I am looking for something that can (but not need to) do the

A question about lexical binding

jurgen.defu...@pandora.be (chthon) — Tue, 10 Oct 2008 09:14:34 UT

For a couple of years (well, since I started learning Lisp and Scheme
in my spare time) already I am trying to fathom what the real meaning
of lexical scope is. I know how to use them, I program Perl at day,
and I know the extent of lexical variables, and I can use them to
build closures.
However, I am currently going over SICP, and I am building an

ANN: hop-1.9.2

manuel.serr...@inria.fr (Manuel Serrano) — Tue, 10 Oct 2008 06:20:10 UT

Hop is a programming language designed for the Web 2.0. It is a
higher-order language for programming interactive web applications
such as web agendas, web galleries, music players, etc. Hop can be
viewed as a replacement for traditional graphical toolkits. HOP is
implemented as a Web broker, i.e., a Web server that may act

Re: Was there a schism between R4RS and R5RS?

ven...@virgilio.it (Vend) — Tue, 10 Oct 2008 06:07:52 UT

On 14 Ott, 06:53, Abdulaziz Ghuloum <aghul...@cee.ess.indiana.edu>
wrote:
Indeed.

Re: Was there a schism between R4RS and R5RS?

aghul...@cee.ess.indiana.edu (Abdulaziz Ghuloum) — Tue, 10 Oct 2008 04:53:52 UT

Correct me if I'm wrong, but I don't think "people" talked about
"R5RS based Schemes" since everybody knows the usefulness of Chez,
Chicken, Gambit, MzScheme, etc., outside of research and teaching.
There might have been some talk about "R5RS the standard", which is,
for the most part, not that useful even for research and teaching

NYC LOCAL: Tuesday 14 October 2008, Two Separate Meetings: NYLUG Python, and Lisp NYC

secret...@lxny.org — Tue, 10 Oct 2008 04:15:33 UT

The NYLUG Python Workshop meets at 6:00 pm, Lisp NYC meets at
7:00 pm, on Tuesday 14 October 2008. The meetings are at two
different places.
For full information see the two official announcements below my
signature.
Jay Sulzberger <secret...@lxny.org>
Corresponding Secretary LXNY
LXNY is New York's Free Computing Organization.

Re: Was there a schism between R4RS and R5RS?

arcf...@sacrideo.us (Aaron W. Hsu) — Tue, 10 Oct 2008 02:03:57 UT

<rant>
Why do people continue to think that R5RS based Schemes were useless
or not very useful for real-world work outside of reasearch and
teaching? I used them commercially all the time, and they worked better
than many other infrastructures that people tried to sell me.
It is possible to make a very useful language that is also aesthetically

Re: Was there a schism between R4RS and R5RS?

ven...@virgilio.it (Vend) — Mon, 10 Oct 2008 22:22:17 UT

<rant>
If they want to design a crippled language just to fulfill some
abstract and entirely subjective aesthetic ideal, they can always make
something like Unlambda or Iota.
Scheme is supposed to be an useable and useful language, maybe not for
mass-producing websites, but at least for research and teaching, IMHO.